2. the sun.pdf
TRANSCRIPT
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 143
983124983144983141 983123983157983150
983118983157983154 983113983155983148983137983149983145
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 243
983113983118983124983122983119983108983125983107983124983113983119983118
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 343
Visible Image of the SunThe SunThe Sun
bullOur sole sourceof light and heat in
the solar s stem
bullA very common
star a glowing ball of
gas held together by its
own gravity and powered
by nuclear fusion at its
center
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 443
Pressure (from heat
caused by nuclearreactions) balances the
gravitational pull
toward the Sunrsquos center
Called ldquoHydrostatic
Equilibrium
spherical ball of gascalled the Sun
What would happen if
the nuclear reactions
(ldquoburningrdquo) stopped
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 543
983123983119983116983105983122 983120983122983119983120983109983122983124983113983109983123
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 643
Radius = 696000 km
(100 times Earth)
Mass = 2 x 1030 kg
(300000 times Earth)
Av Density = 1410 kgm3
Rotation Period =
Solar PropertiesSolar Properties
249 days (equator)298 days (poles)
Surface temp = 5780 K
Element
Hydrogen 709
Helium 274etc
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 743
Luminosity of the Sun
= LSUN
(Total light energy
emitted per second)
~ 4 x 1026 W100 billion one-
megaton nuclear bombs
every second
Solar constant
LSUN 4πR2
(energysecondarea
at the radius of
Earthrsquos orbit)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 843
The Solar InteriorldquoHelioseismologyrdquo
bullIn the 1960s it was
discovered that thesurface of the Sunvibrates like a bell
How do we know the interiorHow do we know the interior
structure of the Sunstructure of the Sun
bullInternal pressurewaves reflect off thephotosphere
bullAnalysis of thesurface patterns ofthese waves tell usabout the inside of the
Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 943
The Standard Solar Model
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 243
983113983118983124983122983119983108983125983107983124983113983119983118
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 343
Visible Image of the SunThe SunThe Sun
bullOur sole sourceof light and heat in
the solar s stem
bullA very common
star a glowing ball of
gas held together by its
own gravity and powered
by nuclear fusion at its
center
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 443
Pressure (from heat
caused by nuclearreactions) balances the
gravitational pull
toward the Sunrsquos center
Called ldquoHydrostatic
Equilibrium
spherical ball of gascalled the Sun
What would happen if
the nuclear reactions
(ldquoburningrdquo) stopped
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 543
983123983119983116983105983122 983120983122983119983120983109983122983124983113983109983123
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 643
Radius = 696000 km
(100 times Earth)
Mass = 2 x 1030 kg
(300000 times Earth)
Av Density = 1410 kgm3
Rotation Period =
Solar PropertiesSolar Properties
249 days (equator)298 days (poles)
Surface temp = 5780 K
Element
Hydrogen 709
Helium 274etc
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 743
Luminosity of the Sun
= LSUN
(Total light energy
emitted per second)
~ 4 x 1026 W100 billion one-
megaton nuclear bombs
every second
Solar constant
LSUN 4πR2
(energysecondarea
at the radius of
Earthrsquos orbit)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 843
The Solar InteriorldquoHelioseismologyrdquo
bullIn the 1960s it was
discovered that thesurface of the Sunvibrates like a bell
How do we know the interiorHow do we know the interior
structure of the Sunstructure of the Sun
bullInternal pressurewaves reflect off thephotosphere
bullAnalysis of thesurface patterns ofthese waves tell usabout the inside of the
Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 943
The Standard Solar Model
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 343
Visible Image of the SunThe SunThe Sun
bullOur sole sourceof light and heat in
the solar s stem
bullA very common
star a glowing ball of
gas held together by its
own gravity and powered
by nuclear fusion at its
center
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 443
Pressure (from heat
caused by nuclearreactions) balances the
gravitational pull
toward the Sunrsquos center
Called ldquoHydrostatic
Equilibrium
spherical ball of gascalled the Sun
What would happen if
the nuclear reactions
(ldquoburningrdquo) stopped
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 543
983123983119983116983105983122 983120983122983119983120983109983122983124983113983109983123
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 643
Radius = 696000 km
(100 times Earth)
Mass = 2 x 1030 kg
(300000 times Earth)
Av Density = 1410 kgm3
Rotation Period =
Solar PropertiesSolar Properties
249 days (equator)298 days (poles)
Surface temp = 5780 K
Element
Hydrogen 709
Helium 274etc
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 743
Luminosity of the Sun
= LSUN
(Total light energy
emitted per second)
~ 4 x 1026 W100 billion one-
megaton nuclear bombs
every second
Solar constant
LSUN 4πR2
(energysecondarea
at the radius of
Earthrsquos orbit)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 843
The Solar InteriorldquoHelioseismologyrdquo
bullIn the 1960s it was
discovered that thesurface of the Sunvibrates like a bell
How do we know the interiorHow do we know the interior
structure of the Sunstructure of the Sun
bullInternal pressurewaves reflect off thephotosphere
bullAnalysis of thesurface patterns ofthese waves tell usabout the inside of the
Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 943
The Standard Solar Model
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 443
Pressure (from heat
caused by nuclearreactions) balances the
gravitational pull
toward the Sunrsquos center
Called ldquoHydrostatic
Equilibrium
spherical ball of gascalled the Sun
What would happen if
the nuclear reactions
(ldquoburningrdquo) stopped
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 543
983123983119983116983105983122 983120983122983119983120983109983122983124983113983109983123
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 643
Radius = 696000 km
(100 times Earth)
Mass = 2 x 1030 kg
(300000 times Earth)
Av Density = 1410 kgm3
Rotation Period =
Solar PropertiesSolar Properties
249 days (equator)298 days (poles)
Surface temp = 5780 K
Element
Hydrogen 709
Helium 274etc
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 743
Luminosity of the Sun
= LSUN
(Total light energy
emitted per second)
~ 4 x 1026 W100 billion one-
megaton nuclear bombs
every second
Solar constant
LSUN 4πR2
(energysecondarea
at the radius of
Earthrsquos orbit)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 843
The Solar InteriorldquoHelioseismologyrdquo
bullIn the 1960s it was
discovered that thesurface of the Sunvibrates like a bell
How do we know the interiorHow do we know the interior
structure of the Sunstructure of the Sun
bullInternal pressurewaves reflect off thephotosphere
bullAnalysis of thesurface patterns ofthese waves tell usabout the inside of the
Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 943
The Standard Solar Model
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 543
983123983119983116983105983122 983120983122983119983120983109983122983124983113983109983123
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 643
Radius = 696000 km
(100 times Earth)
Mass = 2 x 1030 kg
(300000 times Earth)
Av Density = 1410 kgm3
Rotation Period =
Solar PropertiesSolar Properties
249 days (equator)298 days (poles)
Surface temp = 5780 K
Element
Hydrogen 709
Helium 274etc
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 743
Luminosity of the Sun
= LSUN
(Total light energy
emitted per second)
~ 4 x 1026 W100 billion one-
megaton nuclear bombs
every second
Solar constant
LSUN 4πR2
(energysecondarea
at the radius of
Earthrsquos orbit)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 843
The Solar InteriorldquoHelioseismologyrdquo
bullIn the 1960s it was
discovered that thesurface of the Sunvibrates like a bell
How do we know the interiorHow do we know the interior
structure of the Sunstructure of the Sun
bullInternal pressurewaves reflect off thephotosphere
bullAnalysis of thesurface patterns ofthese waves tell usabout the inside of the
Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 943
The Standard Solar Model
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 643
Radius = 696000 km
(100 times Earth)
Mass = 2 x 1030 kg
(300000 times Earth)
Av Density = 1410 kgm3
Rotation Period =
Solar PropertiesSolar Properties
249 days (equator)298 days (poles)
Surface temp = 5780 K
Element
Hydrogen 709
Helium 274etc
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 743
Luminosity of the Sun
= LSUN
(Total light energy
emitted per second)
~ 4 x 1026 W100 billion one-
megaton nuclear bombs
every second
Solar constant
LSUN 4πR2
(energysecondarea
at the radius of
Earthrsquos orbit)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 843
The Solar InteriorldquoHelioseismologyrdquo
bullIn the 1960s it was
discovered that thesurface of the Sunvibrates like a bell
How do we know the interiorHow do we know the interior
structure of the Sunstructure of the Sun
bullInternal pressurewaves reflect off thephotosphere
bullAnalysis of thesurface patterns ofthese waves tell usabout the inside of the
Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 943
The Standard Solar Model
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 743
Luminosity of the Sun
= LSUN
(Total light energy
emitted per second)
~ 4 x 1026 W100 billion one-
megaton nuclear bombs
every second
Solar constant
LSUN 4πR2
(energysecondarea
at the radius of
Earthrsquos orbit)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 843
The Solar InteriorldquoHelioseismologyrdquo
bullIn the 1960s it was
discovered that thesurface of the Sunvibrates like a bell
How do we know the interiorHow do we know the interior
structure of the Sunstructure of the Sun
bullInternal pressurewaves reflect off thephotosphere
bullAnalysis of thesurface patterns ofthese waves tell usabout the inside of the
Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 943
The Standard Solar Model
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 843
The Solar InteriorldquoHelioseismologyrdquo
bullIn the 1960s it was
discovered that thesurface of the Sunvibrates like a bell
How do we know the interiorHow do we know the interior
structure of the Sunstructure of the Sun
bullInternal pressurewaves reflect off thephotosphere
bullAnalysis of thesurface patterns ofthese waves tell usabout the inside of the
Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 943
The Standard Solar Model
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 943
The Standard Solar Model
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1043
Energy Transport within the Sun
bull Extremely hot core - ionized gas
bull Temperature falls further from core - more and more non-ionized atoms
capture the photons - gas becomes opaque to light in the convection zone
bull The low density in the photosphere makes it transparent to light - radiation
takes over again
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1143
Convection
Convection takes over when
the gas is too opaque for
radiative energy transport
Hot gas is less dense and
rises (or ldquofloatsrdquo like a hot air
balloon or a beach ball in a
pool)
Cool gas is more dense and
sinks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1243
Solar Granulation
Evidence for Convection
Solar Granules are the tops of convection cells
Bright regions are where hot material is upwelling(1000 km across)
Dark regions are where cooler material is sinking
Material risessinks ~1 kmsec (2200 mph Doppler)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1343
983124983112983109 983123983125983118 983105983124983117983119983123983120983112983109983122983109
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1443
The solar spectrum has
thousands of absorption
lines
More than 67 different
elements are present
The Solar Atmosphere
Hydrogen is the mostabundant element followed
by Helium (1st discovered
in the Sun)
Spectral lines only tell us about the part of the Sun that forms
them (photosphere and chromosphere) but these elements are
also thought to be representative of the entire Sun
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1543
Main Regions of the Sun
Visible
surface
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1643
983124983144983141 983120983144983151983156983151983155983152983144983141983154983141
bull 983124983144983141 983158983145983155983145983138983148983141 983155983157983154983142983137983139983141 983151983142 983156983144983141 983155983157983150
bull 983113983156 983145983155 983150983151983156 983155983151983148983145983140 983156983144983145983150 983148983137983161983141983154 983151983142 983143983137983155 983148983141983155983155 983156983144983137983150 98309300
983147983149 983140983141983141983152
bull 983141 983152983151983156 983151983155983152 983141983154983141 983155 983141983155983155 983156 983137983150 983137983155 983141983150983155983141983137983155 983156983144983141 983137983145983154 983145983150 983156983144983141 983141983137983154983156983144
bull 983106983141983148983151983159 983152983144983151983156983151983155983152983144983141983154983141 983156983144983141 983143983137983155 983145983155 983140983141983150983155983141983154 983137983150983140
983144983151983156983156983141983154
bull 983124983144983141 983143983154983137983150983157983148983137983156983145983151983150 983145983155 983137983152983152983141983137983154 983145983150 983156983144983141 983152983144983151983156983151983155983152983144983141983154983141
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1743
GranulesConvection from inside the sun causes the
photosphere to be subdivided into 1000-
2000km cells
Energy rises to the surface as gas wells up in the cores of
the granules and cool gas sinks around their edges
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1843
Chromosphere
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 1943
Chromosphere (seen during full Solar eclipse)
Chromosphere emits very little light because it is of low density
Reddish hue due to 3rarr2 (6563 nm) line emission from Hydrogen
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2043
bull 983124983144983141 983139983144983154983151983149983151983155983152983144983141983154983141991257983155 983140983141983150983155983145983156983161 983154983137983150983143983141983155 983142983154983151983149
10000983085100 983138983145983148983148983145983151983150 983156983145983149983141983155 983148983141983155983155 983156983144983137983150 983156983144983141 983137983145983154 983151983150983156983144983141 983141983137983154983156983144
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2143
Chromospheric Spicules
warm jets of matter
shooting out at ~100 kms
Spicules are thought to theresult of magnetic
disturbances
Hα light
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2243
Transition Zone and Corona
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2343
Transition Zone
amp Corona
We see emission
lines from highly
Very low density
T ~ 106 K
Why does the Temperature rise further from the hot light source
ionized elements(Fe+5 ndash Fe+13) which
indicates that the
temperature here is
very HOT
rarr magnetic ldquoactivityrdquo -spicules and other more energetic
phenomena (more about this laterhellip)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2443
Corona (seen during full Solar eclipse)
Hot coronal gas
escapes the Sun
rarr Solar wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2543
Solar Wind
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2643
Solar Wind
Coronal gas has enough heat (kinetic) energy to escape theSunrsquos gravity
The Sun is evaporating via this ldquowindrdquo
Solar wind travels at ~500 kms reaching Earth in ~3 days
The Sun loses about 1 million tons of matter each second
However over the Sunrsquos lifetime it has lost only ~01 of
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2743
Hot coronal gas (~1000000 K) emits mostly in X-rays
Coronal holes
are sources of
the solar wind
(lower density
regions)
Coronal holes
are related to the
Sunrsquos magneticfield
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2843
The Active Sun
UV light
Most of theSolar luminosity is continuous photosphere emission
But there is an irregular component
(contributing little to the Sunrsquos total luminosity)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 2943
983123983125983118983123983120983119983124
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3043
Sunspots
Granulation around sunspot
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3143
SunspotsSunspotsbull Typically about 10000 km
across
bull At any time the sun may
have hundreds or none
bull
are cooler than photosphericgas (4500K in darkest parts)
bull Each spot can last from a few days to a few months
bull Galileo observed these spots and realized the sun is rotatingdifferentially (faster at the poles slower at the equator)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3243
Sunspots amp
Magnetic Fields
bullThe magnetic field in a sunspot
is 1000x greater than the
surrounding area
bullSunspots are almost always in
pairs at the same latitude with
each member having opposite
polarity
bullAll sunspots in the same
hemisphere have the same
magnetic configuration
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3343
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3443
The Sunrsquos differential rotation distorts the magnetic field lines
The twisted and tangled field lines occasionally get kinked causing the field
strength to increase
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3543
Sunspot Cycle
Solar maximum is
reached every ~11 years
Solar Cycle is 22 years long ndash direction of magnetic field
polarity flips every 11 years (back to original orientation every 22 years)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3643
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3743
Charged particles (mostly
protons and electrons) are
accelerated along magnetic field
ldquolinesrdquo above sunspots
This type of activity not light
Heating of the Corona
Ch d ti l f ll ti fi ld b t t
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3843
Charged particles follow magnetic fields between sunspots
Solar Prominences
Sunspots are cool
but the gas abovethem is hot
S l P i
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 3943
Earth
Solar ProminenceTypical size is 100000 km
May persist for days or weeks
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4043
Very large solar prominence (12 million km across base
ie 39 Earth diameters) taken from Skylab in UV light
S l Fl
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4143
Solar Flares ndash much more violent magnetic instabilities
5 hours
Particles in the flare are so energetic the magnetic field cannot bring themback to the Sun ndash they escape Sunrsquos gravity
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4243
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)
7212019 2 The Sunpdf
httpslidepdfcomreaderfull2-the-sunpdf 4343
983124983137983155983147 983090bull 983117983137983147983141 983151983150983141 983152983137983152983141983154 (983091983085983093 983152983137983143983141983155) 983156983144983137983156 983140983145983155983139983157983155983155
983137983138983151983157983156983098 983118983157983139983148983141983137983154 983142983157983155983145983151983150 983145983150 983156983144983141 983155983157983150 983137983150983140 983145983156983155983145983149983152983148983145983139983137983156983145983151983150
bull 983119983150983141 983143983154983151983157983152 (983139983144983151983155983141983150 983154983137983150983140983151983149983148983161) 983159983145983148983148 983152983154983141983155983141983150983156 983145983156
983159983145983156983144983145983150 9830900 983149983145983150983157983156983141983155 (1983093 983149983145983150983157983156983141983155 983142983151983154
983152983154983141983155983141983150983156983137983156983145983151983150 + 983093 983149983145983150983157983156983141983155 983121amp983105)