abundance of light elements - spectral analysis of stars & galaxies shows that there is a large...
TRANSCRIPT
THE BIG BANG THEORY
THE BIG BANG THEORY
THREE KEY DISCOVERIES
IN THE 20THCENTURY
LED TO THE
BIG BANG THEORY:
DISCOVERY #1
Abundance of Light Elements -Spectral Analysis of Stars & Galaxies shows that there is a large % of:
Hydrogen and Helium (99.9 %)
present in the universe today.
Abundance of Light Elements –Relative Abundance of Elements: Each number
on the Y scale represents a power of 10.
C lines up with the 7. That means there is 10X as much C as there is Si ( and 100X as much C as Ar!! )
There is a large % (99.9 %) of:Hydrogen and Helium
DISCOVERY #1
Abundance of Light Elements –Relative Abundance of Elements: Each number
on the Y scale represents a power of 10.
C lines up with the 7. That means there is 10X as much C as there is Si ( and 100X as much C as Ar!! )
This means the relative abundance of H is more than 10,000 X the relative abundance of Si!!!
DISCOVERY #1
DISCOVERY #1
Not surprisingly, these are the two smallest elements which we would expect to form from the protons and neutrons being thrown together during the Big Bang.
DISCOVERY #2
THE RED SHIFT
Edwin Hubble
Red Shift (Edwin Hubble - 1920s) – The light spectrum of distant
galaxies shows a distinct shift toward the red end of the spectrum.
As the galaxies become more distant, the Red Shift becomes more pronounced.
DISCOVERY #2
DOPPLER EFFECT AND RED SHIFT
Object coming towards you – blue shift (at very high speeds - 100 million mph)
Object moving away from you – red shift – Speeds have to be near the speed of light for the Doppler effect to be visible.
Astronomy and the Doppler Shift Astronomers can
measure the Doppler Shift of a moving object (galaxy):
If the galaxy is moving closer, waves will be compressed and will have a higher (“bluer”) frequency.
If galaxy is moving away, waves in the signal will be stretched, and will have a lower (“redder”) frequency.
RED SHIFT OF LIGHT FROM DISTANT GALAXIES
Very Distant Galaxy
Distant Galaxy
NearbyGalaxy
Nearby Star
Quantum Jump
Diagrams for
Hydrogen
Evidence for an expanding universe
The spectrum of Hydrogen gas is the unique fingerprint of that element.
Hydrogen lamp
H – Alpha line
Rest Wavelength – not moving at all
Evidence for an expanding universe
Orion Nebula
When we see a repeat of the pattern we saw in the lab, we know Hydrogen is present.
H – Alpha line
Nearby Wavelength
We see the same repeating pattern of lines in a galaxy, but displaced to the red .
Galaxy UGC 12915
Evidence for an expanding universe
H – Alpha line
Middle Distance Wavelength
The further away the galaxy is, the greater the shift to the red:
Galaxy UGC 12508
Evidence for an expanding universe
H – Alpha line
More Distant Wavelength
Galaxy KUG 1750
The greater the red shift, the faster the galaxy is receding away.
Evidence for an expanding universe
H – Alpha line
Even More Distant Wavelength
The red shift is caused by the expansion of space.
Galaxy KUG 1217
Evidence for an expanding universe
H – Alpha line
Great Distance Wavelength
The red shift is evidence for an expanding universe
Galaxy IRAS F09159
Evidence for an expanding universe
H – Alpha line
Greatest Distance Wavelength
Red Shift (Edwin Hubble - 1920s) –
All but a handful of nearby galaxies show a Red Shift .
Shows that virtually all galaxies are moving away from Earth.
DISCOVERY #2
Red Shift (Edwin Hubble - 1920s) –
Shows that virtually all galaxies are moving away from Earth.
The more distant a galaxy is, the faster it is moving, so all galaxies must be moving away from each other.
DISCOVERY #2
RED SHIFT of Light from Distant Galaxies
Very Distant Galaxy
Distant Galaxy
NearbyGalaxy
Nearby StarMoving away slowly
Moving away fast
faster
fastest
Red Shift (Edwin Hubble - 1920s) –
DISCOVERY #2
Conclusion:
The universe is expanding at
incredible speeds
(100 million mph- nearly at the
speed of light).
DISCOVERY #2
Conclusion:
The universe is expanding at
incredible speeds
(nearly at the speed of light).
Red Shift (Edwin Hubble - 1920s) –
Click here for
Movie:
DISCOVERY #3
is everywhere in space
It could only be caused by a huge thermonuclear-type detonation
Discovered byPenzias & Wilson – 1960s
COSMIC MICROWAVE BACKGROUND RADIATION
DISCOVERY #3
CMBR has cooled down from the
hotter cosmic rays and gamma
rays of the Big Bang to the lower
energy microwave radiation that
we see everywhere in space today.
COSMIC MICROWAVE BACKGROUND RADIATION
DISCOVERY #3
CMBR has stretched from the short,
high frequency cosmic rays and
gamma rays of the Big Bang to the
long, low frequency microwave
radiation that we see everywhere in
space today.
COSMIC MICROWAVE BACKGROUND RADIATION
Computer - generated maps of the universe using data from the COBE satellite
(COsmic Background Explorer)
show that
COSMIC MICROWAVE BACKGROUND RADIATION
is present everywhere in the universe.
(See next frame.)
COSMIC MICROWAVE BACKGROUND RADIATION
DISCOVERY #3
DISCOVERY #3
This image shows us the very edge of outer space – 13.7 billion light years away and comes from radiation that originated 13.7 billion years in the past! We are looking at lumps of radiation that filled the universe in its very early infancy.
COSMIC MICROWAVE BACKGROUND RADIATION
More recent images from the wmap satellite (2003 – 2010) show that the
COSMIC MICROWAVE BACKGROUND RADIATION
contains pockets of denser radiation that could have condensed into the early galaxies.
This lumpiness was predicted by the Big Bang Theory.
(See next frame.)
DISCOVERY #3COSMIC MICROWAVE BACKGROUND
RADIATION
WMAP SATELLITE IMAGE
COSMIC MICROWAVE BACKGROUND RADIATION
WMAP SATELLITE IMAGE
COSMIC MICROWAVE BACKGROUND RADIATION
led to the concept that the universe began expanding rapidly from a small hot point
13.7 billion years ago and is still expanding today…
A NEW WAY OF LOOKING AT THINGS...
DISCOVERIES 1, 2 AND 3:
A Stanmo ProductionThanks to NASA, JPL and the Einstein Forum for
the great pix.2012