The Solar System

Read the inner planet WS

Inner Planets WS

• 1. Mercury• 2. Venus• 3. Earth• 4. Mars• 5. all• 6.Earth• 7. Venus• 8. Mars• 9.Earth. Mars

• 10. Venus & Earth• 11. Mercury• 12. Venus• 13. Mars, Earth• 14. Mars• 15.The 4 inner planets

with rocky surfaces• 16.clockwise “backward”

rotation• 17. atmosphere traps in

heat warming the planet

Our solar system has 8 planets!

My Very Excellent Mother Just Served Us Nachos!

Vulcanoid Belt

• A belt of rocky objects between the sun and Mercury.

• We do not know with certainty that it exists because it is so close to the sun that glare would make small objects difficult to observe.

Planets

• 4 major criteria are required to be called a planet:

– a large body that shines by reflecting sunlight

– revolves in a stable orbit around the sun

– large enough that its own gravity pulls it into a round shape

– Must be dominant enough to clear the area around it

Terms to know!• AU: distance from the Earth to the sun

• Greenhouse Effect:– Atmosphere traps in heat like a blanket. – Thicker atmosphere = greater GH effect=like a thinker blanket– Stabilizes temperature

• Rotation:– Spinning– Determines a Day

• Revolution -orbit– Revolving around a star– Determines a year

• Satellite– Moons – Any object that orbits a planet!

Inner / Terrestrial Planets

• Which ones are the inner planets?

Inner Planets

• Which ones are the inner planets?– Mercury, Venus, Earth, Mars

• Inner planets are also called terrestrial planets. Why?

Inner Planets

• Which ones are the inner planets?– Mercury, Venus, Earth, Mars

• Inner planets are also called terrestrial planets. Why?– They are made mainly of rock and iron-nickel

compounds

Generally smaller in size

Only 2 of the inner planets are inferior.What are the 2 inferior planets?

• Inferior planets – – Most are between Sun and Earth – If closer to the sun, it shows phases like the moon!

Superior Planets

• Superior planets – – further from the Sun than Earth– always appear full (no phases like the moon)– What are the superior planets?

• Mars, Jupiter, Saturn , Uranus & Neptune

Inferior

PHASES

Superior – Always Full

The Inner Planets

Also called terrestrial planets

Mercury•Closest to the sun

•Many craters with little erosion

•Made of the dense metals iron & nickel

•Has almost no atmosphere,

•very hot during the day (430 C)

•very cold at night (-170 C)

•Little Greenhouse effect

•Has a Magnetic Field

•Hard to collect data from Mercury

•Mariner 10 (1970s) MESSANGER (now)

Mercury• Considered an extreme planet

– Smallest– Densest– oldest – largest daily variations in surface temperature – least explored.

0.39 AU

Venus - Earth’s Twin Planet

•similar in:

• size

•mass

•composition

•distance from the sun

• 0.72 AU

Why don’t we live on Venus?

Here is what is different:•no oceans, has volcanoes

•thick clouds that spin rapidly and trap heat on the surface GREENHOUSE EFFECT

•Mostly CO2

•Hottest surface of all! (460C)

•air pressure 90 x greater than Earth

What else is different?

•Retrograde Rotation:

•CLOCKWISE!

•Sun rises in the WEST!

•Day is 8 months long

•Revolution:

•Venus’ day is longer than it’s year

•7.5 earth months

Earth: Goldilocks!Just Right.

•71% water

•Only planet known to have life

•Nitrogen & Oxygen, CO2 and H2O

•Nitrogen is used in plants to make protein

•Magnetosphere

•Protects from solar flares

•Magnetic Field

•Produced by liquid outer core

1 AU

Mars•Small rocky and red

•iron oxide, or rust.

•Ice at the poles. Mostly Water & SOME Dry ice!

•Used to have liquid water, or ice below the surface.

•Largest Volcano in the Solar System

•Olympus Mons

•Largest Canyon

•Valles Marineris -From NY to LA

•Has 2 moons- Phobos and Deimos

•Rotation: almost the same as Earth

•Revolution:687 days in an Martian year

•Atmosphere: mostly of carbon dioxide.

•Strong Winds

•1% the pressure of Earth

•Thin atmosphere: 20C to -140C

1.5 AU

Mars

• There are currently several probes and satellites around Mars and rovers on Mars

• planned mission to send humans to Mars within the next 30 years. – Funding was cut

Asteroid belt

↓

Asteroid belt

• between Mars & Jupiter

• thousands of rock fragments that orbit around the sun

• Too small to be spherical or clear a path

• Largest asteroids have been reclassified; now called Dwarf planets– Ceres!

Read the Outer Planet WSanswers

1. Jupiter, Saturn, Uranus, Neptune

2. Jupiter, Saturn, Uranus, Neptune

3. Doesn’t clear its path (other objects in its orbit), not a planet, small and rocky

4. Large gravity

5. The sun! (too cold, not nuclear fusion)

6. Jupiter

7. Ice and rock

8. Uranus orbit was a bit off, so must have been influenced by an unseen planet. Predicted!

9. Does not clear its path

10.The 4 large outer planets. No solid surface, but a solid core.

Diagram order:

• Mercury

• Venus

• Earth

• Mars

• Jupiter

• Saturn

• Uranus

• Neptune

Outer planets

• Which planets are included in the outer planets?

Outer planets

• Which planets are included in the outer planets?– Jupiter, Saturn, Uranus, Neptune

Outer planetsJovian Gas Planets

• Which planets are included in the outer planets?– Jupiter, Saturn, Uranus,

Neptune

• Made up mostly of frozen hydrogen and helium

• Atmospheres can be made of thick layers of methane and ammonia

Jupiter• Atmosphere:

– A frozen & liquid “gas” planet • H and He are not gasses here

– Great Red Spot: • an ongoing storm “hurricane”• Larger than Earth

– Pressure is 30 million times greater

• Largest planet – 2x mass of all other planets together– Solid core of iron

• Rotation: Day = 9.9 hours

• Revolution: Year= ~12 Earth yrs

• Satellites: 63 moons– Europa might have life under the ice.

5.2 AU

Saturn•Another gas planet

•Size- 2nd largest

•smaller than Jupiter

•larger diameter because of rings

•Hundreds of Rings

•chunks of ice and rocks orbiting

•only planet with a density < water

•In a huge bathtub what would happen?

•Satellites- at least 61 moons!

•largest moon- Titan

•Larger than Mercury!

•atmosphere like early Earth's

9.5 AU

Saturn’s Rings

Hubble telescope picture of auroras occurring on Saturn

Outer planets

– What does this tell you about Saturn?

Uranus•Gas Planet

•Twice as far from the Sun as Saturn

•4x Bigger than earth.

•27 moons

•Rotation: day = 17 hours

•Revolution: year = 84 Earth days

•Has rings (dark colored)

•Appears blue

•methane gas in its atmosphere

•Axis tilted at a 90° angle, rotating from top to bottom, cosmic collision?

19.2 AU

Rotation Angles

• Look at Uranus!

• Rotates on its side!

• Looks like its rolling, not spinning like a top.

Centaurs

• Orbiting between Jupiter & Neptune

• 9 discovered so far

• Unstable orbits; astronomers believe that they are refugees from the Kuiper Belt

• Some may become comets

Neptune•Discovered by mathematical prediction!

•Atmosphere:

•blue -traces of methane gas

•Nitrogen ice

•Clouds and stormsWinds exceed 1000 Km/hrSpots – hurricanes

•13 moons

•Triton -Coldest in solar system= -200C

•Retrograde rotation like Venus!

•Must have been captured by Neptune’s gravity.

•Rotation: 16 hours

•Revolution: 164 years to orbit the sun!30 AU

Kuiper Belt↓

Kuiper Belt

• This disk-shaped

• icy debris

• 4.5 to 7.5 billion km from sun

• Pluto & most dwarf planets

• 800 objects discovered so far

Dwarf Planets• New classification occurred in 2006

Orbits around the sun (not a moon)pulled into a sphere

X Does NOT clear the neighborhood of its orbit

Dwarf Planets

• There are 5 dwarf planets known so far:– asteroid belt:

• Ceres

– Kuiper belt• Pluto• Eris• Makemake• Haumea

Oort Cloud

• spherical cloud surrounding our Solar System. • outer edge of our solar system• comets that streak by the Earth come from it• Sedna –

– farthest known object in our solar system– in the oort cloud– ¾ size of Pluto, – freezing cold (-400 F) – orbit =10,500 years to go around the Sun!!!!

Comets• ice and dust

• Least changed objects since the formation of the solar system

• 5 parts: nucleus, coma, hydrogen cloud, dust tail and ion tail

• Only visible when near the sun

• Halley’s comet – – visible every 76 years. – Next time we will see it is

2062.

Meteorites• Meteoroid- chunk of rock and ice debris in space

• Meteor- the light given off when it enters into Earth’s atmosphere (shooting star)

• Meteorite- impacts the surface (makes craters)

Meteorite - Arizona

Exoplanets

• What does the word exo mean?

Exoplanets

• What does the word exo mean?

• What is an exoplanet?

Exoplanets

• What does the word exo mean?

• What is an exoplanet?

– A planet outside of our solar system– There have been about 528 discovered so far– Some are “goldilocks” planets that may be a

lot like Earth.

Brown Dwarfs

• Failed stars: too big to be a planet, not big enough to have nuclear fusion