Solar System Overview

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Solar System Overview
How is the Solar System Organized? How did
the Solar System form? When? How do we know?
http//www.solarviews.com/cap/misc/ss.htm
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• Some data to explain
• 1. Planets isolated
• 2. Orbits circular / in same plane
• 3. Planets (and moons) travel along orbits in
  same direction. same direction as Sun rotates
  (counter-clockwise viewed from above)

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Some more data to explain 4. Most planets rotate
in this same direction
http//www.solarviews.com/eng/solarsys.htm
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• And some more data to explain
• 5. Solar System highly differentiated

Terrestrial Planets (rocky, dense with density
4-5 g/cm3) Jovian Planets (light, gassy,
H, He, density 0.7-2)
http//www.solarviews.com/eng/solarsys.htm
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How Did We Get A Solar System?
Solar Nebula Theory
http//www.olemiss.edu/courses/astr103/Topics/Orig
in-N.html
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How Did We Get a Solar System?
Huge cloud of cold, thinly dispersed interstellar
gas and dust threaded with magnetic fields that
resist collapse
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How Did We Get a Solar System?
Concentrations of dust and gas in the cloud
material starts to collect (gravity gt magnetic
forces)
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How Did We Get a Solar System?
Gravity concentrates most cloud material near
center Grows! Heat and pressure
increase Collapses central proto-sun rotates
faster (probably got initial rotation from the
cloud)
LPI
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How Did We Get a Solar System?

• Spinning sphere? Material in orbit around core
  gets added to mid-disk
• Rotating, flattening, contracting disk - solar
  nebula!
• Equatorial Plane
• Orbit Direction

http//rainbow.ldeo.columbia.edu/courses/v1001/7.h
tml
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How Did We Get a Solar System?

• After 10 million years, material in center of
  nebula hot enough to fuse H
• ...here comes the sun

http//rainbow.ldeo.columbia.edu/courses/v1001/7.h
tml
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How Did We Get a Solar System?

• Condensation (gas forms solid dust particles)
• Metallic elements (Mg, Si, Fe) condense into
  solids at high temps. Combined with O to make
  tiny grains
• Lower temp (H, He, CH4, H2O, N2, ice) - outer
  edges
• Planetary Compositions

http//rainbow.ldeo.columbia.edu/courses/v1001/7.h
tml
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How Did We Get a Solar System?

• Inner Planets
• Hot Silicate minerals, metals, no light
  elements, ice
• Chondrules silicate mineral drops - flash
  heating as the solid matter condensed
  (meteorites)
• Begin to stick together with dust ? clumps

LPI
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How Did We Get a Solar System?

• Accretion - particles collide and stick together
  or break apart gravity not involved if small
  pieces
• Form planetesimals, up to a few km across

LPI
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How Did We Get a Solar System?

• Gravitational accretion planetesimals attract
  stuff
• Large protoplanets dominate, grow rapidly, clean
  up area ( takes 10 to 25 My)

LPI
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How Did We Get a Solar System?

• Outer Solar System
• Cold ices, gases 10x more particles than
  inner
• May have formed icy center, then captured lighter
  gases (Jupiter and Saturn first? Took H and He?)

LPI
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How Did We Get a Solar System?

• Early burst of solar wind - sweeps debris out of
  system
• Gravitational accretion of gas for protoplanets
  in the coolest nebular parts

LPI
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How Did We Get a Solar System?

• The Asteroid Belt
• ? Should have been a planet instead of a debris
  belt? Jupiter kept it from forming

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How Did We Get a Solar System?

• Beyond the Gas Giants - Pluto, Charon and the
  Kuiper Belt objects
• Chunks of ice and rock material
• Little debris available to make a planet

http//www.solarviews.com/eng/pluto.htm