Inner and Outer Planets

1
Inner and Outer Planets

• Chapter 2-3 and 2-4

2
Inner Planets

• Small and have rocky surfaces
• Four
• Also called terrestrial planets
• Mercury, Venus, Earth, Mars

3
Mercury

• Closest to the sun
• No moons
• Hard to view b/c so close to sun
• Flat plains, many craters (Mariner 10-single
  probe)
• Atmosphere really thin, weak gravity (b/c so
  small), VERY HOT (430C)
• Because no atmosphere, heat escapes at night
  (-170C)

4
Venus

• In west after sunset (can see it)
• evening star even though its not a star
• Similar in size to earth
• 7.5 earth months to revolve around the sun
• 8 months to rotate (so year is less than day)
• Retrograde rotation rotates from east to west

5
Venus Cont

• Atmosphere very thick, every day is cloudyno
  sunny days
• If you stood on Venus, you would be crushed by
  the atmosphere
• Becomes hotter and hotter because carbon dioxide
  traps heat Greenhouse Effect
• Magellan had radar that could go through
  atmosphere

6
Earth

• Atmosphere of mostly oxygen
• 70 covered with water (like no other planet)
• 3 main layers crust, mantle, core

7
Mars

• red planet
• Atmosphere is mostly carbon dioxide
• Has some water present in the form of ice
• Has seasons axis is tilted, wind causes dust
  storms
• Lost of spacecrafts have been there!
• 2 very small moons

8
The Outer Planets

• Jupiter
• Saturn
• Uranus
• Neptune
• Pluto?????

9
Gas Giants

• First 4 outer planets Jupiter, Saturn, Uranus,
  Neptune
• Gas Giant very large
• Pluto (not included) small and rocky like
  terrestrial planets

10
Jupiter

• Largest Planet
• Atmosphere thick atmosphere made up mainly of
  hydrogen and helium
• Contains colorful bands and swirls of thick
  clouds (Great Red Spot similar to an ongoing
  hurricane on earth, never ending storm)
• Moons Io, Europa, Ganymede, and Callisto

11
Jupiters Moons

• Io covered with volcanoes, erupting all the
  time, so Ios surface changes (larger than
  Earths own moon)
• Ganymede largest of Jupiters moons, twice the
  mass of earths moon.surface is icy and partly
  covered with craters (partly giant grooves of
  ice)
• Callisto icy surface, covered with craters

12
Saturn

• Second-largest planet
• Thick atmosphere
• Clouds and storms
• Planet is less dense than water
• Rings made of chunks of ice and rock, traveling
  around its own orbit around Saturn
• Hundreds of rings
• Titan largest moon (very thick atmosphere)
• Other moons Tethys, Lapetus, Dione, and Rhea

13
Uranus

• Much smaller than Jupiter and Saturn
• Much colder (twice as far from sun as Saturn)
• 17 hours to rotate (day)
• 90 degree tilt on axis, so rotates from top to
  bottom instead of side to side
• Moons 5 large moons (icy surfaces)
• Cratered surfaces
• Lava flows

14
Neptune

• Atmosphere has visible clouds
• Great Dark Spot giant storm
• 5 years later, dark spot was gone
• Smaller spots seem to come and go
• Moons 8 moons revolving around Neptune
• Largest moon Triton (cap of ice on southern
  pole.dark material erupts from underneath)

15
Pluto and Charon

• Solid surfaces
• Much less mass than earth
• Double planet instead of planet and moon
• 248 earth years is one year on Pluto (because so
  far away from sun)
• So small, is it a planet?????