1. Chapter 14 Section 4

2. GAS GIANTS Jupiter, Saturn, Uranus, and Neptune Don’t’ have solid surfaces Atmospheres composed of mainly hydrogen and helium Thick atmospheres Extremely cold due to being far from the sun Surrounded by a set of rings Many moons

3. JUPITER Largest and most massive planet Great red spot – storm like a hurricane that is larger than Earth Jupiter has 63+ moons 12 Earth years = 1 year on Jupiter 10 Earth hours = 1 Jupiter day

4. ~ -234 degrees F or -145 degrees C Galileo discovered Jupiters four largest moons Io Europa Ganymede Callisto https://www.brainpop.com /science/space/jupiter/

5. SATURN Second largest planet in our solar system Average density is less than water Saturn has rings made of chunks of ice and rock, each traveling in its own orbit 47+ moons 29 Earth years = 1 Saturn year 10.5 Earth hours = 1 Saturn day

6. ~-270 degrees F or -168 degrees C Largest moon is Titan discovered in 1665 as light not confirmed until Voyager probes flew by Titan’s atmosphere is so thick little light can pass through it https://www.brainpop.com/science/space/saturn/

7. URANUS Discovered in 1781 by William Herschel in England Made him famous Started a search for more solar system studies Twice as far from the sun as Saturn so it is very cold Blue/green in color due to traces of methane in the atmosphere Surrounded by thin dark rings 17 Earth hours = 1 Uranus day 84 Earth years = 1 Uranus year

8. Voyager 2 went to Uranus and sent back pictures of the planet (only spacecraft that has visited) It is tilted on its axis at an angle of ~90 degrees Retrograde motion (spins east to west) Scientists believe billions of years ago it was hit by an object and knocked onto its side 27+ moons that have craters and lava flows https://www.br ainpop.com/sci ence/space/ura nus/

9. NEPTUNE A cold blue planet Atmosphere contains visible clouds Discovered due to a mathematical prediction Uranus was not following its predicted orbit Gravity of another planet was affecting it

10. 1989 Voyager 2 flew by Neptune and saw a Great Dark Spot about the size of Earth Probably a giant storm Disappeared by the time we went back 5 years later 13+ moons Largest moon is Triton, has nitrogen ice in its south pole 164 Earth years = 1 Neptune year 16 Earth hours = 1 Neptune day Voyager 2 is the only spacecraft to have visited https://www.brainpop.com/science/space/neptune/

11. PLUTO Not a planet anymore!!!! https://www.youtube.com/watch?v=Z_2gbGXzFbs https://www.brainpop.com/science/space/pluto/ New horizons will arrive in July 2015 9.5 years to get there, launched in Jan 2006