General Science Notes 30.3 – The Outer Planets • General info on the four outer planets… o Formed far from the sun, so the temperature was much cooler  Water only existed as ice  Heavy elements were scarce, gases abundant • Such gases as: hydrogen, helium, methane and ammonia o Grew very fast and very large  Not extremely dense. Great in mass but even greater in volume… o The order of the four…  Jupiter: the largest planet, red/white/brown, has “moon-planets”  Saturn: distinct ring system, the “lightest,” or least dense planet  Uranus: blue/green color, “tilted” to its orbit plane, oceans of H2O  Neptune: blue w/ the fastest winds in the solar system • Other objects in our solar system… o Dwarf Planets  Nearly round in shape  Orbit the sun (very far away)  Very small in size/diameter  Have not cleared “debris” in their orbit pathway  Examples: Pluto, Eris, Ceres o Comets  Dust, rock, frozen water, ammonia and methane  Form far away from the sun in the Kuiper Belt and Oort Cloud  Orbit sharply around the sun o Asteroids  Rocky objects formed b/t Mars and Jupiter (The Asteroid Belt) o Meteoroids (Meteors)  Smaller asteroids (sand to boulder size)  Only observable once they enter the Earth’s atmosphere • Typically “burn up” upon entry (SHOOTING STARS)  Some make it through, causing great impacts