Outer Planets Jupiter Saturn Uranus Neptune

Composed mainly of hydrogen and helium Gas Giants Composed mainly of hydrogen and helium Very large- strong gravity Thick atmospheres

Jupiter Characteristics Largest Planet 4 moons IO Europa Ganymede Callisto More moons all larger than Earth’s moon Has rings-not visible from Earth

Jupiter Atmosphere Thick made mostly of Hydrogen Helium Liquid form because of pressure Great Red Spot Storm larger than Earth Hurricane-like Temperature -459

Voyager 1 &2 flybys Voyager 1 discovered rings Jupiter Missions Misssions Pioneer 10 1972 flyby Pioneer 11 1973-1995 flybys Voyager 1 &2 flybys Voyager 1 discovered rings 1995 Probe Galileo

Saturn Characteristics Moon Titan – main one – 4 others 2nd largest planet Rings – made of ice and rock chunks

Saturn Atmosphere Very thick -240 Clouds and storms Temperature Made of; Hydrogen & helium Temperature -240

Cassini/Huygens 1997 Saturn Missions Pioneer 11 flyby 1979 1980 flyby Voyager 1 Voyager 2 1981 Cassini/Huygens 1997

Cassini/Huygens Orbiter Probe

Uranus Cold Looks blue-green because of methane Thin flat rings (ice boulders and dust)

Uranus Earth Uranus Axis is tilted at 90° from vertical Rotates top to bottom NOT side to side Uranus Earth Theory is : it was hit by object and knocked it on its side Many moons

Uranus Atmosphere 83 % hydrogen 17 % helium Clouds Temperature -360°

Uranus Missions Voyager 2 – 1986 flyby

Neptune Characteristics *Cold, blue *Theory: it’s slowly shrinking interior heats up producing clouds and storms. *13 moons Tritan – largest *Faint rings

Neptune Atmosphere *Clouds *Methane gas absorbs light & gives it blue color *Great Dark Spot Plume cloud

Neptune Mission Voyager 2 Flyby 1989