1 Saturn Saturn ! Saturn is the second largest planet in the Solar Sys te m. ! The re are 30 known satellites of Saturn. ! The largest, Titan, has a thick nitrogen-rich atmosphere. ! Saturn has an extensive magnetosphere. Saturn emits 79% more energy than it receives from the Sun. What makes those colorful golden bands in Saturn’s uppe r atmosphe re? ---Ammonia ice crystals Saturn, Physical Attributes Saturn, Physical Attributes " Mean distance from Sun ≈ 9.5 AU " Radius ≈ 9.5 × R Earth " Mass ≈ 95 × M Earth " Density = Mass÷Volume ≈ 0.7 gm/cm 3 . " Lowest density of any planet. " Density of water = 1.0 gm/cm 3 . " Can float in water! " Low density implies composition similar to Jupiter’s; predominantly hydrogen and helium !Saturn’s primary atmospheric contents are: !Hydrogen (94%) !Helium (6%) !In addition, there are traces of ammonia, methane, ethane, phosphine, acetylene, methylacetylene, and propane. !Saturn has the second fastest measured winds in the Solar System. !Only Neptune has faster winds. Saturn, More Physical Attributes Saturn, More Physical Attributes Saturn, Interior Composition Saturn, Interior Composition " Overall structure similar to Jupiter’s " Mantle of liquid molecular hydrogen " Lower mantle of metallic hydrogen " Much more oblate than Jupiter. Equatorial diameter 10% larger at than polar " Rocky core is larger than Jupiter’s " 26% of Saturn’s mass is in its rocky core (24 times the Earth mass!) !Dark Cassini Division between A and B rings; Encke Division separates F and A !Icy particles from dust grain up to 10 m sizes !All rings within the Roche Limit !Shepherd satellites !Mimas produces Cassini Division Saturn, Rings Three main rings (A, B and C) from Earth; Many more found by spacecraft