Astronomy 161 - Introduction To Solar System Astronomy - Autumn 2007

Saturn is attended by a system of 60 known moons and bright, beautiful rings. Today we will explore the moons of Saturn. Among the highlights are Saturn's lone giant moon, Titan, the 2nd largest moon in the Solar System and the only one with a heavy atmosphere. The atmosphere of Titan is mostly nitrogen with a little methane, but the temperature and pressure are such that methane plays the same role on Titan that water plays on the Earth: it can be either a solid, gas, or liquid. The Cassini and Huygens probes have recently shown that there is evidence of liquid methane flows and mudflats, and even liquid methane lakes as big as the Great Lakes or Caspian seas on Earth. The other moon of interest is Enceladus. The shiniest object in the Solar System, Enceladus has spectacular fountains - cryovolcanos - that spew water vapor from reservoirs created in its tidally-heated interior. This ice repaves much of the surface of Enceladus, giving it a young, shiny surface, and builds the E ring of Saturn. Recorde