AS101 Lecture Notes - Lecture 19: Trailing Edge, Galilean Moons, Spectroscopy
Document Summary
Imagine two pieces of rock, each with a mass of 106 kg. One of them is at 109m from saturn (about the same distance as titan) and the other is 5000km = 5x106 m farther out, so at 1. 005x109 m. Elsewhere in the solar system, small objects (like the planet. Mercury) lose their internal heat quickly after they formed, and so geological activity (volcanism, etc. ) stopped long ago. But some of the satellites around jovian planets are still being heated by tidal stresses. Io is the closest to jupiter of the four large galilean satellites and shows active volcanoes. Cracks in surface ice suggest liquid underneath. Smooth surface without craters also suggests the surface is active, and frequently renewed by liquid from underneath. F=gm1m2r2f=gm1m2r2=6. 67 10 11(5. 68 1026)(106)(109)2=3. 79 104nf=gm1m2r2=6. 67 10 11(5. 68 1026)(106)(1. 005 109)2=3. 75 104n tidal heating could keep the interior warm enough to maintain liquid water under the surface. Europan ocean could be 10s of km deep.