AS101 Lecture Notes - Lecture 8: Galilean Moons, Active Object, Solar Wind
Document Summary
The three inner galilean moons orbit jupiter in a 1:2:4 resonance as shown here: An interesting feature of the galilean moon orbits is that the rotational periods of. Io, europa, and ganymede are in a 1:2:4 resonance; a feature which gives io an elliptical orbit thereby creating significant tidal forces on its interior resulting in continuous tidal heating and an active planet. Another interesting feature of io is the plasma torus that has formed in its orbit; the ions and electrons in this "electrical circuit" come from solar wind particles trapped in jupiter"s magnetosphere and from volcanically- ejected charged particles. Consequently, a 400,000 volt potential exists across io"s surface resulting in a 5 million amp current flowing through it and around the torus generating its own magnetic field along with that produced by io"s molten interior. One way to find out is to view them at sunset. Tall structures facing the sun are then better-lit and cast long shadows.
