Tides and Orbital Evolution

Normal Satellite Orbital Evolution

Satellites normally develop circular orbits with synchronous rotation as a result of tidal forces. A circular/synchronous orbit creates a static tidal bulge, which in turn, renders the satellite geologically inactive.

Geological Activity

Geological activity is caused by tidal friction. Without rotational tides or radial tides to produce tidal friction, a satellite/planet becomes geologically inactive.

Normal Satellite Orbital Evolution

Satellites normally develop circular orbits with synchronous rotation as a result of tidal forces. A circular/synchronous orbit creates a static tidal bulge, which in turn, renders the satellite geologically inactive.

Early Assumptions

Satellites of low mass move into circular/synchronous orbits quickly. It was once thought that the Galilean Moons were in such an orbit. However, infrared observations of Io hinted at geological activity. Speculations were fueled by theories of orbital resonance.

Forced/Free Eccentricity

Free Forced

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