Satellites of Satellites
No "moons of moons" (natural satellites that orbit the natural satellite of another body) are known. In most cases, the tidal effects of the primary would make such a system unstable.
However, calculations performed after the recent detection of a possible ring system around Saturn's natural satellite Rhea indicate that satellites orbiting Rhea would have stable orbits. Furthermore, the suspected rings are thought to be narrow, a phenomenon normally associated with shepherd moons. However, targeted images taken by the Cassini spacecraft failed to detect any rings associated with Rhea.
It has also been proposed that Saturn's satellite Iapetus possessed a subsatellite in the past; this is one of several hypotheses that have been put forward to account for its equatorial ridge.
Read more about this topic: Natural Satellite
Famous quotes containing the word satellites:
“To the Japanese, Portugal and Russia are neutral enemies, England and America are belligerent enemies, and Germany and her satellites are friendly enemies. They draw very fine distinctions.”
—Jerome Cady, U.S. screenwriter, and Lewis Milestone. Peter Voroshevski (Howard Clinton?)