captured rotation

Definition

Astronomy

  • Dynamic condition whereby a body such as a satellite orbits another and rotates on its own axis in the same period, like the Moon in its orbit around the Earth. This means that (apart from areas visible because the Moon’s orbit is not exactly circular) we only see one side of the Moon from the Earth. Space probes have shown that captured rotation is common in the solar system, and there are also less simple cases like that of Mercury, which turns on its axis three times in two Mercurian years.
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