Yes, it is similar to tidal locking. (as in Earth's Moon around Earth. It is thought (the last time I checked, which was about 10 years ago) to be a consequence of an assymmetric mantle.

Resonances (of time, distance, or orbital spacings)are quite common -- if something is out of resonance, gravity will gradually "pull" it into a resonance and, once it is there, there is nothing to shift it (any slight divergence will result in it being "pulled" back).



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Stephen