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Dusk/dawn Sun-synchronous orbits are possible at Earth thanks to the fact that Earth is a bit flattened. Would it be possible with a similar orbit around the Moon?
The flattening of the Moon seems to be only about 1/30 of that of Earth. But an advantage might be that it would have the same distance to Earth as the Moon has, so the Earth should not disturb the orbit of such a spacecraft as much as if it were in an equatorial orbit. Would this kind of orbit be more or less demanding than other orbits?
An orbit over the Lunar terminator would provide constant sunlight, cover the entire Lunar surface since it is a polar orbit, and the dusk/dawn phenomena where the solar wind is shut down and turned on might be scientifically interesting to study.