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> There is also a stable polar orbit where the orbiter stays lined up between the Earth and the Moon. Since the surface is tidally locked you again get the lander back easily.

Wait, what keeps the polar orbit lined up with the Earth? If the orbit just stayed constant, it would deviate from being lined up from the Earth, right?

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It wouldn't be exactly a polar orbit, but slightly offset from one - like a sun-synchronous orbit around the earth

https://en.wikipedia.org/wiki/Sun-synchronous_orbit

Exactly. And since the orbit turns at the same speed as the Moon does, it works.

That is why in the article they offer a map of where the landing could have been and came up with https://hackadaycom.files.wordpress.com/2019/02/moonpossible...

You see the landings on the equator, and also the strip going over the pole.

But what makes the orbit turn? What is accelerating the satellite?

It uses the equatorial bulge to process the orbit.

https://space.stackexchange.com/questions/5312/why-would-sun...

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