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mfb- t1_j2xqps2 wrote

The Moon is about as reflective as asphalt, but various missions have left retroreflectors at their landing sites which are routinely targeted with lasers. They can measure the distance with a precision of a centimeter or so, depending on the experiment and targeted retroreflector.

Jupiter, Venus, Mars and Saturn and sometimes even larger asteroids need to be considered in these experiments, see e.g. this publication for a discussion. It's an extremely precise test of our understanding of gravity and the Solar System. Unfortunately it doesn't test MOND directly because a small acceleration from one specific object isn't enough (otherwise you could just say Earth is a billion objects providing a small acceleration each), you need a small acceleration overall. The Moon is not in such a place.

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