Sinus Medii

Surveyor 6 landed in Sinus Medii in November 1967 and, twelve days later, fired its engines for 2.5 seconds and hopped 2.4 metres sideways - the first liftoff from the surface of another world. The manoeuvre tested restart of a lander engine and gave a stereo pair of the disturbed ground beside it.

The site is the sub-Earth point, where the Earth stands overhead permanently, moving only through the small circle that libration allows. That is convenient for communication and useless for observing: the Sun still sets, and the night is still fourteen days long.