There is a retroreflector on the moon, placed there, I believe, by astronauts in the 1970s. I think there is at least one station (in France?) that continuously beams a laser at it to measure the distance to the moon. I assume it measures the distance by measuring the amount of time it takes the laser light to travel to the moon and back again.
Is it possible for amateur to use the reflector? How powerful a laser would be needed, and how sensitive a detector? What would be the basic setup?