The big dish antenna at Stanford University (visible from I-280) was, among many other things, used to monitor Soviet radar signals from Sary Shagan in Kazakhstan, that bounced off the moon some of the time.
which has this tidbit which explains why it works as well as it does when it works:
"Fortunately for us, the moon appears only slightly rough to radio waves; most of the reflected energy comes back from an area at the near point just a few miles in diameter. The bulk of the energy striking farther around on the side is reflected out into space and never returns to earth."
The wikipedia article:
https://en.wikipedia.org/wiki/Stanford_Dish
links to:
https://web.archive.org/web/20201108114110/https://www.cia.g...
which has this tidbit which explains why it works as well as it does when it works:
"Fortunately for us, the moon appears only slightly rough to radio waves; most of the reflected energy comes back from an area at the near point just a few miles in diameter. The bulk of the energy striking farther around on the side is reflected out into space and never returns to earth."