You get, on average, one photon back per laser shot. So you need a single-photon detector, a lock-in amplifier, a pulsed laser (50 or 60 Hz will give you a nice

You get, on average, one photon back per laser shot. So you need a single-photon detector, a lock-in amplifier, a pulsed laser (50 or 60 Hz will give you a nice tone to listen for) and a reasonable size telescope. It's a really small signal. But it could be done by a high school physics class if they were good at scrounging apparatus. Edited to add: the laser power needed is a few watts average, and the telescope aperture needed is probably 30cm at least, with a tracking mount. Without a picosecond laser, you're not going to be able to measure the distance accurately, but you could probably see a detectable line on a scatterplot or waterfall display.