Can impact craters on the moon act like giant radio telescopes? Could large craters on the moon be used as reflective lenses for radio signals?

Acting like a large radio telescope reflecting radio waves to a satellite positioned over the crater.
Interesting idea. I think the answer is both yes and no -- yes with a manufactured dish but no in the crater's raw state.

The Arecibo telescope sits in a natural crater, but adds a dish which has a couple of important things required by a radio dish:


a radio-reflective surface
a specific curvature, classically parabolic, but also shaped
low surface roughness typically in the order of mm to µm for radio frequencies we're interested in. See http://en.wikipedia.org/wiki/Ruze%27s_Equation
a receiver close to the reflective surface (focal length), a satellite would probably be beyond the focal point
probably some some other things, but that's probably enough.


Edit: Added #4