Well that is fascinating. I am reading The Sparrow by Mary Doria Russell. Part of the plot is that a radio astronomer at Arecibo discovers intermittent Alien r

Well that is fascinating. I am reading The Sparrow by Mary Doria Russell. Part of the plot is that a radio astronomer at Arecibo discovers intermittent Alien radio signals originating from the Alpha Centari System. The protagonists can't figure out why the Alpha Centari's are transmitting such strong radio signals and why they are intermittent. It turns out that their planet doesn't have an ionosphere to reflect broadcast radio waves, so the inhabitants instead bounce radio off the moon to broadcast it back to the surface. Arecibo only picked up the radio signals when they bounced off the moon at the right angle. The origin of radio telescopes in the 60s must be the kernel for that bit of plot.