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My late father in law was an optical man, researching into his 80's, and he had a party trick. He would take folk out in the middle of the night, carrying a powerful (visible light! ) torch, so far left switched off.

Then he'd get his audience to join him lying on their backs on a bit of grass looking up at the stars. Picking out a weak star feature, getting both parties to focus on it, he'd then switch on the torch and point it at the weak star. Sure enough, the weak star would brighten. No explanation offered ..... but it works.

Michael Bradley