It was originally a joke, with Saturn as an spacecraft designed to be in disguise as a Planet, beaming a deathray at the Earth. If you've seen the movie "2001, a Space Odyssey", it's like the Monolith which is stationed on the Moon, causing us to become violent, ambitious, and technological.
Then, I happened to find out that, unlike Saturn, the Moon and other Planets don't emit detectable energy of their own, and just reflect solar radiation. (Please don't tell those
that I accidentally figured it out!)