What Would a Rainbow Be Like on Tatooine?

We get rainbows when sunlight is refracted through water in the atmosphere. It's an optical phenomena, so it all depends on where you are standing. The rainbow moves when you do, and that's why you can never reach the end of it. What would be different on a planet that orbits a binary star system, like Tatooine? Well, first off, Tatooine is a desert planet, so we can imagine that rain and water droplets in the air would be quite rare. For another thing, Tatooine is fictional. But we can speculate, what is what they do in the What If? series by Randall Munroe and Henry Reich.

To answer the question, we first need to understand how rainbows work, and then how a binary star system works. Once we figure out what kind of stars Tatooine orbits, we find that their rainbows would be quite lovely. However, if rain and rainbows were common, then they wouldn't need moisture farms. A successful moisture farm would suck all the rainbow-making droplets from the air, and ruin any possible rainbows.