What's in a Color?

I've always been fascinated by why planets look the colors they do. Mars is red because of iron oxide - basically rust! Jupiter has those bands because of different chemical compositions in its atmosphere. Saturn's yellow comes from ammonia crystals in its upper atmosphere.

It Takes All Sorts

Each planet's color tells us something about its composition and history. Mercury is gray because it's basically a big rock. Neptune looks blue because of methane in its atmosphere. Venus is yellowish-white because of sulfur clouds.