Purple Planets?

[junkheap]

I was wondering if it's possible for there to be a purple planet or moon? I was just wondering because of the disappointing lack of purple planets or moons in our solar system.

Whether it's a gas giant or rocky planet, what could be the atmospheric of geological make-up of such a planet?

Would such a planet be rare?

 

[OleNewt]

If it were a rocky planet, at this point in time it'd probably not matter what the planet was made of since we could never see it as anything more than a small dot and perhaps not even tell what sort of elements were present. However, if we do or eventually will get to a point where we can visually capture such planets they would most likely be covered by liquid water with dissolved potassium permanganate (forming a purplish-black solution) or liquid alcohol with dissolved iodine (a purplish-pink solution). In the absence of these two, perhaps it's a good indication of Retinal-based plantlife.

If it were a gaseous planet, it would probably be clouds of iodine.