[OokieWonderslug (OP)]

So I read that the atmosphere of Mars is equal to Earth's at 100,000 feet. If that is the case, why does Mars have a greyish, purplish sky? At 100,000 feet the sky is jet black on Earth. Why is there a difference? I can't seem to figure it out. Any help?

[Kryptid]

Here's an interesting read on the subject: http://serious-science.org/what-color-is-the-sky-on-mars-7310

Apparently, the sky on Mars is pretty dark when it's free of dust:

Spirit and Opportunity reported “bluish-black” or “black” skies in dust-free atmospheres. However, most of the time, Mars’ atmosphere is loaded with lots of dust, so this is not the common aspect of the sky.