The Sun sets differently on Mars. Part of that is due to its distance from the star (an average of 142 million miles versus Earth’s roughly 93 million miles), but it also has to do with the planet’s atmosphere. A great example of the effects can be seen in the Red Planet’s noctilucent clouds.

Red-and-green-tinted clouds drift through the Martian sky in a new set of images captured by NASA's Curiosity rover using its Mastcam—its main set of "eyes." Taken over 16 minutes on Jan. 17 (the 4,426th Martian day,

"I'll always remember the first time I saw those iridescent clouds and was sure at first it was some color artifact."