Latin for “night shining,” noctilucent clouds (also known as twilight clouds) are responsible for Earth’s vibrant red, orange, and purple dawn and dusk skies. If the conditions are just right, they ...

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 ...