Noctilucent clouds shimmer high in Mars' sky

Noctilucent, or "night-shining", clouds can be seen on Mars, just as they are on Earth. Nasa's Curiosity Mars rover imaged these high-altitude clouds on 17 May, 2019, using its navigation cameras. Noctilucent clouds are so-called because their great elevation means they can still be illuminated by the Sun after it has gone over the horizon. These clouds were just over 30km above the Martian surface.

Read more: The Red Planet's many hidden colours