This might, at first glance, look like an everyday sky. But these aren’t Earth clouds; they’re Martian clouds – as photographed by Natalie Moore (Member 11,271) using cameras aboard NASA’s Curiosity rover.

Natalie takes cloudspotting to new frontiers as the operator of Curiosity’s Mastcam, its main set of ‘eyes’. Natalie and her team have been directing the rover’s eyes upwards in a series of ‘cloud campaigns’ over the past five of our Earth years. Martian cloudspotting like this has helped us learn more about the Martian atmosphere.

‘We just ended another cloud campaign in Gale crater,’ Natalie told us, ‘and we got some amazing images of noctilucents!’ These are high-altitude Martian clouds (up at around 35-50 miles, or 60-80 kilometres), which are comparable to the extreme-altitude noctilucent clouds found on Earth. The Martian ones spotted by Curiosity here are producing delicate mother-of-pearl colours, which you might just be able to make out, as they diffract the fading light of nightfall. High Martian clouds like these are made not of water, like ours, but of frozen carbon dioxide. As Spock would have put it, ‘They’re clouds, Jim, but not as we know them.’

NASA/JPL-Caltech/MSSS/SSI