NASA’s Curiosity rover took a rare and stunning view of twilight clouds on Mars, commonly referred to as Noctilucent or night-shining clouds. The clouds are visible on Earth in the summer, but Curiosity has observed them on Mars for the fourth consecutive year.
The rover’s latest video, composed of shots taken within 16 minutes on January 17, features the iridescent red and green clouds sweeping across the Martian sky. The clouds appear only when they are high up in the sky at night, between altitudes of 60 to 80 km above the ground.
They were first detected by the 1997 Pathfinder mission and then observed by Curiosity in 2019. The twilights clouds are mostly made of carbon dioxide ice, with water ice clouds found below at approximately 50 km. The result of Mars’ carbon dioxide-dense atmosphere is the colorful iridescent effect. NASA posted the video on X, noting how these clouds are useful indicators of the Martian atmosphere and weather, with a caption reading, “Cloud gazing, on Mars.”
Watch:
Cloudgazing… on Mars! ☁️
@MarsCuriosity captured these colorful clouds drifting across the Martian sky. The iridescent, carbon dioxide ice formations offer clues about Mars’ atmosphere and weather: https://t.co/HAp2FDFjhk pic.twitter.com/DEWV477X01— NASA (@NASA) February 11, 2025
Mark Lemmon, an atmospheric scientist at the Space Science Institute, remembered the first time he saw the iridescent clouds, saying, “I’ll never forget the first time I saw those iridescent clouds and thought at first it was some colour artifact. Now it’s so predictable that we can schedule our shots ahead of time, the clouds appear at precisely the same time of year.”
While the view is breathtaking, researchers remain mystified as to why carbon dioxide ice clouds only occur in certain locations on Mars. They believe gravity waves might lead some areas to get cold enough for carbon dioxide to solidify into ice, though the dynamics of such waves on Mars are still unknown.
