NASA’s Curiosity rover has captured stunning images of iridescent, red-and-green-tinted clouds drifting across the Martian sky. These noctilucent, or “night-shining,” clouds were observed on January 17, 2025, during the early fall season in Mars’ southern hemisphere. The phenomenon occurs when high-altitude clouds, composed of carbon dioxide ice crystals, are illuminated by the setting sun, creating a shimmering display of colors.
The images, taken over a 16-minute period using Curiosity’s Mastcam, reveal clouds floating approximately 37 to 50 miles (60 to 80 kilometers) above the Martian surface. Some of these ice crystals can be seen descending as white plumes, evaporating as they encounter warmer atmospheric layers closer to the surface.
Atmospheric scientist Mark Lemmon from the Space Science Institute noted the predictability of these iridescent clouds, stating, “Now it’s become so predictable that we can plan our shots in advance; the clouds show up at exactly the same time of year.”
Studying these clouds provides scientists with valuable insights into the particle size and growth rate in Martian clouds, enhancing our understanding of the planet’s atmospheric dynamics. The consistent appearance of these clouds during specific Martian seasons suggests underlying atmospheric patterns that are still being explored.