NASA’s Curiosity rover reveals a stunning sunset on Mars

() — The Curiosity rover revealed a stunning postcard of a brilliant sunset on Mars.

NASA’s rover has been cruising the surface of Mars for more than 10 years, searching for answers about why the red planet went from hot and humid to a frozen desert. He has discovered intriguing rock formations, searched for signs of life, and climbed mount sharp in the center of Gale Crater.

But instead of continuing to focus on the nearly endless red stretch of rocks and dirt below its wheels, the rover has recently been looking up.

On February 2, Curiosity observed streaks of sunlight stretching across the horizon and illuminating a cloud bank as the sun set on Mars. It is the first time that the rays, known as crepuscular rays, have been seen so clearly on the red planet.

The rover is conducting a study of twilight clouds on Mars to follow up on its previous observations of clouds that glow at night. In 2021, Curiosity used its black-and-white navigation cameras to observe the structure of those clouds as they moved past Mars.

Clouds provide deeper insight into weather patterns and conditions. Scientists can use information about when and where clouds form on Mars to learn more about the planet’s atmospheric composition and temperatures, as well as wind.

The new survey, which began in January and will conclude later this month, uses the rover’s color camera on its mast to watch cloud particles grow.

On Mars, most clouds are made of frozen ice and float about 37 miles (60 kilometers) above the ground. But Curiosity detected clouds reaching a higher altitude, as seen in the new photo, leading researchers to believe they are made of frozen carbon dioxide ice, or dry ice. Scientists are still studying them to find out why this happens.

The Curiosity rover captured this iridescent plume-shaped cloud just after sunset on January 27. NASA/JPL-Caltech/MSSS

Curiosity captured a separate image of bright, iridescent clouds resembling feathers on January 27.

“Where we see iridescence, it means that the particle sizes of a cloud are identical to its neighbors in every part of the cloud,” said Mark Lemmon, an atmospheric scientist at the Institute for Space Sciences in Boulder, Colorado, in a statement. “By looking at the color transitions, we see that the size of the particles changes in the cloud. That tells us how the cloud is evolving and how its particles are changing size over time.”