NASA’s Curiosity rover photographs cloud rays on Mars

The Curiosity rover, which has been on Mars for more than ten years, loves sunsets and twilight. A month ago, the NASA rover photographed so-called cloud rays. That was the first time this phenomenon had been so clearly observed on the red planet.

Curiosity made the photo with cloud rays on February 2, or the 3730th sol of the mission. A sol is the name for a Martian day, which lasts slightly longer than a day on Earth, namely 24 hours, 39 minutes and 35 seconds. Cloud rays are also called solar harps, crepuscular rays or crepuscular rays.

The photo is part of a study into clouds during twilight on Mars that began in January. This research ended in the middle of this month and mainly uses a color camera, the Mast Camera. Using a color camera helps scientists see how cloud particles grow over time. In 2021, the rover will also have… observations made of night clouds. Those observations from two years ago mainly used the rover’s black-and-white navigation cameras.

Most clouds on the red planet are no higher than 60km above the surface and are made of water ice, but the clouds in the photo appear to be even higher, according to NASA. Because it is even colder there, the clouds would disappear, for example dry ice can exist.

On January 27, Curiosity photographed a set of feather-shaped clouds with rainbow-like colors caused by the sun. By studying these colors, scientists can say something about the size of the particles in the clouds and how they grow over time.

Both photos were created by combining 28 individual photos into a large panorama. The images have been edited to emphasize the highlights a bit more.