NASA’s Curiosity views first ‘sun rays’ on Mars

Martian sunsets are uniquely moody, however NASA’s Curiosity rover captured one final month that stands out. Because the sun descended over the horizon on Feb. 2, rays of sunshine illuminated a financial institution of clouds. These “sun rays” are often known as crepuscular rays, from the Latin phrase for “twilight.” It was the primary time sun rays have been so clearly considered on Mars.

Curiosity captured the scene through the rover’s latest twilight cloud survey, which builds on its 2021 observations of noctilucent, or night-shining, clouds. Whereas most Martian clouds hover not more than 37 miles (60 kilometers) above the bottom and are composed of water ice, the clouds within the newest pictures seem like at a higher altitude, the place it is particularly chilly. That means these clouds are made from carbon dioxide ice, or dry ice.

As on Earth, clouds present scientists with complicated however essential data for understanding the climate. By when and the place clouds type, scientists can be taught extra in regards to the Martian environment’s composition and temperatures, and the winds inside it.

The 2021 cloud survey included extra imaging by Curiosity’s black-and-white navigation cameras, offering an in depth have a look at a cloud’s construction because it strikes. However the current survey, which started in January and can wrap up in mid-March, depends extra typically on the rover’s coloration Mast Digital camera, or Mastcam, which helps scientists see how cloud particles develop over time.

Along with the picture of sun rays, Curiosity captured a set of colourful clouds formed like a feather on Jan. 27. When illuminated by daylight, sure sorts of clouds can create a rainbowlike show referred to as iridescence.

“The place we see iridescence, it means a cloud’s particle sizes are equivalent to their neighbors in every a part of the cloud,” mentioned Mark Lemmon, an atmospheric scientist with the House Science Institute in Boulder, Colorado. “By coloration transitions, we’re seeing particle size altering throughout the cloud. That tells us about the way in which the cloud is evolving and the way its particles are altering measurement over time.”

Curiosity captured each the sun rays and iridescent clouds as panoramas, every of which was stitched collectively from 28 pictures despatched to Earth. The photographs have been processed to emphasise the highlights.