The underside of the Mars dust devil was captured by NASA’s Perseverance rover traveling along the western rim of Jezero Crater on August 30, 2023, the mission’s 899th Martian day, or sol. The video, sped up 20 times, consists of 21 frames taken at four-second intervals by one of the rover’s navigation cameras.

Dust devils, much weaker and often smaller than Earth’s tornadoes, are one of the mechanisms that move and redistribute dust around Mars. Scientists study them to better understand the Martian atmosphere and improve weather models.

Using data from the images, mission scientists determined that this particular dust devil was about 2.5 miles (4 kilometers) away from us, at a location called Thorofar Ridge, and was moving east-west at about 12 mph (12 mph). . They estimated it was about 200 feet (60 meters) wide. Although only the lower 118 meters of the swirling vortex was visible in the camera frame, scientists were also able to estimate its full height.

“We can’t see the top of the dust devil, but the shadow it casts gives us a good idea of ​​its height,” said Mark Lemmon, a planetary scientist at the Space Science Institute in Boulder, Colorado, and one of the members. From the Perseverance science team. “Most are vertical pillars. If this dust devil were structured that way, its shadow would indicate it was about 1.2 miles (2 kilometers) high.”

Dust devils, also found on Earth, form when rising warm air mixes with descending columns of colder air. Martian versions can grow much larger than those found on Earth. And although they’re most common in spring and summer (summer is the season in the northern hemisphere of Mars, where Perseverance is located), scientists can’t predict when they’ll appear in a particular location. Perseverance and its counterpart, NASA’s Curiosity rover, regularly monitor all directions and take black-and-white images to reduce the amount of data sent back to Earth. Source