On August 30, 2023, the 899th Martian day of the mission, NASA's Perseverance rover photographed the lower half of the Martian "Dust Demon" moving along the western edge of Mars' Jezero Crater. The video was sped up 20 times and consists of 21 frames taken at four-second intervals by one of the rover's navigation cameras. Geologists discovered the cyclone while conducting atmospheric soundings of Jezero Crater.
On August 30, NASA's Perseverance rover captured this "dust devil" at a place called "Thorofar Ridge" in Jezero Crater, moving from east to west at a speed of 12 miles (19 kilometers) per hour. Image source: NASA/JPL-Caltech
Tornadoes on Mars are much weaker and generally smaller than those on Earth, and are one of the mechanisms by which dust moves and is redistributed around Mars. Scientists study them to better understand the Martian atmosphere and improve their weather models.
On August 30, NASA's Perseverance rover captured this Martian dust devil moving from east to west at a speed of 12 miles (19 kilometers) per hour along the "Thorofar Ridge". The video was sped up 20 times and consists of 21 frames shot four seconds apart. The video has been enhanced to maximize detail. Image source: NASA/JPL-Caltech
Using data from the images, mission scientists determined that this particular dust devil was about 2.5 miles (4 kilometers) away at a site nicknamed "Thorofare Ridge" and moving from east to west at about 12 miles (19 kilometers) per hour. They calculated its width to be about 200 feet (60 meters). Although only 387 feet (118 meters) of the vortex's base were visible in the camera footage, scientists were able to estimate its full height.
"We can't see the top of the dust devil, but the shadow it casts gives a good indication of its height," said Mark Lemmon, a planetary scientist at the Space Science Institute in Boulder, Colorado, and a member of the Perseverance science team. "Most of them are vertical columns. If this dust devil is structured this way, its shadow would indicate that it is about 1.2 miles (about 2 kilometers) high."
On August 30, NASA's Perseverance rover captured this Martian dust storm, which was moving from east to west along the "Thorofar Ridge" at a speed of 12 miles (19 kilometers) per hour. This is a wider perspective, still frame. Source: NASA/JPL-Caltech
"Dust demons" also occur on Earth, forming dust tornadoes when rising warm air mixes with descending cold air. "Dust demons" on Mars can grow much larger than those on Earth. While they're most prominent in the spring and summer (it's currently summer in the northern hemisphere of Mars where Perseverance is located), scientists can't predict when they will show up at a particular location. Therefore, Perseverance and its companion NASA Mars rover Curiosity often monitor them from all directions, taking black and white images to reduce the amount of data sent to Earth.
A core goal of the Perseverance mission to Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize Martian geology and past climate, paving the way for human exploration of the Red Planet, and will also be the first mission to collect and store Martian rocks and detritus (rubble and dust).
In subsequent NASA missions, in partnership with the European Space Agency (ESA), a spacecraft will be sent to the Red Planet to collect these sealed samples from the surface and return them to Earth for in-depth analysis.
The Mars 2020 Perseverance mission is part of NASA's Moon-to-Mars exploration approach, which includes the Artemis lunar mission, which will help prepare for human exploration of Mars.
Management and operations of the Perseverance rover are handled by JPL, which is overseen on behalf of NASA by the California Institute of Technology (Caltech) in Pasadena, California.