As seen on Space, the six-wheeled remote rover witnessed a Martian dust devil moving from east to west across the desolate, rocky landscape on August 30, 2023.
The video, which NASA has sped up 20 times, comprises 21 frames taken four seconds apart by the rover. The video has also been digitally enhanced to show the dust devil in greater detail.
“Using data from the imagery, mission scientists determined that the dust devil was about 2.5 miles (four kilometers) away, at a location nicknamed ‘Thorofare Ridge,’ and moving east to west at a clip of about 12 miles per hour (19 kilometers per hour). They calculated its width to be about 200 feet (60 meters). While only the bottom 387 feet (118 meters) of the swirling vortex are visible in the camera frame, scientists used the dust devil’s shadow to estimate its full height at about 1.2 miles (two kilometers),” writes NASA’s Jet Propulsion Laboratory (JPL).
The images, captured on the 899th Martian day, or sol, of the Perseverance mission were shot by one of the rover’s Navcams.
Perseverance landed on Mars in February 2021 and is searching for signs of ancient life on Mars and collecting samples to return to Earth. The rover has seen some amazing sights on Mars in its two-plus years of service.
NASA explains that dust devils are “much weaker and generally smaller” than tornadoes on Earth and that dust devils are one of the red planet’s natural mechanisms that redistribute dust around Mars. Scientists study Martian twisters to learn more about Mars’ atmosphere and build more accurate weather models.
Dust devils are not unique to Mars, they occur on Earth, too. Martian versions can grow much larger than those on Earth, but the mechanisms by which they form are similar. Dust devils occur when rising cells of warm air mix with descending columns of cooler air. Perseverance and the other Mars rover, Curiosity, are constantly on the look-out for dust devils. NASA explains that they are more common during the spring and summer months, which is when Perseverance spotted the featured event as the rover is exploring Mars’ northern hemisphere.