Roger Wiens, a planetary scientist and Mars rover expert at Purdue University, with a topographical model of Mars and a photo of Curiosity. Credit: Purdue University/John Underwood
Key Points:
- Scientists have captured the sounds of a dust devil on Mars for the first time.
- The recording can help scientists better understand Martian atmosphere and weather.
- Researchers say sound is one of the most vital tools on Perseverance.
The decision to equip Perseverance with the first working microphone on a rover has paid its dividends. In a new study published in Nature Communications, scientists explain how they captured the first-ever audio recording of an extraterrestrial whirlwind.
The microphone, part of Perseverance’s SuperCam, is not on continuously; rather, it records for about three minutes every couple of days. Getting the whirlwind recording was lucky, though not necessarily unexpected, according to Roger Wiens, SuperCam principal investigator.
In the Jezero Crater, where Perseverance landed, the team has observed evidence of nearly 100 dust devils—tiny tornadoes of dust and grit—since the rover’s landing. This is the first time the microphone was on when one passed over the rover.
“We can learn a lot more using sound than we can with some of the other tools,” Wiens said. “They take readings at regular intervals. The microphone lets us sample, not quite at the speed of sound, but nearly 100,000 times a second. It helps us get a stronger sense of what Mars is like.”
The sound recording of the dust devil, taken together with air pressure readings and time-lapse photography, help scientists understand the Martian atmosphere and weather.
“We could watch the pressure drop, listen to the wind, then have a little bit of silence that is the eye of the tiny storm, and then hear the wind again and watch the pressure rise,” Wiens said. “The wind is fast—about 25 miles per hour, but about what you would see in a dust devil on Earth. The difference is that the air pressure on Mars is so much lower that the winds, while just as fast, push with about 1% of the pressure the same speed of wind would have back on Earth. It's not a powerful wind, but clearly enough to loft particles of grit into the air to make a dust devil.”
The information indicates that future astronauts will not have to worry about gale-force winds blowing down antennas or habitats, but the wind may have some benefits. The breezes blowing grit off the solar panels of other rovers—especially Opportunity and Spirit—may be what helped them last so much longer.
“Those rover teams would see a slow decline in power over a number of days to weeks, then a jump. That was when wind cleared off the solar panels,” Wiens said.
Information provided by Purdue University.