A new paper Describing the first 216 days of Perseverance’s mission at Jezero Crater, the newest rover on Mars appears to be in a “dust storm track” that spans the planet from north to south. Jezero crater has a particularly high dust and wind activity.
“Jezero Crater may be in one of the most active dust sources on Earth,” said Manuel de la Torre Juarez, deputy principal investigator of Perseverance’s weather instruments. “Everything we learn about dust will be useful for future missions.”
The research team — led by Claire Newman from Aeolis Research – reports that an average of four dust vortices pass the rover daily. There is a period around noon local time when typically more than one dust devil per hour zooms near the rover. In addition, strong gusts produced by daytime convection cells over the crater often lifted airborne dust over a wide area, creating a localized dust cloud. One such event covered ten times the surface area of the largest dust devil.
“Every time we land in a new spot on Mars, it’s an opportunity to better understand the weather on the planet,” Newman said, adding that more dusty weather may be on the way. “We had a regional dust storm in January, but we’re still in the middle of the dust season, so there’s a good chance we’ll see more dust storms.”
Not only has the rover detected hundreds of dust devils since it landed in Jezero Crater in February 2021, but Perseverance also captured the first ever video of wind gusts lifting a massive dust cloud from Mars.
The rover contains a series of sensors, the MEDA (or the Mars Environmental Dynamics Analyzer). MEDA includes wind sensors, light sensors that can detect vortices as they scatter sunlight around the rover, and a sky-facing camera for capturing images of dust and clouds. The rover’s array of cameras is also used to monitor the weather and look for passing dust devils.
This sequence of images from a navigation camera aboard Perseverance shows a gust of wind sweeping dust across the Martian plain beyond the rover’s tracks on June 18, 2021 (the 117th sol, or Mars day, of the mission). The dust cloud in this GIF was estimated to be 4 square kilometers; it was the first wind-lit dust cloud of its size ever captured on Mars. Credit: NASA/JPL-Caltech/SSI Full Image Details
“We think these gusts are uncommon, but may be responsible for much of the background dust that’s constantly floating in the Martian atmosphere,” Newman said.
Because Perseverance is nuclear-powered, the rover team doesn’t have to worry about dust collecting on solar panels and affecting the mission. But it appears that there is more dust going up into the air at Jezero Crater, Newman said in a press release, although “average wind speeds are lower there and peak wind speeds and whirlwind activity are comparable to Elysium Planitia,” where InSight is located, about 3,452 km (2,145 miles) away.
While wind and dust are common throughout Mars, the dust storm trail in Jezero crater may be due to factors such as the roughness of the surface, which can make it easier for the wind to lift dust. While the dust devils are scientific and aesthetically pleasing, sand carried by these storms has damaged MEDA’s two wind sensors.
The team said they suspect the grains of sand damaged the thin wiring on the wind sensors, which protrude from Perseverance’s mast. These sensors are particularly vulnerable because they must remain exposed to the wind in order to measure correctly. The Curiosity rover also had wind sensors damaged by dust and debris picked up during its landing at Gale Crater.
Even with additional protective coatings on MEDA’s wires, damage still occurred, highlighting the harmful nature of the Martian dust.
De la Torre Juarez said the team is testing software changes to keep the wind sensors working.
“We have collected a lot of great scientific data,” said de la Torre Juarez. “The wind sensors, ironically, are seriously affected because we got what we wanted to measure.”
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