Dangerous Landing of Perseverance Mars Rover is a Critical 7 Minutes for WashU Professor

    By Kathleen Berger, Executive Producer for Science & Technology

    As NASA anxiously awaits the landing of the Perseverance rover on Mars, a Washington University in St. Louis professor is feeling the excitement mixed with anxiety knowing from firsthand accounts how rover landings are the most dangerous part of the journey. Raymond E. Arvidson, PhD, James S. McDonnell Distinguished University Professor, has played a leading role in Mars rover and lander missions spanning many years.

    Arvidson is the deputy principal investigator for the highly successful Mars Exploration Rover missions – Spirit and Opportunity. He’s currently a NASA science team member for the Curiosity rover in charge of path planning. And he’s the director of the NASA Planetary Data System (PDS) Geosciences Node located at Washington University in St. Louis. This means Arvidson’s campus facility will be archiving all the Perseverance data.

    Arvidson said successfully launching Perseverance from Earth on July 30, 2020 and traveling nearly seven months through space have challenges, but nothing as dangerous as landing on Mars. The nail-biting descent is February 18, 2021.

    NASA scientists refer to the Perseverance rover landing as “seven minutes of terror” because it’s the most critical and dangerous part of the mission. Entering the Martian atmosphere at more that 12,000 miles per hour, Perseverance will streak across the sky like a meteor for seven minutes before finally touching down. If any one thing doesn’t work right, it’s game over!

    “It’s all done automatically. You come in through the atmosphere at miles per second and you use an aeroshell and a parachute, and then the sky crane to land wheels first. There’s a cable that comes down about 30 yards,” said Arvidson. “Suspended, then the cables are cut automatically and the sky crane goes off, and then you got a rover on the surface. That’s the most difficult part.”

    Arvidson is among the NASA scientists who helped choose Jezero Crater as the landing site.

    “With this big eroded delta, we’re continuing to provide images, other pieces of information that help the science team once they land and start traversing on where to go to get the best samples,” Arvidson said.

    Perseverance will continue the success of other Mars rovers by conducting a detailed search for evidence of ancient microbial life on Mars. The new high-tech rover is NASA’s most sophisticated rover ever built and it’s the biggest to ever land on the Red Planet. Perseverance is the first part of a multi-billion dollar effort to secure Martian rock and regolith (broken rock and soil) samples for possible return to Earth.  The rover will collect and deposit the samples for retrieval by a future fetching rover. Arvidson is part of the team creating those specifications.

    Arvidson explained he is part of a community of scientists spending many years trying to get NASA and the United States Government to support the return of Martian samples to Earth. Arvidson said he fought for this opportunity since the 1970’s.

    “The whole idea is to go to a place (on Mars), drill and get the samples. Put them out on the surface to be returned by a later mission,” said Arvidson. “Why is it so important? Because you can do many, many more very detailed analysis in the laboratory than you can do from a rover.”

    The name “Perseverance” seems fitting for the role Arvidson has played.

    “Partly because it took so long to get this mission, so there was perseverance,” he said. “This is a mission I’ve been pushing for since the 70’s and it’s the first step towards getting really characterized samples from known geological environments back on Earth.”