A year since touchdown: What has NASA's Perseverance rover been up to?
On February 18, 2021, the spacecraft carrying NASA's $2.7 billion robotic explorer named Perseverance, placed the rover gently on Mars, after what NASA engineers call "seven minutes of terror". NASA's most enthusiastic effort in decades to study if there was ever life on the red planet completes a year today, what Jennifer Trosper, Mars 2020 Project Manager, NASA/JPL, calls the "landiversary".
"For the very first time, we were able to take images and videos of the rover and the parachute while we were landing and we've some iconic images that we'll look at for years to come," Trosper said in 'Roving with Perseverance: Findings from One Year on Mars', a live public talk that was streamed a few hours ago.
Trosper mentioned that sharing the Perseverance's landing success with people all over the world was a highlight. "It was also more special because the time of the pandemic was really difficult for everyone. And we wanted to offer something exciting and hopeful. It was thrilling for us to be able to share that success with all of the people who were there with us and rooting us on," she said.
Since landing on the barren planet, Perseverance, nicknamed Percy, has had a more productive year than you or me. Percy has traveled more than three kilometers across rocky terrain, recorded the first flight on the planet by helicopter, and collected six precious rock samples.
Though Perseverance is currently nestled in a 28-mile-wide crater known as Jezero, the rover was designed to look for signs of human life in an ancient delta, where a river that once flowed into the crater deposited rocks and sediments. It hasn't reached the delta yet.
The rover surprised scientists
Percy has, instead, made some wonderful discoveries about the crater. Some researchers thought that Jezero's floor would be made of sedimentary rock, but Percy proved them wrong. The rover found that the crater's floor was made of igneous rocks that formed as molten rock cooled and solidified billions of years ago.
This particular discovery was important as igneous rocks help scientists analyze the radioactive decay of elements inside them to determine how old the rocks are. Researchers will be able to date rocks from specific places for the first time, if and when Perseverance's samples return to Earth.
A month after landing, Perseverance drilled its first pair of cores into a rock formation called Maaz. It then drove south and west around a dune-ridden area called Seitah and collected two more pairs of samples. Seitah's rocks were assumed to be sedimentary too, until Perseverance discovered that they, too, were igneous.
Like the Maaz rocks, the Seitah rocks too show signs of interaction with water in the past. Eva Scheller, a geologist at the California Institute of Technology in Pasadena, reported that they may even contain organic molecules like those seen in some Martian meteorites.
Will Percy understand the assignment?
Scientists are awaiting Perseverance's entry to the long-awaited delta. The rover has only about one Earth year left to accomplish the tasks on its list, which include getting to the delta, collecting samples there, and driving up onto the crater rim to place them somewhere for pick-up. However, Perseverance is working faster than NASA’s previous Mars rover, Curiosity, which has been exploring Gale Crater since it landed in 2012.
Perseverance has faced some minor glitches—pebbles blocked Perseverance's drilling mechanism in January—but it shook them loose and proceeded about its work.
Meanwhile, Perseverance's little friend, a small robotic helicopter called Ingenuity, has so far made 19 flights and traveled more than 3.8 kilometers. If it continues to survive, it will be used to monitor routes that the rover might take once it gets to the Jezero delta to collect more cores.
Once Perseverance gets to the delta, the most surprising discovery would be images of what looked to be microscopic fossils. If that happens, "we have to start asking whether some globs of organic matter are arranged in a shape that outlines a cell,” Tanja Bosak, a geobiologist at the Massachusetts Institute of Technology, told The New York Times.
Currently, there is barely any evidence on when chemical processes came together to form the first cell. "And so we may be looking at something that was just learning to be life," added Dr. Bosak.