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NASA’s Mars rover Perseverance may have found a crucial clue central to its Mars mission: geological evidence that suggests life existed on the Red Planet billions of years ago.
On July 18, the robotic probe discovered a vein-filled red rock that appears dotted with leopard-print spots, which could indicate ancient chemical reactions within the rock that allowed microorganisms to live.
“These spots are a big surprise,” David Flannery, an astrobiologist at Queensland University of Technology in Australia and a member of NASA’s Perseverance science team, said in a statement. “On Earth, these kinds of features in rocks are often associated with the fossil record of microorganisms living below the surface.”
This research is still in its early stages, but NASA scientists aren’t yet sure how the rock formed, so they need to study it on Earth, but the arrowhead-shaped specimen could help the Perseverance team figure out whether Mars was once a habitable planet.
“We are incredibly excited to get this sample!” Bryony Hogan, professor of planetary science at Purdue University in West Lafayette, Indiana, and co-investigator of the Perseverance rover mission, said in an email.
“This rock is exactly what we came to Mars to sample, and we can’t wait to get back to Earth and get it into our lab,” she said. “This is exactly the potential microbial biosignature that NASA envisioned when they planned the Mars 2020 mission, and we used every instrument on board to find and understand this rock.”
Nickname Rock Cheyava Falls This waterfall, one of the Grand Canyon’s waterfalls, intrigues scientists for a variety of reasons.
White veins of calcium sulfate are clear evidence that water, essential for life, once flowed through the rocks. The rover used its Scanning for Habitable Environments, Scanning for Organics and Chemicals by Raman Spectroscopy and Luminescence, or SHERLOC (Scanning for Habitable Environments, Scanning for Organics and Chemicals) instrument to identify organic carbon-based molecules in the rocks.
And the irregularly shaped leopard spots examined by the rover’s PIXL instrument detected iron and phosphate, said Morgan Cable, a research scientist on the rover team. video Shared by NASA’s Jet Propulsion Laboratory, Pasadena, California.
NASA/JPL-Caltech/ASU/MSSS
The Perseverance rover has captured 360-degree panoramic images of a region on Mars known as the Bright Angel, where a river once flowed billions of years ago.
“We’ve never seen all three of these things together on Mars before,” Cable said.
The team also found the possible presence of hematite among the white bands of calcium sulfate in the rock, one of the minerals responsible for Mars’ distinctive red color.
Leopard spots may have formed when a chemical reaction with hematite turned the rock from red to white, releasing iron and phosphates that could form the black rings — a reaction that could also provide an energy source for the microbes.
“Cheyaba Falls are the most mysterious, complex and potentially important rocks Perseverance has explored to date,” Ken Farley, Perseverance’s project scientist and professor of geochemistry at the California Institute of Technology in Pasadena, said in a statement.
The team also found millimeter-sized crystals of olivine in the same rock. Previously Detected Perseverance found olivine in other parts of the crater, a mineral formed from magma, and the team says the olivine in the Cheyaba Falls rocks could be linked to rocks that formed in other parts of the valley.
The rover team is addressing a number of questions as they study the rocks and try to understand the processes by which they were formed.
Cheyava Falls likely began as a mixture of sedimentary mud and organic compounds that eventually hardened into rock. Water may have then seeped through cracks in the rock, depositing minerals to form calcium sulfate veins and leopard spots.
But it’s also possible that the scorching heat of Mars caused olivine and sulfates to become part of the rocks, undergoing non-biological chemical reactions that led to the formation of the leopard spots.
Since landing on Mars, Perseverance has been traversing Jezero Crater and exploring an ancient river delta in search of microfossils of past life. The rover has collected samples along the way that it may be able to bring back to Earth on a future mission.
Most recently, Perseverance explored the northern end of the Neretva Canyon, an ancient river valley that fed water into Jezero Crater more than 3 billion years ago, where it discovered the Ceyava Waterfall. The rover landed inside the crater in February 2021 and explored remains of an ancient lake.
NASA/JPL-Caltech/MSSS
Perseverance took this selfie, which is made up of 62 individual images, on July 23.
Geologists on the rover team are eager to use Perseverance to study rocks that may have been created or altered by water on Mars in the past, which is why Cheyaba Falls intrigued them.
“We designed Perseverance’s route to take it to areas with potentially fascinating scientific samples,” Nicola Fox, associate administrator for NASA’s Science Mission Directorate, said in a statement. “Its journey through the Neretva Valley riverbed paid off by discovering something never seen before, which will provide our scientists with many research opportunities.”
In April, NASA announced that the original, complex, multi-mission design for a program called Mars Sample Return, aimed at bringing Perseverance samples back to Earth, had been finalized. No longer feasible IDue to budget cuts and delayed return, the current structure remains in place.
NASA is calling on its centers and industry to develop a new plan that combines innovation with lessons learned from proven technologies. NASA leaders hope to bring samples back to Earth by the 2030s with less complexity, cost and risk than originally planned, and NASA hopes to have answers by the fall about how best to bring samples back from Mars, NASA Administrator Bill Nelson said at a press conference in April.
NASA/JPL-Caltech/ASU/MSSS
Perseverance collected rock samples from Cheyaba Falls on July 21.
Meanwhile, Perseverance continues its important research work on Mars and is expected to begin its climb to the rim of Jezero Crater soon.
“This discovery comes at a critical time as NASA reexamines how best to bring these samples back from Mars through its Mars Sample Return mission,” Hogan said. “It shows just how important and unique our sample set is.” “And how much we might learn about the beginnings of life on planets like Earth. It also feels very fitting that Jezero has one final surprise in store for us before we leave the ancient river and lake deposits on the crater floor and begin our climb up the rim.”
The Perseverance team says bringing back samples is the only way to know if life ever existed on Mars.
“We shone a laser and X-rays on the rocks and took images from just about every angle imaginable, literally day and night,” Farley said. “Scientifically, there’s nothing more that Perseverance can provide. To fully understand what really happened in the Martian river valley in Jezero Crater billions of years ago, we need to bring samples of Cheyaba Falls back to Earth and study them with the powerful instruments available in our laboratories.”
