NASA’s Perseverance rover is discovering a treasure trove of diverse ancient rocks on Jezero Crater’s rim, some possibly altered by water and dating back billions of years.
After overcoming tricky sampling challenges, scientists are thrilled by what these unique Martian specimens might reveal.
Martian Rock Rush on Jezero’s Rim
NASA’s Perseverance rover is exploring what scientists are calling a treasure trove of fascinating rock formations along the rim of Jezero Crater. These rocky outcrops, boulders, and layered surfaces offer valuable clues about Mars’ ancient history, how the planet has changed over time, and whether it may have once supported microbial life.
Since January, Perseverance has collected core samples from five different rocks, successfully sealing three of them in tubes for potential return to Earth. The rover has also conducted close-up studies of seven rocks and used its laser to analyze 83 more from a distance. This marks the fastest pace of scientific work since the rover touched down on Mars more than four years ago.
After spending over three months climbing the western wall of Jezero Crater, Perseverance reached the rim on December 12, 2024. It is now exploring a 445-foot-high slope known to the science team as Witch Hazel Hill, where the variety of rock types has far exceeded expectations.
“During previous science campaigns in Jezero, it could take several months to find a rock that was significantly different from the last rock we sampled and scientifically unique enough for sampling,” said Perseverance’s project scientist, Katie Stack Morgan of NASA’s Jet Propulsion Laboratory in Southern California. “But up here on the crater rim, there are new and intriguing rocks everywhere the rover turns. It has been all we had hoped for and more.”
What makes this area so special is its explosive past. Jezero Crater’s western rim holds a mix of shattered, once-molten rocks that were blasted from deep underground by ancient meteor impacts—possibly the one that created the crater itself. These ancient fragments now sit beside layered rocks that formed on the surface billions of years ago. In some places, Perseverance has even found rocks shaped by water sitting right next to ones that remained dry for most of their existence.
One of Perseverance’s hazard cameras captured the rover’s coring drill collecting the “Main River” rock sample on “Witch Hazel Hill” on March 10, 2025, the 1,441st Martian day, or sol, of the mission. Credit: NASA/JPL-Caltech
Oldest Martian Sample Yet?
Perseverance collected its first crater-rim rock sample, named “Silver Mountain,” on January 28. (NASA scientists informally nickname Martian features, including rocks and, separately, rock samples, to help keep track of them.) The rock it came from, called “Shallow Bay,” most likely formed at least 3.9 billion years ago during Mars’ earliest geologic period, the Noachian, and it may have been broken up and recrystallized during an ancient meteor impact.
About 360 feet (110 meters) away from that sampling site is an outcrop that caught the science team’s eye because it contains igneous minerals crystallized from magma deep in the Martian crust. (Igneous rocks can form deep underground from magma or from volcanic activity at the surface, and they are excellent record-keepers — particularly because mineral crystals within them preserve details about the precise moment they formed.) But after two coring attempts (on February 4 and February 8) fizzled due to the rock being so crumbly, the rover drove about 520 feet (160 meters) northwest to another scientifically intriguing rock, dubbed “Tablelands.”
Data from the rover’s instruments indicates that Tablelands is made almost entirely of serpentine minerals, which form when large amounts of water react with iron- and magnesium-bearing minerals in igneous rock. During this process, called serpentinization, the rock’s original structure and mineralogy change, often causing it to expand and fracture. Byproducts of the process sometimes include hydrogen gas, which can lead to the generation of methane in the presence of carbon dioxide. On Earth, such rocks can support microbial communities.
Coring Tablelands went smoothly. But sealing it became an engineering challenge.
The Sealing Challenge: Enter the Flick Maneuver
“This happened once before, when there was enough powdered rock at the top of the tube that it interfered with getting a perfect seal,” said Kyle Kaplan, a robotics engineer at JPL. “For Tablelands, we pulled out all the stops. Over 13 sols,” or Martian days, “we used a tool to brush out the top of the tube 33 times and made eight sealing attempts. We even flicked it a second time.”
During a flick maneuver, the sample handling arm — a little robotic arm in the rover’s belly — presses the tube against a wall inside the rover, then pulls the tube away, causing it to vibrate. On March 2, the combination of flicks and brushings cleaned the tube’s top opening enough for Perseverance to seal and store the serpentine-laden rock sample.
Eight days later, the rover had no issues sealing its third rim sample, from a rock called “Main River.” The alternating bright and dark bands on the rock were like nothing the science team had seen before.
Still More Secrets in the Rocks
Following the collection of the Main River sample, the rover has continued exploring Witch Hazel Hill, analyzing three more rocky outcrops (“Sally’s Cove,” “Dennis Pond,” and “Mount Pearl”). And the team isn’t done yet.
“The last four months have been a whirlwind for the science team, and we still feel that Witch Hazel Hill has more to tell us,” said Stack. “We’ll use all the rover data gathered recently to decide if and where to collect the next sample from the crater rim. Crater rims — you gotta love ’em.”
More About Perseverance
NASA’s Perseverance rover is a key part of the Mars 2020 mission, designed to explore the Red Planet as part of NASA’s broader Moon to Mars exploration strategy. Built and operated by NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, the rover landed in Jezero Crater in 2021 to search for signs of ancient microbial life—a core goal of its astrobiology mission.
Perseverance is studying Mars’ geology and past climate to help scientists better understand the planet’s history and its potential to support life. It is also paving the way for future human exploration by testing new technologies and preparing a detailed environmental picture of the Martian surface.
Notably, Perseverance is the first mission to collect and cache samples of Martian rock and soil (regolith). These sealed samples are intended for retrieval by a future mission through the Mars Sample Return program, a joint effort between NASA and the European Space Agency (ESA), which aims to bring the material back to Earth for detailed analysis.
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