This mosaic showing the Martian surface outside of
Jezero Crater was taken by NASA’s Perseverance on Dec. 25, 2024, at the site
where the rover cored a sample dubbed “Silver Mountain” from a rock likely
formed during Mars’ earliest geologic period.
NASA/JPL-Caltech/ASU/MSSS
The diversity of rock types along the rim of Jezero Crater offers a wide
glimpse of Martian history.
Scientists with NASA’s Perseverance
rover are exploring what they consider a veritable Martian cornucopia full of
intriguing rocky outcrops on the rim of Jezero Crater. Studying rocks,
boulders, and outcrops helps scientists understand the planet’s history,
evolution, and potential for past or present habitability. Since January, the
rover has cored five rocks on the rim, sealing samples from three of them in
sample tubes. It’s also performed up-close analysis of seven rocks and analyzed
another 83 from afar by zapping them with a laser. This is the mission’s
fastest science-collection tempo since the rover landed on the Red Planet more
than four years ago.
Perseverance climbed the western
wall of Jezero Crater for 3½ months, reaching the rim on Dec. 12, 2024, and is currently exploring a roughly 445-foot-tall
(135-meter-tall) slope the science team calls “Witch Hazel Hill.” The diversity
of rocks they have found there has gone beyond their 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.”
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.
NASA/JPL-Caltech
That’s because Jezero Crater’s western rim contains tons of fragmented
once-molten rocks that were knocked out of their subterranean home billions of
years ago by one or more meteor impacts, including possibly the one that
produced Jezero Crater. Perseverance is finding these formerly underground
boulders juxtaposed with well-preserved layered rocks that were “born” billions
of years ago on what would become the crater’s rim. And just a short drive away
is a boulder showing signs that it was modified by water nestled beside one
that saw little water in its past.
Oldest Sample
Yet?
Perseverance collected its first
crater-rim rock sample, named “Silver Mountain,” on Jan. 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 Feb. 4 and Feb. 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.
Sealing the “Green Gardens” sample — collected by
NASA’s Perseverance Mars rover from a rock dubbed “Tablelands” along the rim of
Jezero Crater on Feb. 16, 2025 — presented an engineering challenge. The sample
was finally sealed on March 2.
NASA/JPL-Caltech/ASU/MSSS
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.
Up Next
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
A key objective for Perseverance’s
mission on Mars is astrobiology, including the search for signs of ancient microbial
life. The rover is characterizing the planet’s geology and past climate, to
help pave the way for human exploration of the Red Planet and is the first
mission to collect and cache Martian rock and regolith.
NASA’s Mars Sample Return Program,
in cooperation with ESA (European Space Agency), is designed to send spacecraft
to Mars to collect these sealed samples from the surface and return them to
Earth for in-depth analysis.
The Mars 2020 Perseverance mission
is part of NASA’s Mars Exploration Program portfolio and the agency’s Moon to
Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of
the Red Planet.
NASA’s Jet Propulsion Laboratory,
managed for the agency by Caltech in Pasadena, California, built and manages
operations of the Perseverance rover.
For more about Perseverance:
https://science.nasa.gov/mission/mars-2020-perseverance
Source: NASA’s Perseverance Mars Rover Studies Trove of Rocks on Crater Rim - NASA
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