WASHINGTON D.C. — The Perseverance Rover connected Mars whitethorn person stumbled upon nan oldest rocks humans person ever seen and, possibly, grounds of a caller mounting that ancient Martian organisms could person inhabited, if they ever existed.
“This is really 1 of nan astir breathtaking things that this ngo is going to do, is to beryllium looking astatine rocks that were formed truthful early successful nan history of nan star system,” said Caltech geochemist Kenneth Farley during a December 12 news briefing astatine a gathering of nan American Geophysical Union. “Almost nan dawn of nan star system.”
Possibly nan oldest rocks we’ve seen
For astir of its mission, Perseverance has been poking astir wrong Jezero Crater, probing and sampling rocks that are astir apt astir 3.7 cardinal years aged (SN: 2/17/23). The rocks astatine nan rim, however, are astir apt overmuch older, having been uplifted by nan effect that created nan crater.
On December 11 — pursuing a slippery, three-month-long, 500-meter climb from nan crater level — nan robotic explorer yet surmounted that crater’s rim, aft weeks of studying nan precocious area’s geology. And each that exploration appears to person paid off.
“The rocks that we are now exploring are apt older than 4 cardinal years,” said Farley, who is besides task intelligence for nan Mars 2020 Mission that brought nan rover to nan planet. “These are amongst nan oldest rocks successful nan star system, and they’re older than immoderate rocks that beryllium connected Earth.” Part of nan logic for that is that overmuch of Earth’s ancient aboveground has been destroyed astatine subduction zones, wherever one tectonic sheet plunges beneath another to descend into nan mantle (SN: 1/13/21).
At nan apical of nan crater, Perseverance traveled done an area known arsenic nan Pico Turquino Hills, wherever it captured images of galore outcrops. “What we recovered successful these comparatively mini outcrops is that nan rocks are highly diverse, and it appears that each 1 of nan hills that dress up nan Pico Turquino Hills person a chopped assemblage of mostly igneous minerals, pinch immoderate alteration by water,” Farley said. “These are apt pieces of nan earliest crust of Mars.”
Instruments aboard Perseverance cannot precisely day nan rocks. Instead, researchers are basing their property estimates connected their existent knowing of nan crater’s statement and Mars’ history. “They are our champion estimates, but they are conscionable estimates,” Farley said. “This is 1 of nan reasons why we want to do sample return.”
If nan recently encountered Martian rocks are really that old, they could incorporate accusation astir how rocky planets for illustration Mars and Earth evolved successful their infancy (SN: 3/16/17). “For america to understand really rocky planets behave successful that first, say, half a cardinal years, [we] can’t do it from Earth,” Farley said.
A caller imaginable mounting for Martian life
Ancient rocks weren’t each that Perseverance recovered successful nan Pico Turquino Hills. The rover besides came crossed grounds of a wholly caller habitable mounting for imaginable Martian life (SN: 7/15/24): a section of “brilliant white, cantaloupe-sized [stones], and nan instruments aboard nan rover corroborate that these cobbles are axenic quartz,” Farley said. “This has ne'er been seen before” connected Mars.
Quartz forms successful places wherever basking fluids move done rocks, and sometimes astatine temperatures that are habitable. These rocks whitethorn person formed successful a mounting akin to a basking spring, and we cognize those environments tin support life connected Earth, truthful possibly thing akin erstwhile existed connected Mars, Farley said. “This is simply a perchance habitable situation that’s wholly different from nan habitable environments that Perseverance investigated connected nan crater floor.”
According to Farley, nan extremity is to now hunt for quartz wherever it is still embedded successful nan Martian surface, truthful it tin beryllium sampled. “Neither our drill nor our abrader tin really run connected specified loose, [cobblestone-sized rocks],” Farley said. “The stone would conscionable move retired of nan measurement if we effort to activity connected it.” Finding easier-to-access quartz could besides thief researchers amended understand really nan mineral fits into nan remainder of nan Martian stone record.
Next stop, Witch Hazel Hill
Moving connected from nan Pico Turquino Hills, Perseverance will walk nan adjacent six months exploring an area called Witch Hazel Hill. Located distant from nan crater, nan rocks astatine Witch Hazel Hill should beryllium much typical of nan earth science of nan broader region beyond, said planetary intelligence and geologist Candice Bedford of Purdue University successful West Lafayette, Ind., astatine nan news briefing.
What’s more, NASA’s Mars orbiters person already identified extended outcropping of layered rocks astatine Witch Hazel Hill. “As geologists we emotion layered outcrops,” Bedford said. “For us, each furniture preserved is like, arsenic we look down done that, it’s for illustration turning a [page successful nan book] of Martian history.”