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NASA announces “groundbreaking discovery” of life on Mars
A recent analysis of the Sapphire Canyon mudstone core, drilled by NASA’s Perseverance rover in July 2024, adds new and convincing evidence to the ongoing search for life on Mars.
The study describes minerals and textures that – on Earth – are often linked to microbial activity. At the same time, the authors stress that some unknown, nonbiological chemistry could also explain the signals.
“This finding by Perseverance is the closest we have ever come to discovering life on Mars. The identification of a potential biosignature on the Red Planet is a groundbreaking discovery, and one that will advance our understanding of Mars,” said acting NASA Administrator Sean Duffy.
“NASA’s commitment to conducting Gold Standard Science will continue as we pursue our goal of putting American boots on Mars’ rocky soil.”
The core was taken from a rock named “Chevaya Falls” in Neretva Vallis, an ancient river channel about a quarter mile wide that once fed Jezero Crater’s lake.
After drilling, Perseverance sealed the sample for possible return to Earth, where laboratory instruments can perform tests far beyond the rover’s onboard capabilities.
Inside the Martian mudstone
Lead author Joel A. Hurowitz of Stony Brook University (SBU) reports a fine-grained mudstone with circular reaction fronts informally called leopard spots, plus small nodules embedded in layered sediments.
Perseverance’s SHERLOC and PIXL instruments mapped organic carbon with phosphate, iron, and sulfur arranged in distinct, repeating patterns.
Two minerals stand out: vivianite and greigite. Vivianite is an iron phosphate, while greigite is an iron sulfide associated with iron and sulfur cycling in oxygen-poor settings.
These features show up in rocks that settled from water, not in lavas. The site on Mars lies along Bright Angel, a set of outcrops that preserve layers and veins consistent with slow changes after the mud was laid down.
Textures and chemistry point to low temperature reactions that reorganized elements already present in the mud.
That detail matters because low temperatures fit environments that life can handle, while very hot conditions tend to erase delicate signals.
Earth microbes leave similar traces
On Earth, vivianite often forms where microbes reduce iron in water-rich sediments and trap phosphorus in blue-green nodules.
Laboratory and field work document biologically mediated vivianite through extracellular electron transfer.
Greigite frequently appears where sulfate reducing bacteria drive chemistry in anoxic muds. In controlled experiments, greigite was detected only in live biotic setups after months of incubation.
The Martian rock shows rims rich in vivianite surrounding small cores enriched in greigite. That bullseye pattern matches a sequence of electron transfer reactions seen in some Earth sediments.
None of this proves metabolism happened in Bright Angel mud, but it shows the chemistry is right for it. That is a subtle point, and it is the reason scientists keep the language cautious.
Evidence of life on Mars
A potential biosignature is a feature that might have a biological origin but still needs more data to rule out nonbiological sources.
NASA points mission teams and the public to the Confidence of Life Detection, or CoLD scale, which encourages staged claims and independent checks.
The CoLD mindset is simple in practice. First detect a signal, then exclude contamination, then tackle alternatives, and only then talk about life on Mars with high confidence.
The Bright Angel work sits early on that ladder. It clears several necessary steps but leaves demanding tests for the lab.
Organic compounds can also arrive by meteorites or form without biology. The authors note those routes and describe how future analyses could tell paths apart.
Organic signals, but no certainty
The Mars rover detected organic carbon in several targets within Bright Angel. Reaction fronts rimmed with vivianite surround cores richer in greigite, a pairing consistent with iron and sulfur cycling recorded in the paper.
Mineral veins include calcium sulfate, while the mudstone remains fine-grained and low in magnesium and manganese. There is no sign of intense heating that would reset the rock or scramble tiny textures.
The outcrop sits within layered sediments deposited by water flowing through Neretva Vallis. That channel spans roughly a quarter mile across, which implies sustained flow into Jezero’s ancient lake.
Low temperature context favors life-compatible chemistry, but it does not require life. Abiotic organics and mineral reactions can sometimes copy the same shapes and signals.
Not proof, but potential life on Mars
“It’s not life itself,” said Nicky Fox, associate administrator for NASA’s Science Mission Directorate, stressing that this is a potential biosignature, not proof of life. The lead author echoed that caution.
“We cannot claim this is more than a potential biosignature,” said Hurowitz. Other officials also underscored the stakes and the limits.
“[But] this very well could be the clearest sign of life that we’ve ever found on Mars,” said Sean Duffy, acting NASA administrator.
Caution is not hedging for its own sake. It is how science avoids false alarms when the question is this important.
Implications for habitability
If the vivianite and greigite formed through microbe-like metabolisms, then Bright Angel captures a period when surface waters supported the same chemical strategies some cells use for energy today.
That would extend Mars’s habitability into a window when this part of Jezero was still wet.
If abiotic paths made the same pattern, the rock still records redox organization of iron, sulfur, and phosphorus in Martian mud. That is a window into how the planet cycles key elements without biology.
Either outcome matters for the bigger story. Mars did not just dry out, it changed its chemistry over time, and these samples let researchers track that change layer by layer.
The work also flags what to measure next. Isotopes, microtextures, and the exact structure of carbon in the core can separate metabolic signatures from chemical lookalikes.
Search for life on Mars moves forward
The authors lay out lab experiments and field analogs on Earth to test whether nonbiological reactions can reproduce these textures and mineral pairings.
They also point to analyses that require the sample in a clean Earth lab, including isotope ratios that biology tends to skew.
Sample return planning will shape how fast those tests happen. Meanwhile, the rover can keep mapping where these features cluster and how they relate to other rock units nearby.
PIXL and SHERLOC have shown enough sensitivity to guide that search. The pairing of elemental maps and Raman detections gives a consistent picture that can be applied to other outcrops.
As new targets are logged, the CoLD framework will help communicate progress without getting ahead of the data. That is how a potential biosignature becomes a result people can trust.
The study is published in the journal Nature.
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Barbra Streisand among stars to pay tribute to Robert Redford: ‘One of the finest actors ever’ | Robert Redford
Barbra Streisand has paid tribute to Robert Redford, calling him “one of the finest actors ever”.
The entertainer shared a statement after her co-star in The Way We Were died at the age of 89 on Tuesday. His publicist wrote that he died “at Sundance in the mountains of Utah – the place he loved, surrounded by those he loved”.
On Instagram, Streisand reminisced about their time together while making the 1973 hit.
“Every day on the set of The Way We Were was exciting, intense and pure joy,” she wrote. “We were such opposites: he was from the world of horses; I was allergic to them! Yet, we kept trying to find out more about each other, just like the characters in the movie. Bob was charismatic, intelligent, intense, always interesting— and one of the finest actors ever. The last time I saw him, when he came to lunch, we discussed art and decided to send each other our first drawings. He was one of a kind and I’m so grateful to have had the opportunity to work with him.”
Romantic drama The Way We Were was a critical and commercial hit with Streisand’s theme song also becoming a chart hit and receiving an Oscar nomination.
Streisand’s tribute joins a long list from Hollywood and beyond after Redford’s death. Meryl Streep, who starred with him in Out of Africa and Lions for Lambs, wrote: “One of the lions has passed. Rest in peace my lovely friend.”
Jane Fonda, who starred with him in four movies including Barefoot in the Park, said in a statement: “It hit me hard this morning when I read that Bob was gone. I can’t stop crying. He meant a lot to me and was a beautiful person in every way. He stood for an America we have to keep fighting for.”
“Bob was a unique artist, in front of and behind the camera … and he gave the world of American cinema something irreplaceable and lasting with Sundance,” said film-maker Martin Scorsese, who Redford directed in his film Quiz Show. “It saddens me to know that I won’t be seeing him again. And I’ll never forget my time with him.”
Ethan Hawke remembered him as “our ultimate champion of independent film, relentless advocate for authentic storytelling and fiercely passionate environmentalist”, while Leonardo DiCaprio told Associated Press that Redford’s death was “a huge loss”.
“Not only was he an incredible actor — we all know his work — but his ability, as a director too, films like Quiz Show,” he said. “He was one of the first guys to do political thrillers – Three Days of the Condor, All the President’s Men … he paved the way for films like this but more so than anything, he was a staunch environmental leader and was a member of the NRDC, like me, and fought for Indigenous rights — the list goes on and on. We lost a legend today.”
Morgan Freeman wrote on Instagram: “There are certain people you know that you’re going to click with. After working with Robert Redford on Brubaker in 1980, we instantly became friends. Working with him again in An Unfinished Life was a dream come true. Rest peacefully, my friend.”
Journalist Bob Woodward, who Redford played in All the President’s Men, wrote on Instagram, “He will be remembered as one of the greatest storytellers in our country’s history. He elevated stories beyond mainstream. He not only cared about the environment, but he took all conceivable actions to protect it.”
Samuel L Jackson wrote on Instagram: “It was a dream come true to work on screen with Mr Redford. Sometimes your heroes don’t disappoint and truly are as great as you imagined.”
Hillary Clinton shared a picture of her with Redford, writing: “He championed progressive values like protecting the environment and access to the arts while creating opportunities for new generations of activists and filmmakers. A true American icon.”
Scarlett Johansson, who starred in The Horse Whisperer, a drama directed by and starring Redford looked back on their time together. “He was patient and warm and kind,” she said. “Bob taught me what acting could be, and it was from his generosity and patience that I was inspired to pursue the possibilities of the craft. That same generosity and love of the art inspired Bob’s creation of Sundance, a place where film-makers learn from one another, inspire one another, and discover one another’s talent. Bob, thank you for your belief in me and for your grace and guidance.”
He was also described by Ron Howard as an “artistic game changer”.
Redford was known for his many films as an actor, including The Sting, All the President’s Men and Spy Game, but also played a key role in the Sundance film festival, with many seeing him as a pioneer of US independent cinema.
“We are deeply saddened by the loss of our founder and friend Robert Redford,” a Sundance statement read. “Bob’s vision of a space and a platform for independent voices launched a movement that, over four decades later, has inspired generations of artists and redefined cinema in the US and around the world.”
KANSAS CITY, Mo. — Cal Raleigh broke Mickey Mantle’s record for homers by a switch-hitter and tied the Mariners record set by Ken Griffey Jr. when the Seattle star hit his 55th and 56th of the season in consecutive at-bats against the Royals on Tuesday night.
Raleigh doubled in his first at-bat on a hot, humid night in Kansas City. He came up again in the third inning and, batting left-handed against Michael Wacha, fouled off a changeup and took a sinker for a ball before Raleigh sent a hanging curveball 419 feet over the right-field fence for his 55th home run of the season.
That broke the switch-hitter mark set by the Yankees star in 1961, which Raleigh had tied against the Angels on Sunday.
BIG DUMPER TWO HOME RUN NIGHT!
Cal Raleigh ties Ken Griffey Jr. for the most home runs in a single season in franchise history 😳
(via @MLB) pic.twitter.com/Wpz7lk7W4n
— ESPN (@espn) September 17, 2025
The All-Star catcher was back up in the fourth inning Tuesday night. This time, batting right-handed against left-hander Daniel Lynch IV, Raleigh sent the first pitch he saw 425 feet to straightaway center for his 56th homer.
Griffey set the Mariners record when he hit 56 homers during the 1997 season and matched the mark the following year.
After both home runs, Raleigh got a standing ovation from a small group of Mariners fans behind the visiting dugout at Kauffman Stadium. Many Royals fans, who had turned out to watch a club fading from playoff contention, also applauded the home runs. It was Raleigh’s 20th career multihomer game and his 10th this season, the most in a single season by a catcher in MLB history.
There have only been nine 60-homer seasons in the majors. Aaron Judge had the last when he hit 62 for the Yankees in 2022, an American League record. Raleigh would need to hit six more home runs over the next 11 games to tie Judge’s record.
The Associated Press and ESPN Research contributed to this report.
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Alleged Charlie Kirk assassin Tyler Robinson charged with murder; prosecutors to seek death penalty
Read the chilling text exchange between Charlie Kirk’s alleged assassin and his trans lover
Tyler Robinson’s roommate, Lance Twiggs, a biological male that identified as transgender who was in a romantic relationship with Robinson, provided evidence including a series of text messages from Robinson on September 10, 2025.
Prosecutors say Twiggs received a text message from Robinson which said, “drop what you are doing, look under my keyboard.”
Twiggs looked under the keyboard and found a note that stated, “I had the opportunity to take out Charlie Kirk and I’m going to take it.”
Police found a photograph of this note. Prosecutors say the following text exchange then took place: After reading the note, Twiggs responded, “What?????????????? You’re joking, right????”
Robinson: I am still ok my love, but am stuck in orem for a little while longer yet. Shouldn’t be long until I can come home, but I gotta grab my rifle still. To be honest I had hoped to keep this secret till I died of old age. I am sorry to involve you.
Roommate: you weren’t the one who did it right????
Robinson: I am, I’m sorry.
Roommate: I thought they caught the person?
Robinson: no, they grabbed some crazy old dude, then interrogated someone in similar clothing. I had planned to grab my rifle from my drop point shortly after, but most of that side of town got locked down. Its quiet, almost enough to get out, but theres one vehicle lingering.
Roommate: Why?
Robinson: Why did I do it?
Roommate: Yeah.
Robinson: I had enough of his hatred. Some hate can’t be negotiated out. If I am able to grab my rifle
unseen, I will have left no evidence. Going to attempt to retrieve it again, hopefully they have moved on. I haven’t seen anything about them finding it.
Roommate: How long have you been planning this?
Robinson: a bit over a week I believe. I can get close to it but there is a squad car parked right by it. I think they already swept that spot, but I don’t wanna chance it.
Robinson: I’m wishing I had circled back and grabbed it as soon as I got to my vehicle. … I’m worried what my old man would do if I didn’t bring back grandpas rifle … idek if it had a serial number, but it wouldn’t trace to me. I worry about prints I had to leave it in a bush where I changed outfits. didn’t have the ability or time to bring it with. … I might have to abandon it and hope they don’t find prints. how the f–k will I explain losing it to my old man. … only thing I left was the rifle wrapped in a towel. … remember how I was engraving bullets? The f–kin messages are mostly a big meme, if I see “notices bulge uwu” on Fox New I might have a stroke alright im gonna have to leave it, that really f–king sucks…judging from today I’d say grandpas gun does just fine idk. I think that was a $2k scope.
Robinson: delete this exchange.
Robinson: my dad wants photos of t
he rifle … he says grandpa wants to know who has what, the feds released a photo of the rifle, and it is very unique. Hes calling me rn, not answering. …
Robinson: since trump got into office [my dad] has been pretty diehard maga. …
Robinson: Im gonna turn myself in willingly, one of my neighbors here is a deputy for the sheriff.
Robinson: you are all I worry about love.
Roommate: I’m much more worried about you.
Robinson: don’t talk to the media please. don’t take any interviews or make any comments. … if any police ask you questions ask for a lawyer and stay silent
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