Name: Signs of Life on Mars? NASA's Discovery, Explained
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Billions of years ago, Mars’ Jezero Crater held a lake fed by rivers that could have carried minerals and maybe even organic matter. On Earth, places like that are teeming with microbial life.

NASA’s Perseverance rover may have found the clearest signs of ancient life on Mars yet.

Billions of years ago, Mars’ Jezero Crater held a lake fed by rivers that could have carried minerals and maybe even organic matter. On Earth, places like that are teeming with microbial life.

Signs of Life on Mars? NASA's Discovery, Explained

NASA’s Perseverance rover may have found the clearest signs of ancient life on Mars yet.

Space & Flight

Signs of Life on Mars? NASA's Discovery, ExplainedPublished: September 23, 2025NARRATOR: This speckled rock could be evidence of ancient life on Mars. NASA called it,SEAN DUFFY: The clearest sign of life that we have ever found.NARRATOR: Scientists say that traces of minerals here could have been left behind by ancient microbial life, maybe after a meal, about three and a half billion years ago, a time when primitive life was thriving on Earth.Using tools on the Perseverance Mars Rover, scientists were able to analyze the chemical makeup of the rock. These teeny tiny dark specks, NASA are calling them poppy seeds, contain vivianite, an iron phosphate mineral. And these areas, nicknamed leopard spots, have vivianite in the dark ring, but in the center contain greigite, an iron sulfide mineral.The rock itself is also rich in organic carbon, sulfur, oxidized iron, which is rust, and phosphorus. And the combination of these could have been a rich energy source for microbes. But there is a possibility the minerals in this martian rock were created by non-living sources.To know for sure, NASA will have to rule out all other geological and chemical processes. And to do that, researchers hope to one day bring the samples from Mars to Earth to study them more closely.So far, the Perseverance Rover has collected more than 20 rock samples from the red planet. Further analysis here on Earth could bring us closer to answering one of the most fundamental questions for humanity: are we alone?Believe it or not, Mars was not always the cold inhospitable desert it is today. Several billion years ago, there were flowing rivers and lakes, and even an atmosphere, but over time, that atmosphere was lost, transforming the climate and the red planet's ability to sustain life on its surface.But this area in the northern hemisphere of Mars, called Jezero Crater, has the tell-tale geographic signs of water, fan-shaped deltas. Scientists think rivers once spilled over the crater wall and created a lake. Billions of years ago, active rivers could have deposited minerals and organic molecules here. If Mars ever hosted microbial life, this was the place to look.In 2021, the Perseverance Mars Rover landed in Jezero crater. This crater has some of the oldest rocks in the solar system. And in 2024, the rover found this speckled rock in an ancient river valley called Neretva Vallis in an area known as the Bright Angel Rock formation. But notably, this rock outcrop is younger than most of the other samples the rover has taken, possibly suggesting that the conditions for life could have lasted longer than we thought.Since then, scientists have been trying to understand more about this area of Jezero Crater, and rule out all the possible origins of these minerals. It's possible these minerals did not come from microbes, but researchers haven't been able to find any evidence of that yet. The rock doesn't show signs of extreme heat or acidity that could have been responsible for the compounds.Past missions have found hints of life before, like methane spikes or hints of organic molecules. But the standard of proof for a major discovery like this, life on another planet, is high. NASA actually has a scale to assess confidence. The CoLD scale, which stands for "Confidence of Life Detection," and this discovery sits at about a two out of seven.So has Perseverance definitely found life on Mars? No, not yet. But this discovery is one of the strongest clues so far. Bits of chemistry and context that supports habitability. It doesn't settle the question, but it pushes us one step closer, reminding us that the story of life on Mars isn't totally fictional. It may be written in stone.

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Signs of Life on Mars? NASA's Discovery, Explained

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Support Provided By

Explore More

Could Mars Have a Ring Around It One Day?

Ultimate Mars Challenge

The Planets: Mars