NASA's Perseverance finds bleached rocks on Mars, hinting at ancient water

• Scientists believe these rocks were formed by ancient rainfall, similar to how they form in tropical climates on Earth.
• The discovery adds to the evidence that Mars may have once been a habitable planet capable of supporting life.
• Perseverance is one of two rovers exploring the Martian surface for signs of past life and collecting rock samples.

More evidence that Mars was once a habitable, wet oasis not dissimilar to Earth has been found in the rocks scattered throughout the red planet.

The rocks, bleached white from what scientists suspect was ancient rainfall and humidity on Mars, were happened upon by NASA's Perseverance rover. The car-sized robot is one of two rovers that have spent years scouring the surface of our planetary neighbor searching for any sign that Mars was ever home to life.

A team of researchers who analyzed the thousands of rocks say their findings, published in December in the journal Communications Earth & Environment, serve as the latest evidence that the rust-hued Martian landscape could once have supported life.

What's more, the rocky fragments could hold clues into how Mars developed into its barren, rocky state, said study lead author Adrian Broz, a planetary scientist at Purdue University.

“Elsewhere on Mars, rocks like these are probably some of the most important outcrops we’ve seen from orbit because they are just so hard to form,” Horgan, a long-term planner on NASA’s Perseverance mission, said in a statement. “You need so much water that we think these could be evidence of an ancient warmer and wetter climate where there was rain falling for millions of years.”

Here's everything to know about Perseverance, and the latest significant finding from the rover's adventures:

What is NASA's Perseverance rover on Mars?

NASA's Perseverance rover, along with Curiosity, is one of the agency's two car-sized robots exploring the Martian surface for signs that the planet was once habitable.

Scientists believe the geology of Mars may hold valuable clues about ancient life, and so the robotic vehicles, controlled remotely from Earth, have slowly navigated the rocky terrain to scoop up and collect intriguing samples.

After launching in 2020, Perseverance made a 200-day, 300-million-mile journey to reach Mars' Jezero Crater in February 2021. At the end of 2024, after years in the trenches of Jezero, Perseverance summited the steep Martian crater to begin the next leg of its journey exploring the rim.

Perseverance discovers bleached rocks on red planet

The bleached rocks discovered by the Perseverance rover, analyzed in the recent study, are white, clay-rich kaolinite fragments that are commonly found on Earth. Scientists suspect kaolinite rocks, also rich in aluminum, are formed from millions of years of being leached of all other minerals in tropical, rainy climates.

The Martian samples the scientists studied, which bore a strong match to rocks found near San Diego and South Africa, ranged from as small as a pebble to as large as a boulder.

"It tells us that there was once a lot more water than there is today,” Broz said in a statement.

Because no major outcropping is near where the samples were found, it's possible they were washed into the Jezero Crater – once believed to have been a large lake filled with water – or were thrown in and scattered by an impact, according to the researchers. Satellite imagery has also spotted large outcroppings of kaolinite in other areas of Mars.

Could there have been life on Mars?

The study authors argue that the discovered rocks serve as something of a Martian time capsule, concealing information from billions of years ago about the conditions that formed the now-barren planet.

After all, where there's water, there usually is life.

It's not so far-fetched to imagine that some sort of lifeforms once populated Mars – it's a major reason why NASA has sent a fleet of both ground and orbital vehicles to scour the Red Planet for years. In fact, it was none other than Perseverance that was behind the discovery revealed in September 2025 of a rocky sample that scientists determined could possibly preserve evidence of ancient microbial life.

“All life uses water,” Broz said in his statement. “So when we think about the possibility of these rocks on Mars representing a rainfall-driven environment, that is a really incredible, habitable place where life could have thrived if it were ever on Mars.”

Eric Lagatta is the Space Connect reporter for the USA TODAY Network. Reach him at [email protected]