Less than two weeks ago, NASA scientists announced a potential biosignature in a Martian rock called Sapphire Canyon. Now, a new study shows that similar life-friendly conditions were widespread throughout Jezero Crater, where the Perseverance rover is operating. This broadens the search area for ancient life on the Red Planet. The results were published on September 11, 2025, in the Journal of Geophysical Research: Planets.

Potential Biosignature in Sapphire Canyon

In July 2024, Perseverance discovered “leopard spots” on the reddish Cheyava Falls rock in Jezero Crater. Analysis revealed signs that may indicate microbial life: organic compounds, minerals, and textures characteristic of biological processes. The rock, dated to 3.2–3.8 billion years ago, was taken from an ancient riverbed where water once flowed.

“This is the strongest evidence yet for the possibility of ancient life on Mars, but not definitive proof,” scientists noted. Non-biological processes, such as mineral reactions under heating, can also create similar features. Laboratory tests on Earth are needed for confirmation.

Jezero’s Minerals: Three Eras of Water

The new study, based on three years of Perseverance data, identified 24 minerals that reveal the crater’s history. Minerals are “storytellers,” forming under specific temperatures, pH, and chemical conditions. They outline three stages of water interaction with Jezero’s volcanic rocks:

  1. Hot, acidic conditions: minerals such as greenalite, gysingite, and ferroaluminoceladonite point to early hot fluids. These were the least favorable for life — high temperatures and low pH damage biological structures.
  2. Neutral waters: minerals like minnesotaite and clinoptilolite suggest cooler, neutral waters — better for microbes, as seen in Earth analogs.
  3. Alkaline, low-temperature conditions: widespread sepiolite indicates alkaline waters — ideal for life, similar to conditions on Titan. This implies a broad habitable zone within the crater.

“Jezero experienced multiple episodes of water activity, each of which could have supported life,” said lead author Eleanor Moreland of Rice University.

How Was the Data Collected?

Perseverance, which landed in Jezero in February 2021, gathered data using PIXL (an X-ray spectrometer) and the MIST algorithm. MIST analyzes minerals while accounting for instrument error, using thousands of simulations — much like meteorologists model hurricanes. This created a “mineralogical archive” of the crater, confirming the volcanic origin of the rocks and their interaction with water.

The study did not directly analyze Sapphire Canyon but showed that the conditions at Cheyava Falls (where the sample was taken) were typical of Jezero. “This broadens the stage for searching for life,” the scientists said.

Context: Biosignatures and Sample Return

The discovery in Sapphire Canyon is part of Perseverance’s mission to collect 27 samples for eventual return to Earth. The rover sealed them in tubes, including the Sapphire Canyon sample from Bright Angel (an ancient river delta). Laboratory tests on Earth are key: only they can confirm whether the signs are biological or non-biological.

“We’re at the limit of what a rover can do on the surface,” said Katie Stack Morgan, Perseverance’s deputy project scientist. “The samples are meant for analysis on Earth.”

However, the Mars Sample Return (MSR) program is under threat: in January 2025, NASA announced a search for cheaper alternatives due to budget overruns. The return is currently scheduled for 2035, but it may be canceled in 2026. Acting NASA administrator Sean Duffy said: “We believe there is a better, faster way to bring the samples back.”

Meanwhile, China’s Tianwen-3 mission plans to collect 500 grams of Martian samples by 2028 and return them in 2031, potentially overtaking NASA.

Significance for Science

Jezero’s minerals show how water shaped Mars — from volcanic lava to lakes and deltas. This confirms that the crater was habitable 3–4 billion years ago. The MIST algorithm will help select samples for return, prioritizing the most valuable ones.

“The minerals point to a transition from harsh conditions to more favorable ones. Life could have existed in alkaline waters,” noted co-author Kirsten Siebach.

In Short…

Perseverance has found signs of habitability in Jezero: three stages of water activity, from acidic fluids to alkaline lakes. This provides context for the potential biosignature in Sapphire Canyon — a possible trace of ancient life. The samples await return, but MSR is in jeopardy, while China is moving ahead. The discovery is a reminder: Mars may once have been home to microbes, and the answers lie in the Red Planet’s soil.