An international team of researchers has demonstrated a new biosignature detection method for distinguishing between abiotic and biotic apatite mineral samples on Mars using instruments already aboard the Perseverance Rover, rather than returning samples to Earth.

The team said their mineral-based biosignature detection approach was successful in identifying samples with nearly 98% accuracy and allows for “deeper time” searches for signs of life, given the longer-lasting nature of minerals compared to biological materials. They also suggest their approach could broaden the capabilities of upcoming rover and life-hunting missions without adding new tools or sensors.

Advantages of a Mineral-Based Approach for Hunting Biosignatures

In a study detailing the team’s technique, Robert M. Hazen from the Carnegie Institution for Science and colleagues explained that searching for life and biosignatures beyond Earth “is a central objective of astrobiology.” They also note that this research is complemented by studies exploring the origin and early evolution of terrestrial life. Still, they add, although identifying biosignatures remains a key challenge, “robust mineral biosignatures remain limited.”

For example, most proposed biosignature missions focus on organic molecules or searching for fossils preserved in sedimentary environments or aquatic environments, including the subsurface oceans of some of the solar system’s moons. However, there are few, if any, proposed missions searching for signs of life preserved in mineral records, which the team notes “can retain records of biological activity over much longer geological timescales”

On Mars, NASA’s Perseverance rover has meticulously collected soil and rock samples deemed most likely to contain biosignatures. However, efforts to send a future sample-return mission to the red planet to retrieve samples are currently stalled and may never be completed.

According to the study authors, there are flight-ready instruments “already deployed on the “Perseverance” rover and planned for deployment on the “Rosalind Franklin” rover capable of searching for signs of life in place rather than returning the samples to labs on Earth. However, they add, “to fully exploit these mission-limited yet information-rich tools, it is essential to efficiently extract as much diagnostic value as possible from the data they generate.”

To search for mineral-based biosignatures, the team focused its research on Raman spectroscopy.

Using Instruments Already Aboard Mars Rovers to Search for Life

“Raman spectroscopy is particularly attractive because it provides bond-specific information on crystal structure and chemical substitution in a nondestructive manner,” they explain.

The team also notes that the Raman spectra acquired by the rover’s instruments “are highly comparable to those obtained under laboratory conditions,” increasing the robustness of any possible life signal.

“This consistency enables direct translation of laboratory reference datasets to planetary environments,” they write.

However, they add, Raman spectra from natural geological samples are often complex, including “overlapping vibrational modes, heterogeneous backgrounds, and chemistry-dependent band shifts.” Until now, this complexity has made interpreting samples based on individual spectral peaks or qualitative inspection inherently challenging.

“Identifying reliable biosignatures that can be detected by flight-ready instruments, such as Raman spectroscopy, remains a central challenge in astrobiology,” the researchers explain. “Developing robust mineralogical indicators of life therefore represents a critical and complementary approach for planetary exploration.”

Approach Distinguishes Abiotic and Biotic Features

To test their approach, the team focused on the mineral apatite. A ubiquitous phosphate, the team notes that apatite can be found “in terrestrial and extraterrestrial environments.” Although apatite is a major component of biological formations such as teeth and bones, it also forms naturally, providing an opportunity to search for biosignatures over much longer timescales if scientists can differentiate the two.

“Here, we integrate Raman spectroscopy with interpretable machine learning to distinguish biotic from abiotic apatite, a ubiquitous phosphate mineral in terrestrial and extraterrestrial environments,” the researchers write.

First, Hazen and colleagues compiled 331 Raman spectra samples. Critically, they included only specimens with known origin attributes: biogenic, abiogenic, or synthetic.

Next, they used this data to extract 21 “band-resolved features.” This was accomplished by training a random forest classifier to identify the “most diagnostic” features of each sample.

“Determining the origin of a sample involves assessing multiple independently varying features of a Raman spectrum, including band positions, widths, and relative intensities, the type of multivariate analysis well suited to machine learning,” the study authors explain.

After some comparative analysis, the team ultimately determined that a sample’s carbonate band and the width of the dominant phosphate band, “reflecting chemical composition and crystal structure, respectively,” were the strongest indicators of biological, natural, or synthetic origin.

After using their method to check the 311 samples, the team said the model successfully  distinguished biotic from abiotic apatite “with classification accuracy exceeding 96%.” In fact, the team reported that their mineral-based biosignature detection method misidentified only one biotic apatite sample as abiotic and one abiotic sample as biological.

“Here, we show that biologically formed apatite can be distinguished from abiotic counterparts using interpretable machine learning applied to Raman spectra,” the study authors write.

Life Detection Across Diverse Planetary Environments

When discussing the potential implications of their new mineral-based biosignature detection approach, the team noted that their findings establish a “broadly applicable and mission-relevant strategy for deep-time archives and future planetary missions.” More broadly, the researchers note that their findings highlight the “growing importance of combining flight-ready analytical instruments with AI” to fully leverage datasets already captured by Mars rovers and other “in situ” planetary missions.

“As planetary exploration increasingly shifts toward autonomous decision-making and target selection, the integration of interpretable AI with mineralogical biosignatures offers a powerful and extensible framework,” they write.

Beyond mineral-based biosignature detection strategies, the research team notes that future life hunting missions will “increasingly rely on the joint interpretation of mineralogical and organic spectroscopic signatures.” These include on-board py-GC-MS measurements, infrared spectroscopy, luminescence, laser-induced breakdown spectroscopy, X-ray fluorescence, and “other analytic methods.”

Future approaches will increasingly rely on AI to analyze these disparate datasets, which the authors note will allow for biologically mediated patterns to be distinguished from natural or synthetic backgrounds “in a physically and chemically consistent manner.”

“In this context, such an integrative and interpretable framework provides a pathway toward autonomous, mechanism-informed life detection across diverse planetary environments, advancing the broader goals of planetary science in understanding habitability, biosignature preservation, and the coevolution of geology and biology,” the authors conclude.

The study “Mineral biosignature identification from Raman spectroscopy using machine learning” was published in PNAS Nexus. 

Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.

A new NASA orbital image captures Perseverance after completing a marathon across the surface of Mars. NASA’s Perseverance rover has completed the equivalent of a full marathon on Mars, reaching 26.2 miles (42.195 kilometers) after five years and four months of driving across the Red Planet. The milestone came on the 1,890th Martian day, or [...]

A tiny green dot appearing in an image taken by NASA’s Mars Reconnaissance Orbiter (MRO) captures a historic tale of Red Planet exploration by one of its first Earthling visitors.

That visitor—a robotic rover named Perseverance—has been conducting investigations on Mars since February 18, 2021, and the new aerial images reveal its current location in an area that mission specialists have dubbed “Arbot.”

While Perseverance’s latest appearance reveals little more than a greenish spec on the planet’s rust-colored surface, also visible in the new images are the long path its formidable tires have left in the Martian soil as the robotic explorer has trekked west of its initial landing site.

The new images, captured on June 13, 2026, were taken just one day before Perseverance broke the previous distance record held by a robotic explorer on Mars: NASA’s Opportunity rover.

However, Perseverance completed this phase of its journey in record time compared to its predecessor, which took more than 11 years to traverse a similar distance. Perseverance, by contrast, covered the same distance in less than half that time, with just five years and four months of travel now behind it.

The images were made possible by the MROs’ High-Resolution Imaging Science Experiment (HiRISE) camera, which also captured surface features in the Arbot area that include ridges and windswept areas along Mars’ rugged exterior.

Built and operated by the University of Arizona, HiRISE captures images with resolutions as fine as about 25 centimeters (10 inches) per pixel, allowing researchers to distinguish features roughly the size of a kitchen table from orbit. The camera has returned hundreds of thousands of detailed images since the MRO arrived at Mars two decades ago, contributing to a growing data set that has transformed scientists’ understanding of the Red Planet.

Documenting everything from active dust avalanches and shifting dunes to fresh impact craters, the unprecedented resolution its imagery provides has made HiRISE one of the most powerful planetary imaging instruments ever deployed.

Last year, the MRO’s HiRISE camera also successfully captured images of the interstellar comet 3I/ATLAS as it made its way past Mars during its trip through our Solar System. Although the HiRISE images weren’t the clearest images of the interstellar visitor obtained during its visit, they did help demonstrate just how formidable NASA’s MRO and its suite of instruments are.

Additional details about Perseverance and its mission can be found at NASA’s official web page, and information about the MRO can be found here.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.

Evidence for possible life on Mars in the ancient past continues to build, thanks to a recent discovery by NASA’s Perseverance rover that identified complex carbon in two mudstones.

As detailed in a recent paper published in Science Advances, Perseverance collected samples in the Jezero crater, a location that has continued to yield possible biosignatures of life on Mars in the ancient past.

In the same region, scientists reported potential evidence of microbial activity on ancient Mars, adding to a growing list of circumstantial evidence for one of the most intriguing possibilities in modern space exploration: the prospect that Earth may not have been the only planet in our Solar System that has held the potential to host life.

A Prime Location for Life on Mars

Among the study’s most significant findings is that complex macromolecular carbon was discovered alongside other potential biosignatures. Jezero Crater, a 28-mile-wide impact basin on the Martian surface, once contained flowing water roughly 3.5 billion years ago, making it one of the most promising locations in the search for ancient life. Water is essential to all known life on Earth, serving as a universal solvent and playing a critical role in biological processes.

“Jezero Crater was selected as a landing site due, in part, to its past evidence of aqueous activity and potential to preserve organic material,” co-lead author Kyle Uckert, a research scientist at NASA’s Jet Propulsion Laboratory, told The Debrief. “The Perseverance Rover’s exploration of Jezero Crater helps us understand the past habitability of Mars.”

Perseverance targeted a distinctive geological feature known as the Bright Angel outcrop, where the samples were collected. The outcrop consists of mudstones deposited in the dry bed of an ancient river that once flowed into Jezero Crater. Comparable sedimentary deposits on Earth are often associated with environments capable of preserving evidence of microbial life.

Analyzing Samples

Determining the origin of the organic carbon preserved within these Martian rocks is key to understanding whether the Red Planet ever supported life.

Using its onboard Raman spectrometer, Perseverance mapped the distribution of the rocks’ organic matter. One sample contained organic carbon within a primary silicate-dominated matrix, while another preserved carbon within secondary carbonate and sulfate minerals.

Notably, the carbon appears to have remained remarkably well preserved despite billions of years of exposure to the harsh Martian environment. Researchers suggest its limited weathering may indicate that the material is resistant to radiation and oxidation—possibly because it is mixed with iron-rich regolith or protected by clay minerals—or that it was only recently exposed at the surface through erosion.

The researchers are quick to point out that their findings do not determine whether the carbon originated through biological or non-biological processes. Nevertheless, the discovery adds another intriguing piece of evidence to the ongoing search for ancient life on Mars.

“Macromolecular carbon may be delivered to Mars via meteorites, or may have formed through hydrothermal geologic processes,” Uckert said.

Continuing to Explore Life on Mars

According to the researchers, determining the true origin of the carbon will ultimately require returning Martian samples to Earth, where they can be examined using far more sophisticated laboratory instruments than those carried aboard Perseverance.

“Further constraining the origin, distribution, and alteration history of the MMC observed in the Neretva Vallis mudstones requires high-resolution and high-sensitivity analyses in terrestrial laboratories, which can be facilitated by the return of the Cheyava Falls rock core, ‘Sapphire Canyon’ to Earth,” explained co-lead author Ashley Murphy, a postdoctoral research scientist at the Planetary Science Institute.

“The Perseverance Rover science payload is not designed to determine whether martian organic molecules were created by biologic or geologic processes, and our study is unable to make this distinction,” Uckert added.

The researchers say that future sample-return missions, combined with advanced laboratory analyses on Earth, may finally help resolve one of planetary science’s most enduring questions.

“The Perseverance Rover collects samples of scientifically compelling martian rocks for potential return to Earth,” Uckert concludes.“Using high-resolution terrestrial instruments to analyze these rock samples, particularly the Sapphire Canyon core collected on the Cheyava Falls rock, may provide more compelling evidence for a biologic or abiotic origin of this organic matter.”

The paper, “Spatially Distributed Complex Organic Matter Detected in an Ancient River Valley in Jezero Crater, Mars,” appeared in Science Advances on June 24, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.