From Newsgroup: alt.astronomy
from
https://phys.org/news/2026-06-carbon-bright-angel-formation-mars.html
Organic carbon detected in Bright Angel rock formation on Mars
by Planetary Science Institute
edited by Stephanie Baum, reviewed by Robert Egan
Editors' notes
The GIST
The Perseverance rover on Mars inspects a rock dubbed Cheyava Falls with
the Scanning Habitable Environments with Raman & Luminescence for
Organics & Chemicals (SHERLOC) instrument on its robotic arm. Credit:
NASA / JPL-Caltech
In September 2025, NASA announced that its Perseverance rover had
discovered a potential biosignature, which is a substance or structure
that might have a biological origin. A new paper, published in Science Advances, unambiguously confirms the detection of organic carbon, the
building blocks of life, in the same two rocks from the Bright Angel formation, and describes in more detail exactly what we can say about
that organic matter.
Ashley Murphy, a Planetary Science Institute postdoctoral researcher,
co-led the paper with the SHERLOC instrument's Deputy Principal
Investigator, Kyle Uckert. Using the Scanning Habitable Environments
with Raman & Luminescence for Organics & Chemicals (SHERLOC) instrument
on the robotic arm of the Perseverance rover, the team performed Raman spectroscopy on multiple rocks and collected a sample from one rock
dubbed Cheyava Falls in Jezero crater's Bright Angel formation. Raman spectroscopy is a non-destructive way to detect and map minerals and
organic compounds in rocks illuminated with laser light.
The team detected the presence of macromolecular carbon (MMC), which are
large tangled networks of carbon atoms commonly found in rocks on Earth
and meteorites. MMC can arise from biotic or abiotic sources.
Billions of years ago, a river channel carried water and sediment into
Jezero crater. Fine-grained sediment settled to the bottom before
eventually hardening into the mudstone rocks the team analyzed. MMC was detected in association with these fine-grained sediments as well as
carbonate and sulfate minerals that formed later during aqueous
alteration, suggesting possible timing of organic emplacement at two or
more events across geologic history.
"While the specific formation mechanism of the MMC detected in the
Bright Angel mudstones remains unknown, this is still one of the most
exciting findings to date," Murphy said.
Organic carbon near the surface
Analysis also determined that the MMC was preserved only microns beneath
the Martian surface, which is less than the thickness of a piece of
paper. This marks the shallowest detection of MMC on Mars. It is notable
to find complex organic molecules this close to the surface in a harsh environment like Mars where sunlight and other environmental factors are
known to destroy organics.
"The Martian surface environment includes radiation and chemical
oxidants that are destructive to organics, and terrestrial laboratory simulations have shown that the survival time of organics in
Martian-like conditionsrCoespecially at or near the surfacerCodepends on factors such as the type of organic molecule and the surrounding
minerals," Murphy said. "The MMC detected in the Bright Angel mudstones
is either resistant to degradation and/or has been sufficiently shielded
by other minerals, such as clays, or iron-rich Martian soil."
Hints of wider ancient organics
Moreover, the sample was collected more than 2,000 miles away from
organic detections by NASA's Curiosity rover in Gale crater.
"It is encouraging for Martian habitability," Murphy said. "This
indicates that billions of years ago, organics may have been more than
just locally present and may have been more widely available in ancient
lakes and rivers on Mars."
Earth labs will decide
Neither Curiosity rover in Gale crater nor Perseverance rover in Jezero
crater have the large and power-consuming equipment necessary to
determine if Bright Angel contains fossilized microbial life.
Perseverance was built with the goal of detecting potential
biosignatures such as those found in the Cheyava Falls rock, making this
a "resounding win for Mars science," Murphy said. However, more powerful
tools in laboratories on Earth are needed to confirm if life or geology
is behind this discovery.
If one day the team gets their hands on samples returned from this
location on Mars, they hope to conduct mineral and organic analysis at
higher resolution and with higher sensitivity instruments to better
understand the origin of the MMC and what it can tell us about organics
on Mars.
Murphy continues to work with the SHERLOC science team to explore the
surface of Mars and use Mars analog and Raman spectroscopic studies to
improve the interpretation of rover-derived data.
Publication details
Ashley E. Murphy et al, Spatially distributed complex organic matter
detected in an ancient river valley in Jezero crater, Mars, Science
Advances (2026). DOI: 10.1126/sciadv.adx0047
Journal information: Science Advances
Key concepts
diagenesismeteoritesdiagenesismineralogy
Provided by Planetary Science Institute
Who's behind this story?
Stephanie Baum
Master's in TESOL from The New School. Passionate about language
learning and editing science news on biology and space exploration. Full profile raA
Robert Egan
Bachelor's in mathematical biology, Master's in creative writing. Well-traveled with unique perspectives on science and language. Full
profile raA
Explore further
Mars rover detects never-before-seen organic compounds in new experiment
--- Synchronet 3.22a-Linux NewsLink 1.2