NASA finds possible signs of ancient life on Mars

A rock imaged by the US Aeronautics and Space Agency's (NASA) Perseverance rover on Mars showed signs of ancient life.


According to NASA, scientists working on the findings of the Perseverance rover have identified a rock with signs that it may have hosted microbial life billions of years ago.

The arrowhead-shaped rock, named “Cheyava Falls” by scientists after a waterfall in the Grand Canyon, contains interesting features that could be clues to whether Mars was home to microscopic life in the past.

Analysis by instruments on the Perseverance rover showed that the 1-meter-tall, 60-centimeter-wide rock bears traces that fit the definition of ancient life.

MAY BE SIGNS OF WATER AND LIFE BILLIONS OF YEARS AGO

The rock was found to show water flowing billions of years ago in the area discovered by the rover and exhibits chemical traces and structures likely created by life forms.

The “Cheyava Waterfall”, the 22nd rock sample Perseverance examined, was found on July 21 while exploring the northern edge of the Neretva Vallis, a 400-meter-wide ancient river valley carved by water flowing into the Jezero Crater long ago.

Several scans of Cheyava Falls by the rover's “Scanning Habitats for Organics and Chemicals with Raman and Luminescence (SHERLOC)” instrument showed that it contains organic compounds.

It was noted that these carbon-based molecules are considered to be the building blocks of life, but they can also be formed by non-biological processes.

'CHEYAVA WATERFALL'

“Cheyava Falls is the most amazing, complex and potentially the most important rock ever studied by Perseverance,” said Ken Farley of the Perseverance project team at the California Institute of Technology in Pasadena. “We've made the first convincing identification of organic matter, distinct colored spots indicating chemical reactions that microbial life could use as a source of energy, and the first convincing evidence that the water necessary for life has passed over the rock. However, we have not been able to discover exactly how the rock was formed and to what extent nearby rocks heated 'Cheyava Falls' and contributed to these features.”

“Cheyava Falls has large white veins of calcium sulfate running through the rock, with bands of material between them suggesting the presence of hematite, one of the minerals that gives it the rusty reddish color typical of Mars.

A closer look at these red areas also revealed numerous irregularly shaped, millimeter-sized off-white spots surrounded by black material resembling a leopard pattern.

Perseverance's “Planetary Instrument for X-ray Lithochemistry (PIXL)” instrument determined that these black halos contain both iron and phosphate.

David Flannery, an astrobiologist at the University of Queensland in Australia and a member of the Perseverance team, said: “These spots are a big surprise. On Earth, such features in rocks are usually associated with the fossilized remains of microbes living underground.”

LEOPARD PATTERNS MAY ALSO HAVE BEEN FORMED BY MAGMA

On the other hand, it is also possible that the millimeter-sized olivine crystals and sulfate detected in the rock could have been formed by the crystallization of magma on the planet and adhered to the rock at uninhabitable temperatures, forming leopard patterns through non-biological processes.

Scientists are also evaluating other views on the observed tracks and state that further research is needed for a definitive finding of ancient life.