Did Mars once have life as we know it deep in its ancient past? A recent study published in Proceedings of the National Academy of Sciences might be one step closer to answering that question as an international team of almost two dozen researchers investigated findings from NASA’s Mars Curiosity rover that could help identify signs of ancient life on the Red Planet.
For the study, the researchers analyzed samples collected by Curiosity within Gale Crater on Mars, which the car-sized rover has been exploring since it landed there in August 2012, using Curiosity’s Sample Analysis at Mars (SAM) mini-lab. After careful analysis, the researchers identified fatty acid fragments decane (C10H22), undecane (C11H24), and dodecane (C12H26) at the tens of picomole (pmol) level, with one pmol equivalent to one-trillionth of a mole, and one mole equivalent to 6.02214076 x 1023 entities of a substance (i.e., atoms, molecules, etc.). Despite these very small amounts, the identification of decane, undecane, and dodecane is a crucial piece in learning if life once existed on Mars, as fatty acids are considered the building blocks of life on Earth.
Diagram depicting the organic molecules decane, undecane, and dodecane. (Credit: NASA/Dan Gallagher)
“Our study proves that, even today, by analyzing Mars samples we could detect chemical signatures of past life, if it ever existed on Mars,” said Dr. Caroline Freissinet, who is an astrochemist at the French National Centre for Scientific Research (CNRS) and lead author of the study.
As noted, Curiosity landed in Gale Crater on Mars in August 2012 and has conducted groundbreaking science with the goal of answering whether Mars once had life as we know it at some point in its ancient past. This study comes as a 2024 study published in Geology discussed that Gale Crater might have hosted liquid water for longer than previously thought, thus strengthening the argument that life could have existed on the Red Planet billions of years ago.
“There is evidence that liquid water existed in Gale Crater for millions of years and probably much longer, which means there was enough time for life-forming chemistry to happen in these crater-lake environments on Mars,” said Dr. Daniel Glavin, who is a senior scientist at NASA’s Goddard Space Flight Center and a co-author on the study.
What new discoveries about potential ancient life on Mars will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Proceedings of the National Academy of Sciences, NASA JPL, Geology
