Sample analysis of Mars Instrument on NASA’s Curiosity Rover detected decane, anteca and dodecane molecules in Gale Crater samples.
This graphic shows the long chain organic molecules, decane, undercane, dodecane, and rover of curiosity from NASA. Image credit: NASA/Dan Gallagher.
“The main scientific goal of Curiosity is to quantitatively assess the possibility of Mars’ habitability in the past or present,” says Dr. Caroline Freissinet, researcher at Atmosphères ET Observation Spatiales at CNRS and Laboratoire.
“Sample analysis in the MARS (SAM) instrument suite on a rover is dedicated to this task by employing inventory of organic and inorganic compounds present on the surface of Mars as potential chemical biosignatures and investigating the nature of the conservation.”
Using SAM instruments, researchers analyzed molecules released from excavated mudstone samples called Cumberlands, collected in Yellowknife Bay, the geological layer of Gale Crater.
They were able to detect three long chain alkanes: decane (c)10htwenty two), unedecane (c11htwenty four), and dodecan (c12h26).
“These long carbon chains, which contain up to 12 consecutive carbon atoms, can exhibit similar characteristics to the fatty acids produced on Earth through biological activity,” the researchers said.
Dodecane represents the highest molecular mass organic molecule ever identified on the surface of Mars.
“Detection of long-chain alkanes shows various causes of organic matter and storage mechanisms in Cumberland samples,” the scientists said.
“Clays and sulfate minerals are expected to play an important role in this long-term storage.”
According to the author, the source of Mars’ long-chain alkanes remains uncertain.
“Laboratory experiments support sources from the saturated forms of linear chains, primary carboxylic acids, i.e. decano acids, dodecano acids, and tridecano acids, for decane, undecano and dodecano acids, respectively,” they said.
“Abiotic processes can form these acids, but are considered to be a universal product of biochemistry, on the ground and perhaps Mars.”
“The origin and distribution of these molecules therefore has great interest in searching for potential biosignatures on Mars.”
Survey results It will be displayed in Proceedings of the National Academy of Sciences.
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Caroline Freecinet et al. 2025. Long chain alkanes are preserved in the mudstones of Mars. pnas 122 (13): e2420580122; doi: 10.1073/pnas.2420580122
Source: www.sci.news