Meteorite from Mars: There was no biological process

Antarctica, 1980s: A fragment of a meteorite was collected from Mars during a research expedition, and news of the discovery ends up on the front pages of all newspapers. Inside the meteorite – classified as ALH84001 – are actually organic materials, i.e. compounds of the elements that form the basis of life (such as carbon, hydrogen, oxygen, nitrogen, sulfur), microscopic deposits that appear to have been produced only by living things and even what appeared to be fossils Microscopic extraterrestrial organisms. Evidence for the existence of “Martians”? For some, yes, but then the debate among scholars ended in nothing.

Today, a research group from the Carnegie Institution for Science in Washington returned that sample and asked NASA to be able to analyze a very thin portion of it using modern techniques, including nanoimaging, isotope analysis in rocks and spectroscopy. (which uses light to study the chemical composition of matter).

Back in time. Explains Andrew Steele, one of those who studied the sample and conducted the study published in the journal Science.

The results will leave no shadow of doubt: the properties within ALH84001 can be obtained from non-biological processes that even on Earth give life to molecules that are also made of carbon. Steele explains: “What we observed can be interpreted as organic matter produced in a brine containing carbon dioxide passing through igneous rocks. It could be the bedrock, the substrate from which life could evolve.”

How did all this happen? Through the processes already known as serpentineIt is a phenomenon that occurs when certain igneous rocks (formed by solidification of lava or magma) rich in iron and magnesium come into contact with circulating water. or like carbonation, where the rocks react with slightly acidic water in which carbon dioxide is dissolved, resulting in the formation of carbonaceous substances. What remains questionable is whether the two processes occurred consecutively or at the same time, even if the water had not circulated for a long time.

Arcs: Among the chemical elements produced during the serpent process is methane, which has been frequently discovered within Gale Crater since then. Curiosity Rover (Not to be confused with determination, which has been exploring Jezero crater since spring 2021). This could mean that such processes are still going on, assuming that there is still water circulating under the surface of Mars.