(ORDO NEWS) — Organic molecules found in a meteorite that came to Earth from Mars were synthesized from interactions between water and rocks that took place on the Red Planet about 4 billion years ago, according to a new analysis by a team led by Andrew Steele. ) from the Carnegie Institution, USA.
This meteorite, known as ALH 84001, was discovered in Antarctica in 1984 and is considered one of the oldest known bodies from the surface of Mars to have ever reached Earth.
For many years, scientists have debated the origin of the organic carbon found in the ALH 84001 meteorite, discussing the possibility of various abiotic processes associated with volcanic activity, collisions of celestial bodies with the Martian surface or hydrological factors, and up to the potential remains of ancient life forms on Red planet or contamination of meteorite matter by terrestrial life forms.
In the new work, Steele’s team used a range of state-of-the-art sample preparation and analysis techniques—including nanoimaging, isotope analysis, and spectroscopy—to elucidate the origin of organic molecules in ALH 84001 meteorite samples.
The authors found signs pointing to interactions between water and rocks, similar to two important geochemical processes occurring on Earth. One of these processes, called serpentinization, occurs when iron- or magnesium-rich igneous rocks chemically interact with circulating water, changing their mineralogical composition and releasing hydrogen.
Another process, known as carbonization, involves interactions between rocks and slightly acidic water containing dissolved carbon dioxide and results in the formation of carbonate class minerals.
It remains unclear whether these processes in the aquatic environment around the minerals proceeded jointly or sequentially, however, the facts indicate that the interactions between water and rocks could not proceed for too long. It is obvious, however, that the organic carbon in the composition of the meteorite substance was formed as a result of the reduction of carbon dioxide, the authors summed up.
Contact us: [email protected]