March 29, 2023

A simple reason can explain the absence of life on Mars

Researchers in Chile discovered some mysterious signs when they tested the mineralogy at Pedra Vermelha, an ancient river mouth in Chile’s Atacama Desert that contains sand and rock rich in hematite and mudstone. This region is often used as a model for the Red Planet, due to its geological similarity to parts of it Mars.

Experts argue that improving our ability to identify long-dead “microbial dark matter” requires improving current technology. This is because without it, life on Mars would remain a mystery, especially if the life we’re looking for existed billions of years ago, when the planet was much hotter and wetter than it is today.

Researchers from the Autonomous University of Chile found that 40% of genetic sequences could not be assigned to any specific taxon (a unit of classification associated with the scientific classification of organisms), while nearly 9% were classified as “unclassified”. This lack of classification is referred to by researchers as the “dark microbiome.” Pedra Vermelha, in the Atacama Desert, may contain new and unknown microbial species not found anywhere else.

Researchers in Chile analyzed samples of red rocks with test instruments designed for use on Mars or intended for Mars, and the results show that detecting microorganisms is more challenging, with limited or no detection in most cases.

Although the Perseverance rover found “strong signs” of organic matter on Mars last year, these molecules are not necessarily indicative of life. Chilean researchers say that it is difficult, if not impossible, to detect low levels of organic compounds in Martian rocks, depending on the instrument and technology used. These findings reveal how difficult it is to identify life on Mars, even if it does exist.

Published in Nature Communications, a recent study stresses the importance of collecting samples from Mars and returning them to Earth in order to determine conclusively whether or not life exists on the Red Planet. NASA has been planning this cluster for years, but the challenge is enormous because it has to send a mission to the distant planet. The date for such an undertaking has been set for the years 2030 or 2040, however, it is expected that, by then, technology will have advanced enough to examine the samples collected more thoroughly.