Science

New statistical method could help identify extraterrestrial life signatures

Yesterday 10:11

By: Dakir Madiha

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Scientists searching for life beyond Earth have developed a new statistical approach that could improve the detection of biological activity on planets and icy moons such as Mars, Europa, and Enceladus. Instead of focusing on identifying specific molecules linked to life, the method examines how those molecules are organized and distributed within a sample. Researchers believe this approach could help distinguish biological chemistry from non-living chemical processes, even when samples are damaged or incomplete.

The study, published in Nature Astronomy, was led by researchers from the Weizmann Institute of Science and the University of California Riverside. The team adapted statistical tools commonly used in ecology, where biodiversity is measured through two main indicators: richness, which reflects the number of species present, and evenness, which measures how uniformly those species are distributed. The researchers applied the same principles to molecular chemistry by studying the distribution patterns of amino acids and fatty acids in biological and non-biological materials.

To test the model, the scientists analyzed around 100 datasets covering a wide range of materials, including microbes, soil samples, meteorites, asteroids, fossils, and synthetic laboratory compounds. Their results showed consistent differences between biological and abiotic samples. Amino acids associated with living systems displayed higher diversity and a more balanced distribution than amino acids formed through non-living processes. Fatty acids produced without biological activity, however, showed more uniform distributions than those shaped by living organisms.

Researchers said the findings suggest that life creates not only molecules but also recognizable organizational patterns. According to the study, these statistical signatures can remain detectable long after biological material begins to degrade. Fossilized dinosaur eggshells examined during the research still preserved molecular patterns linked to ancient biological processes, despite millions of years of alteration and decay.

The team considers this persistence one of the study’s most significant findings. Scientists involved in the research said the method was capable of detecting both the distinction between biological and non-biological origins and the degree of preservation within degraded samples. This could become particularly useful for planetary missions where samples are exposed to harsh radiation, oxidation, and geological transformation over long periods.

Another advantage of the approach is that it relies on relative molecular abundance rather than precise chemical identification. Researchers said this means existing instruments aboard current and planned space missions may already be capable of collecting the necessary data without requiring major technological upgrades. Missions targeting Mars, Europa, and Saturn’s moon Enceladus could potentially apply the framework using lower-resolution analytical instruments already designed for extraterrestrial environments.

The researchers cautioned that the method does not provide direct proof of life on its own. They stressed that any future claim of extraterrestrial life would require multiple independent lines of evidence combined with geological and chemical analysis of the surrounding environment. Still, they believe statistical organization patterns could become a valuable additional tool in astrobiology, especially in missions where data remains limited and sample collection opportunities are rare.