Tuesday, May 12, 2026

SPACE/COSMOS

New method sharpens the search for alien biology



Life leaves a pattern, not just a trace




University of California - Riverside

Solar system 

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The search for life beyond Earth has a new approach that relies more heavily on statistical patterns of molecules than on any one molecule's presence. 

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Credit: NASA




For decades, the search for life beyond Earth has revolved around a key question: What molecules should scientists be looking for on other planets or moons?

A new study, published in Nature Astronomy, suggests the more revealing clue may not be the molecules themselves, but the hidden order connecting them.

“We’re showing that life does not only produce molecules,” said Fabian Klenner, UC Riverside assistant professor of planetary sciences and co-author of the study. “Life also produces an organizational principle that we can see by applying statistics.”

The researchers found that amino acids are consistently more diverse and more evenly distributed in a material sample created by a living thing than those found in abiotic or nonliving things. In contrast, the pattern reverses for fatty acids: abiotically produced fatty acids are distributed more evenly than those produced by biological processes.

This study is the first to demonstrate that this fundamental principle of life can be detected using a statistical approach that does not rely on any one special instrument. Instead, it may be possible to find this pattern in data collected by instruments already aboard current and planned space missions.

The work arrives as planetary exploration enters a new phase in which longstanding questions about the origin of life and its prevalence in the universe may finally become testable with real observational data. Missions to Mars, Europa, Enceladus, and other worlds are returning increasingly sophisticated measurements of organic chemistry. Yet interpreting those measurements remains difficult.

Many compounds central to terrestrial biology, including amino acids and fatty acids, can also form through nonbiological processes. They have been detected in meteorites and synthesized in laboratory experiments designed to mimic conditions in space. Finding such molecules alone is not enough to claim evidence of life.

“Astrobiology is fundamentally a forensic science,” said Gideon Yoffe, postdoctoral researcher at the Weizmann Institute of Science in Israel and first author of the study. “We’re trying to infer processes from incomplete clues, often with very limited data collected by missions that are extraordinarily expensive and infrequent.”

The researchers approached the problem with a statistical framework borrowed from ecology, where scientists quantify biodiversity by measuring two properties: richness, or how many species are present, and evenness, or how uniformly they are distributed. Yoffe first encountered the approach while completing doctoral work in statistics and data science, where diversity metrics were used to uncover patterns in complex datasets, including studies of ancient human cultures.

The team applied the same logic to extraterrestrial chemistry.

Using approximately 100 existing datasets, the researchers analyzed amino acids and fatty acids from microbes, soils, fossils, meteorites, asteroids, and synthetic laboratory samples. Biological samples repeatedly exhibited distinct organizational patterns that separated them from nonliving chemistry.

What surprised the researchers most was the method’s strength despite its simplicity.

Looking at the samples in this way, the researchers were consistently able to separate biological and abiotic samples with striking reliability. In addition, they were also able to see that biologically derived materials formed a continuum from well-preserved to degraded states.

“That was genuinely surprising,” Klenner said. “The method captured not only the distinction between life and nonlife, but also degrees of preservation and alteration.”

Even heavily degraded biological samples retained traces of that organization. Fossilized dinosaur eggshells analyzed in the study, for example, still carried detectable statistical signatures shaped by ancient life.

The researchers emphasize that no single method is likely to prove the existence of extraterrestrial life on its own.

“Any future claim of having found life would require multiple independent lines of evidence, interpreted within the geological and chemical context of a planetary environment,” Klenner said.

Still, the team believes their framework could become an important new tool for future missions.

“Our approach is one more way to assess whether life may have been there,” Klenner said. “And if different techniques all point in the same direction, then that becomes very powerful.”

 

When the clouds clear – the emergence of young star clusters




Stockholm University
Alex Pedrini 

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Alex Pedrini, first author and PhD Student at the Department of Astronomy, Stockholm University & Oskar Klein Centre.

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Credit: Giacomo Bortolini




The Hubble and James Webb Space Telescopes have revealed thousands of young star clusters emerging from their birth clouds. The observations, published in Nature Astronomy, show that more massive clusters clear away their natal gas faster than lower-mass clusters. The result has important implications for our understanding of star formation and how the young stars affect their surroundings.

“I was excited to see that the emerging timescale of a star cluster is related to its mass in stars. This has implications on a range of research fields, from planet formation to galaxy evolution”, says Alex Pedrini, PhD student at the Department of Astronomy at Stockholm University and first and corresponding author of the study.

Alex Pedrini is part of the Galaxy group and the FEAST* team at the Department of Astronomy and Oskar Klein Centre (OKC) at Stockholm University, where he studies how stars are born and how they influence their host galaxies. Most stars form in clusters hidden inside dusty gas clouds, where massive young stars release energy that blow away this material and slow down further star formation. 

Estimating the timescale for emergence 

The research team used the James Webb and Hubble Space Telescopes to measure the emission at ultraviolet to infrared wavelengths of thousands of young star clusters in four nearby galaxies: M51, M83, NGC 628 and NGC 4449, which are all in the Local Volume, that is within 30 million light years of our Galaxy, the Milky Way.

Different wavelenghts of light reveal different stages in the process as young star clusters emerge from their dusty birth clouds. Infrared light allows us to see through warm dust and detect the newborn clusters during the emergence process, while visible light reveals the stars after the gas has been dispersed. 

“By comparing how many clusters we see in each stage, we can estimate how long it takes for young star clusters to emerge and how this depends on their mass in stars,” says Alex Pedrini. 

The authors detected around nine thousands young star clusters in all the four galaxies, finding that more massive clusters emerge, on average, quicker than lower mass clusters.

Understanding of early stages

The findings suggest that massive star clusters may form in very dense regions where gas is more efficient at forming new stars than in environments where low-mass clusters form. Together with results from simulations, this work provides a more complete understanding of the early stages of star cluster emergence.

“Because massive star clusters disperse their birth gas more quickly, more of their energetic and ionizing radiation can escape into the galaxy, making them important sources of ionizing radiation in galaxies”, says Alex Pedrini. 

Synergy between observations

“This study is a team effort enabled by the unique synergy between HST and JWST observations. Understanding how star clusters form and affect their environment is one of the main goals of the FEAST team”, says Angela Adamo”, associate professor at the Department of Astronomy and leader of FEAST, addressing fundamental questions related to star formation and stellar feedback across a wide range of galactic environments.

Opens for more knowledge

Understanding the emergence process in detail can help in figuring out how galaxies re-ionized the early universe, even though the galaxies in this study are in our local universe. The results also have implications for planet formation: in regions dominated by massive clusters, faster gas dispersal may reduce the time available for planets to form. 

“With upcoming JWST observations, we will be able to study a wider variety of galaxies and more extreme cosmic environments, helping us uncover how young star clusters emerge and how stars and planets begin their lives across the Universe”, says Alex Pedrini.

FACTS
*FEAST (Feedback in Emerging Extragalactic Star ClusTers) is a James Webb Space Telescope Cycle 1 international program led by Angela Adamo and involving several researchers from Stockholm University: Alex Pedrini, Arjan Bik, Giacomo Bortolini, Helena Faustino Vieira, Jens Melinder, and Göran Östlin. Together with a team of about 30 astronomers from around the world, the collaboration aims to address fundamental questions related to star formation and stellar feedback across a wide range of galactic environments.
Read more

Find more information and images in a press release from ESA

Angela Adamo 

Angela Adamo, Associate professor at the Department of Astronomy and leader of FEAST.

Credit

Arjan Bik

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