26.05.2026

Astronomers admit in a new study that they may be missing signs of extraterrestrial life on other planets.

The research published in Nature Astronomy suggests that there may be many “false-negative” determinations of whether alien life is present on a planet or moon being studied and that space exploration missions and projects might have to be redesigned.

“We should be aware of these false-negative results,” says lead author Inge Loes ten Kate, professor in astrobiology at Utrecht University and the University of Amsterdam in the Netherlands.

“It means there are shortcomings in recognising the existence of life. These shortcomings are not yet high on the research agenda.”

The search for extraterrestrial life includes space missions to planets and moons in our solar system including robots on Mars looking for signs of ancient life.

It also includes the search for chemical signatures in the atmospheres of planets orbiting distant stars which may be the result of alien metabolisms, ecosystems or even industry.

Astrobiologists know about false-positives in the search for alien life.

These are results – like human-made interference, oxygen created by non-organic chemical processes and even structures which appear to be non-natural – which may appear to the vibrant imagination like signs of extraterrestrials but can be explained by other means.

It’s trickier to ascribe false-negatives.

They could arise because the traces of alien life may be so miniscule that they can be missed or they have not been preserved in a detectable way at all. Our detection methods could be limited in themselves.

“A simplified example: if there is life under a rock, and you only look at that rock from above, that life will go unnoticed,” ten Kate says.

“So, investigate thoroughly whether the conditions for the existence of life forms are present in the environment and whether you can recognise patterns on the surface of a celestial body.”

Ten Kate says this could be a life-or-death question for potential extraterrestrial organisms.

“There is a danger that policymakers will approve the premature exploitation of raw materials on planets with the risk of irreversibly destroying unnoticed life.”

“We therefore advocate for the development of a targeted research strategy that systematically addresses these risks, in which we must combine laboratory experiments with modelling research and fieldwork. Space missions and instruments are designed to detect potential signs of life, but the risk of overlooking something is not taken into account,” ten Kate says.

“The search for signs of life should go hand in hand with better-defined questions and testable hypotheses to justify specific measurement or observation targets.”

Ten Kate and colleagues suggest that artificial intelligence could be a powerful tool for the kinds of pattern recognition needed to overcome these shortcomings.

“You might well uncover things that we would never be able to see on our own,” ten Kate explains. “And with new observations, you can then work out how and where they fit into such a pattern.”

Indeed, alien life is inherently alien meaning we may not even be able to narrow down what to look for.

“That question goes to the heart of our problem, because we tend to look for things we already know,” ten Kate says. “We therefore need to understand very clearly what kind of life is possible in a particular place, what the conditions for that life are, and how we can recognise the traces of that life. And even then, we might overlook things.”

Quelle: CONNECTSCI