7.06.2026

Poll of nearly 500 scientists reveals how rapid surveys can take researchers’ pulse on controversial topics

A survey showed fewer than 7% of astrobiologists believed scientists had found signs of extraterrestrial life on exoplanet K2-18b.NASA; ESA; CSA; JOSEPH OLMSTED/STSCI; NIKKU MADHUSUDHAN/IOA

Last year, when astronomers announced the atmosphere of a distant planet, K2-18b, contained promising signs of life, the claim generated media headlines calling it the “strongest evidence so far” of life beyond the Solar System. But many astronomers did not find the evidence persuasive.

Now, a paper published today in Nature Astronomy quantifies that skepticism. In a survey of 496 astrobiologists sent out eight days after the original claim, only 6.6% agreed or strongly agreed that “scientists have probably found extraterrestrial life on exoplanet K2-18b.” The authors say the study shows how quick but wide-reaching surveys could be deployed to take the pulse of a scientific community, helping inform public understanding of scientific questions.

The effort is “supervaluable and important,” says University of Cambridge psychologist Sander van der Linden, who studies disinformation. Behavioral science shows people make judgments based on their perception of scientific consensus, he says, and so the rapid polls could help protect the public from potential misinformation.

The poll is one of the first few outputs from the Centre for Scientific Community Opinion Polling and Evaluation (C-SCOPE), which has spent the past 3 years refining its methods to rapidly measure scientific consensus, says founder Peter Vickers, a philosopher of science at Durham University, where the institute is based. C-SCOPE has developed a network of representatives at 80 institutions around the world, who help design and administer the surveys.

Astrobiology has provided a useful playground for C-SCOPE to test its survey procedures. Last year, the team found that in a sample of 521 astrobiologists, 86.6% agreed or strongly agreed that “it is likely that extraterrestrial life (of at least a basic kind) exists somewhere in the Universe.” The team also sent out a similar survey about evidence for ancient extraterrestrial life on Mars, finding that, compared with the K2-18B results, more astrobiologists—15.1%—agreed the evidence was persuasive.

The results are “remarkably in line with my own personal scientific opinion after having read the papers and discussed them with colleagues,” says Sara Seager, an astrobiologist at the Massachusetts Institute of Technology. Quantifying a community’s opinion is helpful, she says, “compared to me just saying, ‘Hey, no one believes this.’”

C-SCOPE’s first proof-of-concept survey cast a broader net. In June 2023, the institute contacted more than 20,000 scientists in 12 countries, asking them to respond to a single statement: “Science has put it beyond reasonable doubt that COVID-19 is caused by a virus.” They received 6807 responses—a much higher response rate than typical for surveys—with 93.2% of respondents agreeing or strongly agreeing with the statement, the authors reported in a 2024 PLOS One paper. The figure may seem low for such an uncontroversial statement, Vickers says. But the survey sample was very broad, including chemists, physicists, and earth scientists as well as biologists and health scientists. Many scientists chose the “neutral” option, suggesting they did not feel they had the relevant expertise.

This shows how sending a survey to too many kinds of scientists could undermine its results, says John Cook, a psychology researcher at the University of Melbourne. Consensus in climate science, for instance, is higher when focusing on climate scientists specifically rather than all earth scientists. Still, Vickers thinks it’s generally worth surveying widely, casting a net across disciplines or broadly within a discipline. Narrowing the pool of experts risks biasing the sample, which could undermine trust in the results, he says. It also risks missing minority opinions that may eventually become mainstream.

Rapid polling is a “great idea,” Cook says, but slower, more laborious methods to ascertain consensus are still beneficial. For example, Delphi processes, which generate multiple rounds of feedback on a set of statements to gather and refine expert opinion, have the benefit of actually bringing people to a point of agreement, says Temple University philosopher of science Miriam Solomon. “When you put people together and make them talk to each other, they change their views sometimes.”

At some point, C-SCOPE will branch out into more politically contentious topics, including climate change, Vickers says. The group may, for example, track changes over time in scientists’ beliefs about the likely level of global warming by 2100. He also sees potential in rapidly polling scientists on topics in the headlines—such as the claim that Tylenol taken during pregnancy causes autism—possibly generating results in as little as 2 days. But his team would have to take great care over the question they ask, he says, to preserve their neutrality and trust in the results. “We want to remain squeaky clean.”

Quelle: AAAS