Scientists find hint of alien life on distant world
NASA's James Webb Space Telescope has detected a possible signature of life on planet K2-18b


What happened
Astrophysicists reported Wednesday they had found significant evidence that life may exist on a planet called K2-18b, some 124 light years away. The report, published in The Astrophysical Journal Letters, said NASA's James Webb Space Telescope had detected large amounts of dimethyl sulfide and/or dimethyl disulfide — gasses that on Earth are only created by living organisms — in the exoplanet's atmosphere.
Who said what
Study leader Nikku Madhusudhan, from Cambridge University's Institute of Astronomy, said the new findings point to K2-18b, discovered in 2015, being a "hycean world" covered by a deep ocean "teeming with life." The team didn't prove the existence of alien life, but "this is a revolutionary moment," he said at a news conference. "It's the first time humanity has seen potential biosignatures on a habitable planet."
Other scientists urged caution. A "molecule glimpsed in the air of a planet 729 trillion miles away is a thin reed upon which to rest what would be the historic discovery of alien life," The Washington Post said.
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What next?
The "rich data from K2-18b make it a tantalizing world," and "I look forward to seeing additional, independent work on the data analysis starting as soon as next week," said planetary scientist Christopher Glein of the Southwest Research Institute in Texas, per The New York Times. But "unless we see E.T. waving at us, it's not going to be a smoking gun."
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Peter has worked as a news and culture writer and editor at The Week since the site's launch in 2008. He covers politics, world affairs, religion and cultural currents. His journalism career began as a copy editor at a financial newswire and has included editorial positions at The New York Times Magazine, Facts on File, and Oregon State University.
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