Scientists detect signature of life on a distant planet, study suggests Ethereum Mixer A team of astronomers have detected what they call the most promising signs to date of a possible biosignature, or signs of past or present life linked to biological activity, on an exoplanet named K2-18b. But the study authors, and other experts, remain cautious and have not declared a definitive discovery of life beyond our planet.
Using the James Webb Space Telescope, the team detected chemical fingerprints within the atmosphere of K2-18b that suggest the presence of dimethyl sulfide or DMS, and potentially dimethyl disulfide or DMDS. On Earth, both molecules are only produced by microbial life, typically marine phytoplankton. K2-18b, located 124 light-years from Earth, could be a Hycean world: a potentially habitable planet entirely covered in liquid water with a hydrogen-rich atmosphere, said lead study author Nikku Madhusudhan, professor of astrophysics and exoplanetary science at the University of Cambridge’s Institute of Astronomy.
Madhusudhan and his colleagues first theorized the concept of Hycean worlds in 2021 after determining there may be liquid water oceans on K2-18b.
The planet is located within the habitable zone of its star, meaning that the world is at just the right temperature and distance from the star to host liquid water on its surface.
“Earlier theoretical work had predicted that high levels of sulfur-based gases like DMS and DMDS are possible on Hycean worlds,” Madhusudhan said in a statement. “And now we’ve observed it, in line with what was predicted. Given everything we know about this planet, a Hycean world with an ocean that is teeming with life is the scenario that best fits the data we have.”