Possible Biosignatures Found on Exoplanet K2-18b

Astronomers using the James Webb Space Telescope have detected strong evidence of dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) in the atmosphere of exoplanet K2-18b, about 120–124 light-years from Earth. On Earth, these gases are produced almost exclusively by living organisms, especially marine phytoplankton, making them potential biosignatures. K2-18b, classified as a Hycean world, has also shown signs of water vapor, methane, and carbon dioxide, indicating possible conditions for life. While the detection of DMS and DMDS is considered the strongest sign yet of possible extraterrestrial life, scientists caution that non-biological processes might also account for these gases and the current evidence is at a three sigma confidence level, which is not scientific proof. The findings have intensified both optimism and debate within the scientific community and fit into humanity's long-standing search for life beyond Earth. Further observations and analysis are expected over the coming years to clarify these results.