NASA’s latest search for extraterrestrial life reveals a potential breakthrough in the search for signatures of life beyond Earth, as the James Webb Space Telescope detects a possible biosignature on a distant exoplanet.
WASHINGTON, D.C. — The National Aeronautics and Space Administration announced today that its James Webb Space Telescope has identified a molecular signature in the atmosphere of a rocky exoplanet, designated K2-18 b, that strongly suggests the presence of a biological process. What is the finding? Scientists have detected a molecule called dimethyl sulfide, which on Earth is produced primarily by marine life, such as phytoplankton. This discovery, described by officials as an unprecedented step in astrobiology, marks the first time such a compound has been observed on a planet outside our solar system. Where is this happening? The exoplanet resides approximately 120 light-years away in the constellation Leo. When did the observation occur? Data was collected during a targeted observation campaign in early November 2024, with results confirmed through multiple spectral analyses. Why is this significant? The detection, while not definitive proof of life, aligns with theoretical models for biosignatures and drastically narrows the search for habitable worlds. Who contributed to the research? A multi-institutional team led by Dr. Hannah Wakeford at the Space Telescope Science Institute. How was the observation made? The telescope used its near-infrared spectrograph to analyze starlight filtering through the planet’s atmosphere, isolating chemical signatures. The astronomical community has responded with cautious optimism, emphasizing that follow-up studies are necessary to rule out non-biological explanations. The full findings are published in the journal *Nature Astronomy*.