Post AtAbA9eYFQ7eE6px6O by brianvastag@sciencemastodon.com
 (DIR) More posts by brianvastag@sciencemastodon.com
 (DIR) Post #AtAbA8OCwhSGJ8BNzM by brianvastag@sciencemastodon.com
       2025-04-17T03:46:35Z
       
       0 likes, 1 repeats
       
       I remember having conversations with Joel Achenbach (who wrote this piece) about how the first biosignature detections from exoplanets will be ambiguous & that the whole field of exobiology is fraught with this issue...it's going to be very difficult to declare *anything* other than, I dunno, a video call? - as proof of life. Still, it's an exciting discovery - a molecule that on Earth is only made by life has been detected (probably) on a distant planet. https://www.washingtonpost.com/science/2025/04/16/alien-life-exoplanet-webb-telescope/#science
       
 (DIR) Post #AtAbA9eYFQ7eE6px6O by brianvastag@sciencemastodon.com
       2025-04-17T03:48:02Z
       
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       Even if we detect abundant molecular oxygen (O2) in an exoplanet atmosphere, there is some non-zero possibility some geologic or non-biological process made it. Here, it's a sign of life. Elsewhere...it's *probably* a sign of life too. But it's not a certainty.