From mudstones on Mars to strange gases in exoplanet atmospheres, tentative evidence for extraterrestrial life is starting to ...

Phosphine gas detected on Venus suggests the presence of oxygen-free microbial life, though findings are still unconfirmed. Such life would be invisible to the naked eye and fundamentally different ...

The finding suggests phosphine—a potential biosignature—shouldn’t be viewed as evidence of alien life until natural, non-biological sources are ruled out. Reading time 5 minutes For scientists, the ...