Astronomy
Occurrence Rate of Biosignature Gases in Theoretical Exoplanet Atmospheres
Quick fact
Theoretical models suggest that only a small fraction of rocky exoplanets in the habitable zone might have atmospheres containing detectable biosignature gases, with oxygen and methane being among the most promising but also prone to false positives.
Why this is interesting
If a distant planet had life, what gases would we expect to find in its atmosphere? And how likely would we be to spot them?