Habitability and biosignature claims on exoplanets
Life on a distant planet might reveal itself through gases in its atmosphere that are hard to make without biology, such as oxygen together with methane. Every claimed detection so far is disputed, and whether planets around small red stars can even keep atmospheres is unknown.
Why it matters
It is the observational route to finding life beyond Earth.
Review
E. W. Schwieterman et al., Exoplanet Biosignatures: A Review of Remotely Detectable Signs of Life, Astrobiology, 2018. https://doi.org/10.1089/ast.2017.1729 reference checked
Timestamp record
- Signed record
- 59b283291ab5…
- Public log
- Entry 29, in checkpoint 2,123
- In the log by
- Block 969,698, 2026-10-03
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