Exoplanet Biosignatures · O₂ + CH₄
unseel.com · transmission spectroscopy · ~1–2 ppm feature depth
transit depth 0 ppm
O₂–CH₄ disequilibrium
phase
Host star
Atmosphere (O₂)
Methane (CH₄)
Absorption dip
Unseel.com · Exoplanet Biosignatures