How is it that methane is such an indicator for life? Correct me if I'm wrong, but hasn't science established significant amounts of methane in the upper atmospheres of both Uranus and Neptune? I don't think anyone is expecting to find life on either of those two worlds.
Methane is generated by biological activity (e.g., decomposition) and can indeed indicate biological activity. I can’t find it here, but at home (somewhere) I’ve got a paper or two from the late Thomas Gold discussing methane and other hydrocarbons on other celestial bodies.
Plenty of methane around Demorat’s Uranus butt signs
of life are fading fast........