Starship Asterisk*

Whether methane is a biomarker depends on what sort of environment you find it in. Are conditions such that any methane tends to break down, or get transformed into something else? If that's the case, yet methane is still present, then it must be replenished from somewhere. Living organisms and volc...

Not sure about the 'lots of light' angle. Even ignoring the inverse square law for the amount of light, the atmosphere is very thick, plus most of the higher-energy radiation, useful to get reactions going, would probably be absorbed or weakened by the atmosphere (any titanoids reading this, please...

...These life forms on Titan would need to "eat" nutrients and to get rid of waste products. Would this amount of biomass change the composition of Titan, for example of the atmosphere of Titan, in a way that would be in any way measurable? Could we say that there is probably life on Tita...

Our oceans support life because of Dissolved Oxygen in the water. For the first one or two billion years of life on Earth, the oceans supported life without any appreciable amount of oxygen dissolved in them. The life forms of that era thrived perfectly well without free oxygen, which in fact was t...

Our oceans support life because of Dissolved Oxygen in the water. When fish respirate, they aren't stripping the O from the H2O, they are removing dissolved oxygen from the water through their gills. The Eatrh Water Cycle acts to replinish the dissolved oxygen, from our atmosphere, so that the sea ...

Planets and moons are surprising. Yes! That is why I'd suggest that it is important not to jump to conclusions, about what sort of things or processes may or may not be present on unexplored worlds. When I was a kid in the sixties, my parents had a coffee table Reader's Digest style book about the ...