Comment on "Earth-like"
jasondj@ttrpg.network 11 months agoThe mean surface temperature of Venus is only 464C.
But, with 93x the atmospheric pressure of earth, water boils at around 300C.
So…what is it that makes it difficult to thrive beyond 100C? Is it strictly the temperature, or is it the properties of water at that temperature? If it’s the latter, I wouldn’t be so surprised.
Also keep in mind that photosynthesis was a genetic accident that just happened to work really, really well, and the ability to process sunlight directly into energy was what allowed microorganisms to move away from thermal vents.
Thorry84@feddit.nl 11 months ago
It’s the temperature, a lot of chemistry doesn’t work at higher temperatures because everything is too unstable. There is simply too much energy messing things up. This is why having a surface temperature that allows for liquid water to be present is such a good indicator for life. A lot of chemistry for life as we know it works at liquid water temperatures and water does play a big part as well.
The pressure would be less of an issue, there is plenty of life on Earth that thrives at huge pressures.
I’m pretty sure life on Earth evolved at the surface (or even in the atmosphere, it is thought lightning plays a part) and only adapted to use the vents later on. I’m not sure life could get started at those volcanic vents.
AeonFelis@lemmy.world 11 months ago
I think their point was that the pressure “balances out” the temperature - so that enough of these chemistry does remain stable even though the temperature is high. For example - the water remains liquid because of the pressure, so that’s one requirement for life that gets fulfilled.