Atmosphere types

[JurijD]

Originally posted by Imperator Fyron:
Argon was in SE3. So was Chlorine... that would be a nasty atmosphere to evolve in...

Actually looking at this from a biochemical perspective any atmospehere that includes a strong oxidizing agent is a good atmosphere.... why?

well because the point of an atmosphere is that is provides a place where living organisms can deposit the electrons they get from eating reduced compounds... and this flow of electrons from reduced foods to oxidizing atmospehre drives all living beings.

Therefore as we have an Oxygen atmosphere we're pretty well built as Oxygen is a very powerful oxidant (compared to Chlorine for example).

So of the Atmosphere types in SE IV these would be valid in reality:

Oxygen: YES, very good atmosphere, prolly the best one u can have as the energy per mass density in reactions with oxygen is the 2nd highest one. Only if an atmosphere had Fluorine one could have a higher energy/mass ratio in chemical reactions... But fluorine is not an option because although its thermodinamically favourable to oxygen, its kinetically so unstable that is would react with every other reducing componund on the planet and such an atmosphere would destroy itself in a few months probably.
None: ? maybe, but these beings wouldn't be very evolved because they would have to carry 2 types of food with them: an oxidant and a reducent... and that would icrease your weight/energy ratio by a factor of 2.
Methane: On this world beings would have to EAT an Oxidant if they wanted to breathe Methane, because Methane is a reducing agent. And since any good (easily available) oxidant is mostly in a gas form, these beings would also be very primitive because they wouln't be able to store their food source very good (u cannot build up a big supply of 2 gasses in your body, especially not 2 inert gases such as Methane and Oxygen)
Hydrogen Same as with methane, altough I cannot imagine a planet with a mixture of hydrogen and an oxydizing agent in it... for obvious reasons. The thing would again be very kinetically unstable
Carbon dioxide With this gas u cannot drive any meaningful chemical reactions that produce energy and therefore it would be totaly useless as a breathing gas. Beings here would be something similar as with None (in terms of energy production)

So Chlorine (as its also a good oxidant) wouln't be such a "nasty" atmosphere for beings to evolve in.

[Baron Munchausen]

More importantly, it provides one more option in the game. Chlorine is chemically active so you can imagine at least a plausible form of life that uses chlorine reactions. It would be nice to have chlorine planets again for SE5. In fact, I hope he makes it possible to define your own atmosphere types for SE5!


Hey, it's post #3333!

[Fyron]

Well, it is safe to assume that nearly any atmosphere has more than just a single gas in it. CO2 can very likely have enough free oxygen floating around to be used, for example.