Atmospheres

[Slick]

Originally posted by Imperator Fyron:
[QB]Chlorine makes 0 sense for a life-supporting atmosphere. It is too reactive of an element and tends to destroy any molecules it comes in contact with. Complex, sentient lifeforms evolving on a chlorine atmosphere world would be too unbelievable.
QB]

Oxygen is much more reactive than chlorine. Therefore by your reasoning it makes 0 sense for it to be a life-supporting atmosphere.

[Krsqk]

Umm, Fyron, you're assuming we can only have atoms with integral numbers of protons. What about element number 48.75? Hmmm?

[Slick]

Originally posted by Krsqk:
Umm, Fyron, you're assuming we can only have atoms with integral numbers of protons. What about element number 48.75? Hmmm?

Although I would never assert that the absence of evidence is evidence of absence... I would point out that nothing like this has ever been observed. Additionally, under our current understanding of physics, protons are made up of smaller parts called quarks. Our current understanding, which is supported by experiment, says that these quarks are only stable in certain configurations. Thus, our current model of physics, which is strongly supported by experiment, does not allow for fractional numbers of protons.

However SE4 is a game where anything is possible.

Slick.

[Baron Munchausen]

Of course, this whole debate about the 'suitability' of one atmosphere or another for life is presuming that there are distinct 'types' of atmospheres. This is even more UNrealistic than trying to claim that life could exist in a predominantly chlorine atmosphere. I hope that SE V will have much subtler gradations of 'suitability' to account for the highly variable composition of various elements that would exist in real atmospheres. Balancing atmospheric gases could be a field of terraforming all to itself. (As opposed to the very crude 'conVersion' currently offered.)

Then with temperature, gravity, and radiation levels we could finally have some believably realistic environmental management on our worlds.

[Desdinova]

sounds like you are talking about stars' planetary characteristics. just a sliding bar to determine where your races habitable/tolerable ranges are. no specific atmosphere, gravity or radiation selected.

[Erax]

Fyron, once again we have the opportunity to disagree.

Life is sustained by a series of chemical reactions which take place in a solvent, which for all known life is water.

I agree that chlorine is incompatible with water-based lifeforms, so a chlorine-breathing creature would need to use another solvent, for example trichloroethylene.

AFAIK, chlorine-breathing lifeforms are not impossible, and in fact are more plausible than CO2 or argon breathers.

There are a few SF books that feature chlorine breathers (James White's Sector General series, for example) which is why I think they included the chlorine atmosphere in SE3.

[Suicide Junkie]

Wouldn't CO2 breathers be very similar to our plants?