OT: Carbon Dioxide races -> known vs unknown -> terraforming mars -> is or is not

[TerranC]

Originally posted by Loser:
Suffocation isn't the only risk. Unlike the effect carbon dioxide has on you, displaces oxygen and is more or less inert, oxygen (O2) is a caustic substance and fire hazard. If your CO2 race is not from a planet with large amounts of oxygen their equipment will need special treatment, their skin may become irritated, begin breaking down in a messy leprous goo, or simply burst into flames.

Thank God for domed colonies.

Edit: Then another question for you atmosphere experts: What would happen to an Oxygen breather in a Hydrogen-Atmosphere or a Methane-Atmosphere planet that has the same gravity as earth and atmosphere pressure as earth?

[ July 15, 2003, 14:04: Message edited by: TerranC ]

[geoschmo]

It's difficult to hypothesize since the Se4 planetary descriptions aren't very realistic to begin with. Earth isn't really an oxygen atmosphere planet, it's mostly nitrogen. To truly model alien lifeforms we need more complex planetary types. Is a Hydrogen world primarily hydrogen? Or is it mostly some inert gas and 20% hydrogen the way our atmosphere is nitrogen/oxygen? Could a biological process be even theorized that would use hydrogen or methane as it's gas for breathing? I don't really know enough about it to say.

Perhaps creatures on such a world wouldn't really breath the Hydrogen, but survive on the trace gases, or not breath at all. They wouldn't be the same as vacuum lifeforms because they would be acclimated to the pressures on their homeworld. And perhaps the Hydrogen would be neccesary becaue their bodies might react with other gases that would be toxic to their systems.

It's intersting to think about though.
I think you could pretty much make up whatever you want and it would mostly be plausible since we really don't know.

Geoschmo

[ July 15, 2003, 14:41: Message edited by: geoschmo ]

[Loser]

Originally posted by TerranC:
Then another question for you atmosphere experts: What would happen to an Oxygen breather in a Hydrogen-Atmosphere or a Methane-Atmosphere planet that has the same gravity as earth and atmosphere pressure as earth?

Methane will basically just displace the oxygen and the oxy-breather will suffocate. Dumb kids out in the country will sometimes bottle certain methane-producing substances (messy) and inhale the gases sealed in the container to get high. This is an oxy-dep high and is more easily reproduced by breathing into and form a balloon, but I guess the kids don't know that.

(Note: neither nitrous nor paint fumes are simply an oxy-dep high. These experiences are doing more than just depriving you of oxygen.)

Hydrogen, on the other hand hurts! (Personal experience.) Do not try to breathe this stuff, it is bad for you and any other oxygen breather.

Basically O2 and H2 are very reactive, while CO2 and CH4 are not so reactive. CH4 and H2 environmental suits have the additional issue that, while in an O2 environment, leaks are mixing highly combustible gases. Neither H2 nor CH4 will burn quite so hot (single bond breakages) and large masses (dome breakages) will burn relatively slowly (the Hindenburg burned so fast because of the chemicals with which the skin of the dirigible was treated), but there is great destructive potential here. Basically because the two gases are on either side of the combustive process you would see burning, but not so many outright explosions.

[ July 15, 2003, 14:59: Message edited by: Loser ]

[Erax]

Getting back to the CO2 atmosphere : it could mean any one of a number of things, but these are the more interesting possibilities :

- CO2 with some oxygen; depending on the oxygen level, CO2 'breathers' (who might actually breathe oxygen) and oxygen breathers would have few compatibility problems.
- CO2, nitrogen and other inert gases; both species would need breathers / gas tanks to survive in the other environment. The CO2 species might need an environmental suit (an insectoid species might not need a suit, if it had a resistant, airtight exoskeleton).

[Thermodyne]

CO2 breathers could be carbon cycle just like us. But evolving in a atmosphere with a high concentration of CO2 would have given them the ability to break the CO2 down into CO an O, and then use the oxygen and turn it back into CO or CO2 blowing off the excess carbon in the process. There is some evidence that long term heavy smokers do some of this on a small inefficient scale. Pulling off one of the oxygen molecules and polluting their blood with the CO, which takes a long time to blow off.

[ July 15, 2003, 16:54: Message edited by: Thermodyne ]

[kalthalior]

Interesting link: Exobiology background & theories

[Taera]

The background to my question is the fact that in my current RP my Taeran bugs are creating a close alliance with oxygen-breathers.

Thermodyne: No. Completely no. You're trying to reason with it the normal way. Not all living creatures have to use oxygen - if we cant explain it it doesnt mean it cant be.

Loser: Yep, my bugs didnt have much oxygen there, but they had some - i doubt the mere existance of the gas would cause equipment failure. Still an interesting note to remember.

Erax: Your completely right, unlike humans or mammals in general insectoids do not breathe with their skin - first of all because of the lack of such they have tough natural carpace and have multiple breathing orifices, usually along their thorax or legs.

So considering the exoskeleton is airtight and the only places that receive outside air are treated with a breather, and of course pressure and gravity are in reasonable limits, my bugs should be able to survive on an oxygen or even on a methane atmosphere right?

BTW, regarding Earth not being an Oxygen planet, technically this is true but i think it depends what the planet's flora and fauna uses, plus the atmosphere layers composition (for all i know atmosphere has plenty of H20, 03 and 02 in it) rules that the planet is, after all, an oxygen planet.