Atmospheres that don't mix

[kilmore]

Here's a question for the chemists. Let's say planet A has an atmosphere, thick in some element in the atmosphere, but not to the extent that visitors can't handle a week or two and natives can get either acclimatized or modified to handle it.

Planet B has the same situation, only with a different chemical. Traveller from planet A gets a lungload from planet B and "Gah! Erk!" *die*

First question, can this happen after spending a week in jumpspace in Imperial Standard Atmosphere (whatever that is)? And what chemicals work for this? I'm thinking sulfur for A and iodine for B. Big heartburn there, but I'm not sure the chemistry works.

 

[Enoki]

Arsenic would be a good one. It is poisonous to human life normally but there are some bateria on Earth that metabolize it and use it in their life processes. Arsenic can be found mainly in soil or water but it is possible to have compounds that are airborne of it. So, you could have a world where the water and atmosphere have arsenic compounds present that are needed for the local life to survive. Removed, they eventually would suffer dire consequences. The rate of occurance would depend, of course, on how necessary and in what quantity they needed arsenic in their enviroment. On the flip side persons visiting this planet would require all their air and water filtered to remove what would be a nasty poison that in high amounts would quickly produce symptoms like vomiting and nausia.

 

[BytePro]

You are looking for something airborne that would stay in the human lungs or blood (most likely) for an extended period and then interact, fatally, in another environment?

The most believable would be a pathogen - virus or bacteria, though a chemical compound, especially acting as a catalyst might work well and be even less likely to trigger a pre-mature immune response. Though the later would be less likely to naturally occur.

As to just gases and known ones... there are plenty of gases (common even), that mixed in the lungs that can potentially be deadly, but not aware of any that would last any amount of time between mixing. The most plausible (and easiest) is for you to make something up ala the above - avoid real world gases as that is more unrealistic. If it exists in the RW it is undoubtedly subject to conditions like pressures, etc. that make it rare and easily impossible given any specific situation and level of detail provided in a game.

Even without any special knowledge, consider - the nature of gases mean any gas in lungs or blood (outgassing) will be trivially detectable as part of the life support system. Anything we know of today would be accounted for. So this is extremely unrealistic and hokey to any player who would have this much basic knowledge.

Hence, use Science Fiction.

[Of course, I hope you're not planning to permanently off PCs in such a fashion, unless it is the endgame (which would sound lame, anyway - best to blow everyone up!)]

 

[kilmore]

Not trying to hurt anyone, just another hassle for the players, having the customs official say, "You can't come here if you just got offa Planet A. They're nice folks and all, but unless you want to do a circus firebreather act and never breathe with your own lungs again I wouldn't recommend it."

 

[Enoki]

You could just change the mix on more common gasses with odd results.

More helium and everyone sounds like a chipmunk....

Too much oxygen you get too much of a rush...

Nitrogen narcosis (like divers might get) from high planetary atmospheric pressure and lots of nitrogen.

The presence of small amounts of nitrogen or hydrogen cyanide from combustion processes on the planet. These in even small amounts will give someone a terrible non-stop migrane for as much as a week or more after exposure (the gaseous form is far less dangerous than the liquid variety).

A swampy world with hydrogen sulfides (rotten egg odor) or mercaptains (nuclear strength body odor) in the atmosphere from natural processes. These could be enough to cause involuntary retching or vomiting to the uninitiated.

 

[BytePro]

Not trying to hurt anyone, just another hassle for the players, ...

He he... Ah, well, a handle sounding a lot like 'kill more' just had me wonder'n

Just to play devil's advocate (i.e. a Player) - couldn't they just wear vacc suits then?

An airborne pathogen would, at least, require complete decon and probably quarantine... very interesting if both planets have pathogens that in isolation are harmless, but together are lethal.

Even more so if its really not true (maybe historically it was, or it was just mistakenly taken as fact, or was an intentionally fabricated lie...).

 

[fusor]

More helium and everyone sounds like a chipmunk....

Too much oxygen you get too much of a rush...

Nitrogen narcosis (like divers might get) from high planetary atmospheric pressure and lots of nitrogen.

Actually, too much pressure will make any atmosphere deadly. CO2, Nitrogen, Oxygen - all of those gases will be deadly due to narcosis at not significantly higher pressures than on Earth. With Oxygen you have the added fun of greater flammability - lightning strikes starting fires even in wet/swampy conditions, for example - and O2 concentrations will cap out because of that (regional firestorms start more easily, burning up plants etc that create the oxygen and using it chemically, and O2 levels will go down to a level where that won't happen).

Humans are adapted to live in a relatively small range of oxygen pressures. Lower oxygen pressure causes health problems (even people acclimatized to high altitude living suffer from poorer health), and higher oxygen pressure causes lung damage and other long-term issues.

 

[Icosahedron]

I think you'd be struggling with using atmospheres. A pathogen is probably the way to go. If you've been to Planet A, there's no way you're disembarking on Planet B without an X month quarantine. I've seen similar situations in RL with Foot & Mouth and Yellow Fever.

As a sideline, different pressures could make for an interesting game twist. You enter a very high pressure world, but you have to leave it slowly because it will take you hours if not days to reduce hull pressure and avoid the bends, but if you hit space with your hull pressurised to planetary levels, it'll blow.
Don't rob a bank before you leave...

 

[fusor]

You enter a very high pressure world, but you have to leave it slowly because it will take you hours if not days to reduce hull pressure and avoid the bends, but if you hit space with your hull pressurised to planetary levels, it'll blow.
Don't rob a bank before you leave...

There are these things called "airlocks"...

 

[aramis]

I think you'd be struggling with using atmospheres. A pathogen is probably the way to go. If you've been to Planet A, there's no way you're disembarking on Planet B without an X month quarantine. I've seen similar situations in RL with Foot & Mouth and Yellow Fever.

As a sideline, different pressures could make for an interesting game twist. You enter a very high pressure world, but you have to leave it slowly because it will take you hours if not days to reduce hull pressure and avoid the bends, but if you hit space with your hull pressurised to planetary levels, it'll blow.
Don't rob a bank before you leave...

Any pressure sufficient to blow the hull will be essentially liquid and unbreathable anyway.

There are these things called "airlocks"...

It's much easier to go up in pressure than down...

And if the passengers are local, you need to decompress them slowly or they get the bends. 10 Atm with a nitrogen atmosphere should suffice.... it's a mining colony on a panthalassic world, and they dig ocean bottom. they keep the pressure up so they don't have to decompress after work (just like some long duration divers do), but then they spend a week or more in decompression.

Note tho: much past 10 ATM, and nitrogen becomes too much for the body to cope with.

 

[fusor]

Note tho: much past 10 ATM, and nitrogen becomes too much for the body to cope with.

Nitrogen narcosis actually starts to set in at lower pressures than 10 atm (about 4 atm pressure for earthlike air, IIRC, or around 3 atm partial N2 pressure).

Fact is, people aren't likely going to be walking around in high atm pressures (much above two or three atms) anyway - it's unlikely that that other gases in the atmosphere would still be breathable at high pressures. It's far easier to keep that atmosphere outside a sealed habitat than to live in it.

 

[aramis]

Nitrogen narcosis actually starts to set in at lower pressures than 10 atm (about 4 atm pressure for earthlike air, IIRC, or around 3 atm partial N2 pressure).

Fact is, people aren't likely going to be walking around in high atm pressures (much above two or three atms) anyway - it's unlikely that that other gases in the atmosphere would still be breathable at high pressures. It's far easier to keep that atmosphere outside a sealed habitat than to live in it.

Initial effects are at about 2 ATM for N2; past 10, it's not able to be coped with.

In any case, truth is that for deep divers, they do operate in up to 20 Atm on trimix (IIRC 2%/5%), with open moon pools, because it's easier to decompress once at the end of the up to 3 month long rotation, than a partial decompress daily and/or use of hardsuit.

 

[fusor]

Trimix is specially designed to not cause those problems at high pressures that I mentioned. The likelihood of a planet's high pressure atmosphere naturally having the right proportions of gases in such a way that narcosis doesn't kick in are somewhat low.

 

[Icosahedron]

There are these things called "airlocks"...

As Aramis says, airlocks won't prevent the bends unless you sit in them all week.

Any pressure sufficient to blow the hull will be essentially liquid and unbreathable anyway.

Depends how many atm hulls IYTU can stand...
Their design rating is around +1; can they stand +5, +10...?

Trimix is specially designed to not cause those problems at high pressures that I mentioned. The likelihood of a planet's high pressure atmosphere naturally having the right proportions of gases in such a way that narcosis doesn't kick in are somewhat low.

Could be terraformed that way, though. It might be easier to change the mix of an atmosphere than to remove huge quantities of it to reduce pressure.

 

[fusor]

Could be terraformed that way, though. It might be easier to change the mix of an atmosphere than to remove huge quantities of it to reduce pressure.

Terraforming is never the easier option.

It'll be easier to go to higher altitudes where the pressure is lower (think about it. To add gas to a dense atmosphere, you'd need a hell of a lot more of it than you would in a thinner atmosphere to raise the percentages).

It'll be even easier to pressurise the ships that are coming into land up to the higher local pressure. The crew can then decompress while they're in jump or in space after leaving the planet.

 

[BytePro]

Terraforming is never the easier option.

Never? That is an unsustainable answer. o:

This may, in fact, be the 'easier' option than situating millions or billions in higher altitudes, under domes with artificial atmos, or in suits, or majorly impacting interstellar commerce.

The amount of gas in a dense vs. less dense atmo is not likely to be an overriding issue when talking on a planet scale. Its the process to begin with and its scope that is the overriding general issue.

Changing a gas mixture on a global scale is a monumental task, but... the right combination of fauna, ocean catalyst, comet impacts and/or massive industrial processing could potentially do this in a few generations or much less. Especially if something unique to the world exists to make this more practical (natural source of 'entrapped' gas - released via impact/burning/EM radiation, bacteria, etc.)

After all - the Earth's atmo is 'engineered' by nature's own kitchen already, as far as we can tell.

 

[fusor]

Changing a gas mixture on a global scale is a monumental task, but... the right combination of fauna, ocean catalyst, comet impacts and/or massive industrial processing could potentially do this in a few generations or much less.

And a sealed habitat can be built in a few weeks or months, at far cheaper cost. Meanwhile, to terraform you need to spend a ridiculous amount of time, resources, and energy constructing atmosphere processors, moving comets, etc etc (and also, it's much harder to terraform thicker atmospheres than thin ones).

It is far easier to move a population to higher ground (or have them live in grav-supported floating cities, or have them live on higher ground to start with) than to change the environment to suit them. I can't see how you could argue otherwise; in one instance, you move your house, put on a space suit or live in a sealed environment, and in the other you change the environment for a whole planet. Which do you think produces more immediate results and is easier to do?

Try pitching the idea to an interstellar government or corporation : "we can either spend a few billion credits moving people to higher ground within a year, or we can spend a few trillion and spend 100 years terraforming the environment". Which do you think they'd go for?

Like I said, terraforming is never the easiest option. Any other method will achieve similar results (a habitable environment for colonists) far more quickly, more easily, and far cheaper (and more reliably) than modifying the environment would.

 

[E.D.Quibell]

Is it posible to move the population to higher ground, put them in sealed envirmonets etc and as a byproduct terraphorm the atmosphere at the same time?

Best regards,

Ewan

 

[BytePro]

...It is far easier to move a population to higher ground (or have them live in grav-supported floating cities, or have them live on higher ground to start with) than to change the environment to suit them. I can't see how you could argue otherwise; in one instance, you move your house, put on a space suit or live in a sealed environment, and in the other you change the environment for a whole planet. Which do you think produces more immediate results and is easier to do?

Uhm... sorry you can't see the possibilities... o:

Just because something is easy or cheap to do doesn't mean a thing will never be done nor that it shouldn't...

After all - making airplanes and spaceships was very time and resource consuming. Why do it - we already had ships and carts and feet!

Its silly to make assumptions on how 'expensive' it is to house a whole planet-wide civilization in artificial environments for generations rather than terraforming. That requires all kinds of assumptions about unknowns regarding future technologies, specific environments, and the 'costs'.

Nobody posted here that terraforming is cheap, or easy, or the 'best' solution in all cases. But, that sure doesn't mean it can 'never' be. Sorry, that is an unsustainable assertion.

And, likewise -

...it's much harder to terraform thicker atmospheres than thin ones.

Again, an absolute statement that is unsustainable.

A thicker atmosphere with the right chemical composition (something folks would look for in the vast numbers of planets), could provide a more readily decomposed mixture for 'terraforming'. Ex: a thin atmo with no O2 based compounds vs a denser one where the O2 is available in existing abundance, but bound in a readily separated form (CO2, O3, etc.). The process of separation often resulting in energy and chemicals useful for other processes.

Overall - thicker atmospheres may actually be best - everything may be there, just needing to be bound or chemically released more so natural (or easier artificial) methods can take effect.

Sure - by and large, terraforming (unless one assumes a nano-technology supported by a historical buildup sometime in the past to allow exponential replication along with transportation and reuse - or fantasy ) would not be common nor generally, at least in shorter timespans, economically wise. But, never. Nope, sorry, can't 'see' that.

 

[BytePro]

Is it posible to move the population to higher ground, put them in sealed envirmonets etc and as a byproduct terraphorm the atmosphere at the same time?

Best regards,

Ewan

An interesting question... possible?

Why not. How?

Well, one can actually 'levitate' items by ionizing atmospheric gases (this was done in the '70s and claimed as 'anti-gravity' by popular layman publications). Requires a good amount of energy (microwave, IIRC) - and a thicker atmo would be better. The process of doing such might change the chemical composition, releasing gases that then separate by mass or other reactions.

It would be quite complex and the energy and coverage extensive, but we are talking terraforming here anyway! A pretty outrageous solution to be sure, but so is going to the stars or trying to live as a civilization without an atmosphere! A prior post talked about domes for pressure - but bear in mind, our atmosphere doesn't just provide life required gases and pressure - it protects us from the radiation earth is bombarded with every moment.

Sealed environments could also cover the surface. Atmospheres which are dense due to planetary outgasing could conceivably be 'terraformed' in this way - especially if the regions aren't the entire surface of the planet.

Changing the temperature by changing the albedo and surface reflectivity can also have a huge effect. Color alone can do this. (Mind - we are talking massive amount of surface area here - even on 'small' planets).

Locations under oceans which interfere with global currents can have a very huge and relatively quick impact. Stop some of ours and we all suffer from O2 deprivation in pretty short order (this is actually the scariest 'global warming' scenario). This is because of the biomass of the oceans, btw, and their sensitivities to temperature.

There are a lot of 'conceivable' ways.

Mind, planets are huge, and most will probably be complex - so these 'simplistic' methods can be justified scientifically in a simple/enclosed system, that doesn't make this realistic - just not total fantasy. When talking about other planets we are 99% talking fiction and fantasy - no human has gone to any other planet in our solar system. Other than moon rocks and some comet tail fragments, I don't believe we have even brought back any other material! Most of our knowledge is Earth specific or indirect from optical measurements and a very few geology surveys (including bore samples and gas sensors) via probes and telescopes (and a bit from crap that has fallen from the sky!).

We've done some amazing and interesting things - but most of the marvels of the Universe are still a mystery to us!