'Alien' biosphere immune system effects

[Gondur]

Hello,

Suppose we humans traveled in a spacecraft to another Earth like planet with the same gravity and atmospheric composition as our own Earth.

Suppose we landed on the surface.

Suppose we opened the door of the craft, and walked onto the planet surface.

Suppose we did not wear a spacesuit - or any protection - aside from 'normal clothing' (jeans and t-shirt).

Suppose we inhale a couple of breaths.

Would we quickly collapse and die?

I assume that, because we (and our ancestors) - our DNA - has not evolved over millions of years within the biosphere of the alien world, our immune system has not developed an immunity to the millions of microbes floating in its atmosphere - equivalent microbes which here on Earth pose no threat to us - but are slightly different in their design and function on this new world that our immune system simply cannot recognise them and is vulnerable to them.

So, my point is, even if we found an Earth like world - with similar gravity, atmospheric composition etc - this similarly is only superficial - and its biosphere - especially life at the microbial level - would make moving and colonising this planet impossible - unless we develop immunity to its biosphere as we have done here on Earth.

Some thought is appreciated. Thanks.

 

[jim mcnamara]

Moved to general discussion. Most reasonable answers would involve guesswork, which is not okay in the Science forums.

 

[Drakkith]

Would we quickly collapse and die?

Not in the span of a few seconds to a few minutes, no. If would take time for any alien organisms to multiple enough to seriously harm us. At least a few hours probably, but I suppose a particular pathogen could produce a by-product that turns out to be a very potent nerve toxin or something. That might take less than an hour to kill us if the pathogen multiplied quickly enough.

I assume that, because we (and our ancestors) - our DNA - has not evolved over millions of years within the biosphere of the alien world, our immune system has not developed an immunity to the millions of microbes floating in its atmosphere - equivalent microbes which here on Earth pose no threat to us - but are slightly different in their design and function on this new world that our immune system simply cannot recognise them and is vulnerable to them.

Our immune systems have a variety of ways to recognize foreign microbes, viruses, etc. It's possible that our immune system would be able to recognize that these microbes are foreign and would be able to deal with them. Of course it's also possible that it wouldn't be able to. Or that it can recognize some of the microbes, but not all.

So, my point is, even if we found an Earth like world - with similar gravity, atmospheric composition etc - this similarly is only superficial - and its biosphere - especially life at the microbial level - would make moving and colonising this planet impossible - unless we develop immunity to its biosphere as we have done here on Earth.

That' certainly a possibility. Of course, the reverse is also true. It may be that the life on a particular planet is super-vulnerable to the microbes that normally live on and in our bodies.

 

[Evo]

First, no one would walk out of a spaceship onto an alien planet without protective gear and running tests first. Of course we can only test for known toxins. Doubtful anyone would keel over and die with their first unprotected breath, but yes, there could be things in the environment that could eventually cause illness and possibly death. As Jim said there is nothing else we can say here that's not a guess.

 

[sophiecentaur]

We are as likely to damage the new environment with our first exhalations, I would think.
We could easily extinguish a number of species but the effect might be some time after all our expedition members were dead.
At least the current Mars projects are taking a bit of care in this respect. So much so that the Mars X rover has a planned landing site that's not the best for the any actual life forms that may be found.
But explorers of all types have seldom had much regard for the ecology of the places they visit.

 

[berkeman]

Would we quickly collapse and die?

Similar to traveling between countries on Earth, it's important to get your shots first...

 

[sophiecentaur]

Similar to traveling between countries on Earth, it's important to get your shots first...

Europeans didn’t bother with that stuff and decimated (and worse) many native populations in the New World.