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Bacteria on the outside of the International Space Station

independent.co.uk

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Re: Bacteria on the outside of the International Space Station

#41

Post by sitkack »

api wrote: post #5
carapace wrote: post #3

Earlier quoted context omitted.

I'd love for this story to be true but it's almost certainly not, the bacteria must be terrestrial. Cf. https://en.wikipedia.org/wiki/Tersicoccus_phoenicis "It has only been found in two spacecraft assembly clean room facilities..." Maybe it's not T. phoenicis but it's not ET. (However, if it somehow turns out to be alien, that seems to be to imply that interstellar space must be swarming with bacteria, yes? For the…

You're probably right in this case, but as for the last part consider that the Earth is a gravity well and the ISS has been in space for a very long time. Earth is going to draw in particles and the ISS has had plenty of time to catch them.

Then shouldn't the Earth Moon Lagrange points have bacteria in them them as well? Or Geosync satellites? Plenty of places to look.

Re: Bacteria on the outside of the International Space Station

#42

Post by johnhenry »

greggarious wrote: post #37
Sir_Cmpwn wrote: post #28

Earlier quoted context omitted.

Actually, they ship it down to Earth during the resupply missions.

My bad, I may be crossing some wires and thinking of certain trains.

I am by no means an expert, but I linked to an article above that indicates that you were right all along.

Specifically "... is ejected from the station and burns ..." though there isn't much else to support for this.

Re: Bacteria on the outside of the International Space Station

#43

Post by AnimalMuppet »

JoeAltmaier wrote: post #33
antonvs wrote: post #31

Earlier quoted context omitted.

Is is possible? Yes. Is it likely compared to the alternative? No. Comets are theorized to have brought us water from within the solar system, so the comparison doesn't really apply unless life evolved in our solar system but somewhere other than Earth. Here's some of what has to happen for life to cross naturally between planets in different solar systems: 0. Life evolves somewhere else 1. Somehow, some of that life…

Bad conclusion. There are billions of 'other planets' and only one Earth. You'd have to add up the marginal probabilities of all the other scenarios, to compare with just the Earth scenario.

But of those billions of other planets, as they get further and further away, the probability of an asteroid from them finding Earth goes down. So does the probability of life on the asteroid surviving the trip.

I think that the number of planets within a distance R is O(R^2), but the probability of an asteroid from such a planet reaching us is O(1/R^2). But if the probability of life on the asteroid surviving the trip decreases with a longer trip, the net effect is probably that the further-away planets contribute little to the probability of life reaching us in this way.

Re: Bacteria on the outside of the International Space Station

#44

Post by QAPereo »

yosito wrote: post #7

Sounds slightly surprising, but the exterior of the ISS is not a sterile environment. There are thousands of ways terrestrial bacteria could have ended up there. I guess the interesting thing is that the bacteria seem to be able to survive the extreme environment. But that's hardly a new discovery about bacteria.

Remember that human feces ended up in orbit, although not from recent sources.

Re: Bacteria on the outside of the International Space Station

#45

Post by antonvs »

JoeAltmaier wrote: post #33
antonvs wrote: post #31

Earlier quoted context omitted.

Is is possible? Yes. Is it likely compared to the alternative? No. Comets are theorized to have brought us water from within the solar system, so the comparison doesn't really apply unless life evolved in our solar system but somewhere other than Earth. Here's some of what has to happen for life to cross naturally between planets in different solar systems: 0. Life evolves somewhere else 1. Somehow, some of that life…

Bad conclusion. There are billions of 'other planets' and only one Earth. You'd have to add up the marginal probabilities of all the other scenarios, to compare with just the Earth scenario.

> You'd have to add up the marginal probabilities of all the other scenarios, to compare with just the Earth scenario.

There aren't even close to billions of other planets that could have been candidates for sending a life-bearing asteroid to Earth. Some of the restrictions are:

1. A planet capable of having developed life.

2. A planet close enough for an asteroid from it (I have trouble typing that because it's such an unlikely scenario) to have reached Earth around the time that life on Earth began. That was ~4 billion years ago, which seems like a lot, but consider that if the recently spotted asteroid 1I/2017 U1 had come direct to us from Proxima Centauri, the closest star, it would have taken at least 48,000 years to get here. That puts a limit on candidate sources of less than 100 times the distance to Proxima, and limits the number of star systems to ~2 million.

Even if you multiply the probabilities in question by a factor of 1e6 to 1e7, it's not going to change the conclusion.

Re: Bacteria on the outside of the International Space Station

#46

Post by Spare_account »

Sir_Cmpwn wrote: post #28
greggarious wrote: post #25

Doesn't the ISS blast human excrement out into space? Maybe that explains the bacteria ¯\_(ツ)_/¯

Actually, they ship it down to Earth during the resupply missions.

I'm getting conflicting information from NASA on this.

According to the first link (PDF, sorry), waste is disposed of in re-entry craft.

But according to the second link, it's ejected to burn up in the atmosphere.

https://www.nasa.gov/sites/default/files/files/issrdc_2013-0...

https://www.nasa.gov/mission_pages/station/research/news/inf...

Re: Bacteria on the outside of the International Space Station

#47

Post by douglaswlance »

Sir_Cmpwn wrote: post #9

The suggestion that the bacteria is extraterrestrial in origin is absolutely ridiculous. Much, much, much more research is necessary before such a claim can be made. The speculation on Shkaplerov's part is hugely unprofessional.

That's how you get the clicks bro.

Re: Bacteria on the outside of the International Space Station

#48

Post by wil421 »

antonvs wrote: post #31
wil421 wrote: post #24

Earlier quoted context omitted.

If comets supposedly brought us water why not life? I just read an article yesterday about an asteroid from another solar system[1]. Maybe there was a Prometheus-esque comet with some single celled life in it. [1] http://time.com/5033026/mysterious-object-confirmed-another-...

Is is possible? Yes. Is it likely compared to the alternative? No. Comets are theorized to have brought us water from within the solar system, so the comparison doesn't really apply unless life evolved in our solar system but somewhere other than Earth. Here's some of what has to happen for life to cross naturally between planets in different solar systems: 0. Life evolves somewhere else 1. Somehow, some of that life…

How is your list any more remarkable than life starting on Earth in the first place?

What’s the probability of adding water and heat to a planet then waiting a few billion years for life? I hope we can send some probes to Saturns moons and find out. Even Mars could have a trace of life in the dirt.

Re: Bacteria on the outside of the International Space Station

#49

Post by reubenswartz »

avian wrote: post #32
reubenswartz wrote: post #16

Earlier quoted context omitted.

There are plausible theories about how life arose on Earth. If you want to assume it came from somewhere else, you either have to invoke some kind of magic, or assume it happened somewhat along the lines that it would have done on Earth, then arrived somehow. It just kicks the can down the road without solving anything, IMO.

> It just kicks the can down the road without solving anything Panspermia is an attempt to explain one inconsistency in our observations so far: it appears that life spontaneously emerging from inorganics is hugely unlikely. On other hand, geological records show that life appeared on Earth very soon after it became viable. If life on Earth originated somewhere else, then this discrepancy can be made to disappear. Fo…

It's certainly a valid hypothesis. And stronger (any?) evidence for possible life on Mars or Venus would possibly support this.

With a sample size of 1, and loose record-keeping from ~4B years ago, it's hard to tell, but we don't really know if it took life 1 day or 500M years to evolve once it was chemically/geologically viable. We do know that life was very primitive for > 1B years (not even eukaryotic, let alone multicellular).

We also know that space isn't teaming with little biologically active spores from other worlds (unless it is and the government is covering it up, of course), which suggests that in the vastness of space, life doesn't really hitch rides on asteroids or comets and colonize the galaxy accidentally. And if some beings were doing this on purpose, why not send more advanced life forms or robots?

Re: Bacteria on the outside of the International Space Station

#50

Post by BeefySwain »

QAPereo wrote: post #44
yosito wrote: post #7

Sounds slightly surprising, but the exterior of the ISS is not a sterile environment. There are thousands of ways terrestrial bacteria could have ended up there. I guess the interesting thing is that the bacteria seem to be able to survive the extreme environment. But that's hardly a new discovery about bacteria.

Remember that human feces ended up in orbit, although not from recent sources.

That sounds interesting. Do you have more info on that? A source perhaps?
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