Thread: Composition of space and the potential that lies therein ?

Hello, i dont really have a good understanding of astronomy or cosmology, but i was wondering if space is really just a vacuum ? Is there absolutely nothing, or is there some gases ? Is there any such organism that can survive in space ? I remember reading about tardigrades and there tolerance to very low temperatures and a lack of oxygen ? Feedback would be much appreciated, cheers - Josh

No, space is not empty. It contains mostly atomic hydrogen gas with a density of about one particle per cubic centimetre. Other gases (next in line is CO = carbon monoxide) are present at a much smaller abundance, on average. The densities increase in active star forming regions and molecular clouds by a factor of typically 10000. Nevertheless, this is equivalent to a technical vacuum at a much lower pressure than can be achieved in any laboratory on earth.

Thanks for the feedback. Any idea about the Tardigrades and the potential for them to survive in space ?

Yes they've been tried in space ten days. One group sheltered in the vacuum, another group also exposed to solar radiation. Some animals from both groups survived and reproduced successfully, although sunlight brought a few out of hibernation and those died several days into the experiment. They wouldn't have been happy campers. But I wonder how long they'd have lived (awake) in space with a very rude partial habitat, like a frozen broccoli.

As Dishmaster pointed out, there are some atoms in space, material from the solar wind. Extremeophile bacteria has survived in a vacuum, in radiation, in heat and cold, strong acids and alkalies, deep underground away from sunlight as well as periods of dormancy of tens of thousands of years, etc. It is possible they could survive journeys through space.

Originally Posted by Cyberia

As Dishmaster pointed out, there are some atoms in space, material from the solar wind. Extremeophile bacteria has survived in a vacuum, in radiation, in heat and cold, strong acids and alkalies, deep underground away from sunlight as well as periods of dormancy of tens of thousands of years, etc. It is possible they could survive journeys through space.

As a microbiologist who has had some contact with astrobiologist I remain skeptical of theories of panspermia. The main problem is that extremophiles tend to be specialized to one extreme, while traversing space would require the organism to survive extreme radiation, cold, and heat. Hyperthermophiles can survive temperatures around 120 C at the bottom of the ocean, but they die under 70 C. They would then also have to conveniently land in a suitable habitat on another planet.

Life on Earth has long ago settled into steady niches. Possibly on a younger planet life might be willing to adapt to a number of much more hostile conditions and if blasted into space from a giant volcano or asteroid strike, might survive a lot of years in space? One record holder:

Scientists have brought a newly-discovered bug back to life after more than 120,000 years in hibernation. It raises hopes that dormant life might be revived on Mars. The tiny purple microbe, dubbed called Herminiimonas glaciei, lay trapped beneath nearly two miles of ice in Greenland. It took 11 months to revive it by gently warming it in an incubator. Finally the bug sprang back to life and began producing fresh colonies of purple brown bacteria.

http://www.scientificamerican.com/ar...-years-2009-06


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Originally Posted by mrjoshers

Hello, i dont really have a good understanding of astronomy or cosmology, but i was wondering if space is really just a vacuum ? Is there absolutely nothing, or is there some gases ? Is there any such organism that can survive in space ? I remember reading about tardigrades and there tolerance to very low temperatures and a lack of oxygen ? Feedback would be much appreciated, cheers - Josh

When it comes to science, I form my own opinions.

I prefer precise definitions. So I consider space to be the void (vacuum) between objects.
Its standard is the 'METER' and this dimension is on display in France that is a bar of platinum one 'official' meter long.
So this dimension does not expand or contract. Ha ha.

Regarding life? Probably the first source of life on our planet is the plant seeds.
Seeds can withstand temperatures much colder than the animal eggs such as 'STEM' cells I think(?).

Liquid nitrogen has a temperature of 70K. So living forms can survive at that temperature in a dormant state.
Since they are frozen solid in this state, how much further can they go down into a lower frozen state? That is the big question?

Cosmo

Originally Posted by Cosmo

Its standard is the 'METER' and this dimension is on display in France that is a bar of platinum one 'official' meter long.

This has been the definition for a while. It was replaced by a different definition now using the speed of light in vacuum as the reference.
http://en.wikipedia.org/wiki/Metre

Originally Posted by i_feel_tiredsleepy

Originally Posted by Cyberia

As Dishmaster pointed out, there are some atoms in space, material from the solar wind. Extremeophile bacteria has survived in a vacuum, in radiation, in heat and cold, strong acids and alkalies, deep underground away from sunlight as well as periods of dormancy of tens of thousands of years, etc. It is possible they could survive journeys through space.

As a microbiologist who has had some contact with astrobiologist I remain skeptical of theories of panspermia. The main problem is that extremophiles tend to be specialized to one extreme, while traversing space would require the organism to survive extreme radiation, cold, and heat. Hyperthermophiles can survive temperatures around 120 C at the bottom of the ocean, but they die under 70 C. They would then also have to conveniently land in a suitable habitat on another planet.

True. As a paleontoligist I agree.

The concept of 'extremophile' is a human centric one. Organisms live in the 'just right' environment for their own reproduction. A desert is 'hot' or the Arctic 'cold' only as subjective human descriptions.

And if an organism ever did make it from one planet to another then everyone of it's life sytems would need to be satisfied to survive and then much more precise conditions needed for reproduction.

Put a human in a spacecraft to protect him and then land randomly on some planet or moon in our solar system...jump out naked and you'd be dead...dead because of several variables...and forget reproduction. Extend this to the nearest thousand stars and it is still unlikely that all the variables would be present to support what we call an extemophile or a human. Every organism on earth has had 4 billion years adapting via natural selection to precise conditions.

Originally Posted by Cyberia

Life on Earth has long ago settled into steady niches. Possibly on a younger planet life might be willing to adapt to a number of much more hostile conditions and if blasted into space from a giant volcano or asteroid strike, might survive a lot of years in space? One record holder:

Natural selection is unlikely to produce such a result. There are cost associated with any adaptation. Organisms don't settle into steady niches for the hell of it, but because selection strongly favours it.

Extremophiles may exist on other planets where we wouldn't expect life, but I doubt any have travelled to Earth.

Originally Posted by Cosmo

[
Regarding life? Probably the first source of life on our planet is the plant seeds.
Seeds can withstand temperatures much colder than the animal eggs such as 'STEM' cells I think(?).

Huh?

Plants are definitely not the oldest organisms on Earth. It is generally accepted that eukaryotes evolved from the symbiotic association of an archaea with a baterium. This is supported by the fact that the mitochondria resembles a bacterium in structure and has it's own genome.

There is also the fact that there are archaea and bacteria that are more genetically different from each other than you or I are from a turnip. This suggests a much early evolutionary divergence.