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Xibalba
2012-Feb-13, 01:01 AM
Hi.
Russians have recently drilled all the way into a subantarctic lake who's been isolated for at least 15 million years.

Are you excited about this? Honestly I can't wait!

What are your thoughts on the subjects? Any speculations on what they might find?

How can this change our view of xenobiology?

transreality
2012-Feb-13, 02:22 AM
Putin seemed excited that he could drink water that was witnessed by the dinosaurs, but they died 65 million years ago, so no risk of that.

Blackhole
2012-Feb-13, 03:43 AM
I'm excited because it gives a little more hope to the possibility of on-Earth Life existing within our Solar system, and in particular Europa and Enceladus.

Substantia Innominata
2012-Feb-14, 05:55 PM
Putin seemed excited that he could drink water that was witnessed by the dinosaurs, but they died 65 million years ago, so no risk of that.

Hehe, I read the same 'story' a few days ago in a local newspaper. Back then I was actually flabbergasted, because from what I knew by then, it hadn't even been clear, or at least officially confirmed by the Russian side, that the drill had indeed already succeeded and a water sample out of the lake been taken. Let alone said sample brought back to Russia?! I don't know, it just seemed quite fast to me.. :confused: Only a few days before that there was still confusion as to whether the Russians had really done it, and reached the lake. Not that I'm much in a position to criticize and perhaps it really comes down to a bit of tardy information for my part, though considering that nothing but this Putin-news story is the way I learned about the accomplishment, a little more transparency of the proceedings would've been nice.

Putin himself, by the way, was of course rather joking as he queried Russia's Natural Resource Minister, Yury Trutnev (who also delivered the water sample to him), whether the latter had already 'have a go' at the sample (i. e. drank from it).. and then added that it might have been funny, considering 'Trutnev and the dinosaurs' sipping the selfsame water.

Apart from transreality's own clarification concerning the dinosaurs, it remains fairly unclear to me where the these days often printed number of '(one) million years' old water comes from. Or on what exactly that is based. The sample itself has not been analyzed yet. And from all I know the only thing that could be taken for certain is that the ice sheet just above Lake Vostok has been dated to at least ~420,000 yrs. Which tells you not much about the lake, however, since that could still be way older--and it could unfortunately also be way younger, for example in the case of there being (hitherto undetected) cracks, crevices, or even a downright system of subterranean tunnels, connecting the lake to other bodies of fresh water and therefore leading to (whether sporadic, seasonal, or actually permanent) exchange of substance.


I'm excited because it gives a little more hope to the possibility of on-Earth Life existing within our Solar system, and in particular Europa and Enceladus.

What do you mean by 'on-Earth' life?

DonM435
2012-Feb-14, 08:18 PM
Bah! Russians don't drink water. Just vodka. You do trust General Jack Ripper, right?
;)

kzb
2012-Feb-15, 05:43 PM
The mean residence time of the water could be as low as 13,300y. This is because the ice sheet covering it is moving, and water melts and freezes at the water ice/boundary.

This is from Wikipedia, and so much I understand. However I can't understand where all the oxygen comes from. Can anyone clarify this?

Quote:
Lake Vostok is an oligotrophic extreme environment, one that is expected to be supersaturated with nitrogen and oxygen,[32][33] measuring 2.5 liters of nitrogen and oxygen per 1 kilogram (2.2 lb) of water,[34] that is 50 times higher than those typically found in ordinary freshwater lakes on Earth.

http://en.wikipedia.org/wiki/Lake_Vostok

Blackhole
2012-Feb-18, 12:48 AM
What do you mean by 'on-Earth' life?

Sorry that was a typo, I meant to say non-Earth based life.

moozoo
2012-Feb-21, 10:13 AM
If the sample was “twice as pure as double-distilled water.” doesn't that rule out hydrothermal vents somewhere at the bottom since I assume these would spew out minerals into the water.

Xibalba
2012-Feb-26, 01:43 AM
The mean residence time of the water could be as low as 13,300y. This is because the ice sheet covering it is moving, and water melts and freezes at the water ice/boundary.

It doesn't matter, since the organism possibly living in the lake cannot escape, nor could organisms from out of the lake enter this extreme environment.

Some archeae or bacteriae might live in this lake, and I don't suppose they could survive outside this unlikely environment. I don't think any "predator" or rapid animal inhabits this lake, since the energy input is quite low, as I see it. No light = no photosynthesis. Archeae or bacteriae would have to take energy from chemical processes instead of transforming the sun's rays. Those would be the "base" of the food chain, and if they are in great enough quantities, higher animals might have survived... maybe?

kzb
2012-Mar-06, 01:17 PM
It doesn't matter, since the organism possibly living in the lake cannot escape, nor could organisms from out of the lake enter this extreme environment.

Some archeae or bacteriae might live in this lake, and I don't suppose they could survive outside this unlikely environment. I don't think any "predator" or rapid animal inhabits this lake, since the energy input is quite low, as I see it. No light = no photosynthesis. Archeae or bacteriae would have to take energy from chemical processes instead of transforming the sun's rays. Those would be the "base" of the food chain, and if they are in great enough quantities, higher animals might have survived... maybe?

Sorry, I was answering the point about drinking water as old as the dinosaurs. If you have a mean residence time of 13,300 years the dilution factor for the dinosaur water would be enormous.

As for your second point, I repeat my earlier question: where is all the oxygen coming from? If there really is this high free oxygen pressure, then any remaining organic matter, or organic matter transported in from the base of the moving ice sheet, will be food for microorganisms, which in turn could be food for higher life forms.

Problem is, no-one can tell me where this oxygen comes from. I'd have thought it would be a smelly, anoxic, sulphurous pit, but it seems not going by Wikipedia.

Selfsim
2012-Mar-08, 01:33 AM
As for your second point, I repeat my earlier question: where is all the oxygen coming from? If there really is this high free oxygen pressure, then any remaining organic matter, or organic matter transported in from the base of the moving ice sheet, will be food for microorganisms, which in turn could be food for higher life forms.

Problem is, no-one can tell me where this oxygen comes from. I'd have thought it would be a smelly, anoxic, sulphurous pit, but it seems not going by Wikipedia.Hi kzb;
This is a great question .. (its really fired me up to research more about the entire Lake Vostok issue). Thank you for raising it.

In snooping around, I found this BBC Horizon Documentary: The Lost World of Lake Vostok. (http://www.youtube.com/watch?v=APaBqRp27zU) It goes through the history of scientific developments and thinking about the geology etc. Whilst it doesn't explicitly address the presence of saturated oxygen issue, it seems fairly clear that Lake Vostok is not thought to have been completely isolated throughout its entire history. Oxygenated water, which may have orginally been abundant, could quite easily have been sealed in, when the lake froze over (after its formation, which was about 30 million years ago).

Another approach, which might be more revealing, would be to contemplate the opposite question. Ie: "Why would there not be oxygen in Vostok's deep water ?"

It seems the Vostok region still exhibits geological activity today, also.

The documentary also brings the Europa analogy into the picture and NASA's probe/robot ideas, as well.

For my 2 cents worth, my view is that very few (if any) of these extreme environments, have ever been truly isolated from either the atmosphere, surface water flows, or by biologically impenetrable membranes.

Other Solar System planetary environments however, are way more likely to have been isolated, for way longer periods.

Regards

kzb
2012-Mar-08, 12:50 PM
Selfsim wrote:
"Why would there not be oxygen in Vostok's deep water ?"

If you go to a muddy river estuary and dig down in the mud only a few cm, you will see a colour change in the mud, from brown/tan near the surface to green/black a few cm down. This colour boundary marks where iron is oxidised to Fe(III) near the surface and reduced to Fe(II) further down. This boundary can also be seen in soils in some areas.

It's also fairly commonplace for bodies of water, with free access to atmospheric oxygen at their surfaces, to become anoxic.

Free oxygen is an energy-rich fuel for oxidising organic matter and reduced sulphur species, so good that it gets used up first.

So any free oxygen that got sealed in originally should have been used in oxidising residual organic matter. The only way this would not happen is if there was very little organic matter to begin with. Or maybe the water is so toxic that no microbial action is possible.

If microbial action IS possible, any reduced sulphur species from volcanic sources would be used as fuel and consume any free oxygen. I don't think volcanic sources produce net free oxygen.

So to be honest the mystery continues. I can't see why this lake should be super-saturated in free oxygen.

Selfsim
2012-Mar-09, 11:51 PM
Why would there not be oxygen in Vostok's deep water ?

If you go to a muddy river estuary and dig down in the mud only a few cm, you will see a colour change in the mud, from brown/tan near the surface to green/black a few cm down. This colour boundary marks where iron is oxidised to Fe(III) near the surface and reduced to Fe(II) further down. This boundary can also be seen in soils in some areas.

It's also fairly commonplace for bodies of water, with free access to atmospheric oxygen at their surfaces, to become anoxic.Sure .. but Vostok is not a typical freshwater lake, eh ?
Clearly, Vostok has little/no access to recent atmospheric oxygen, although, isn't it also possible that oxygenated water is inflowing from elsewhere in the region ? What about the clathrates known to form under such conditions as Vostok's ?
What physical assumptions set expectations that such a process, resulting in an anoxic environment, would apply in Vostok ? How does 'commonplace' apply to Vostok ?


Free oxygen is an energy-rich fuel for oxidising organic matter and reduced sulphur species, so good that it gets used up first.

So any free oxygen that got sealed in originally should have been used in oxidising residual organic matter. The only way this would not happen is if there was very little organic matter to begin with. Or maybe the water is so toxic that no microbial action is possible.Perhaps the oxygen was not initially readily accessible to the hypothesised organic matter ?


If microbial action IS possible, any reduced sulphur species from volcanic sources would be used as fuel and consume any free oxygen. I don't think volcanic sources produce net free oxygen.This would seem to require the assumption of (i) the presence of a particular type of organism defined by this metabolic process, and (ii) that volcanic sources were feeding sulphur based chemicals into the lake ?


So to be honest the mystery continues. I can't see why this lake should be super-saturated in free oxygen.Its known to be an extreme environment. Clearly, there are likely to be processes going on, which we probably haven't encountered before.

To me, this is a clear case of saying little, and investigating a lot.
Speculating from past knowledge is likely to lead to paradoxes created by unstated speculative assumptions. Thank goodness the empirical testing process can be designed to remove speculative assumptions and prevent them from interfering with the observations/findings.

Regards

Colin Robinson
2012-Mar-10, 07:03 AM
Sorry, I was answering the point about drinking water as old as the dinosaurs. If you have a mean residence time of 13,300 years the dilution factor for the dinosaur water would be enormous.

As for your second point, I repeat my earlier question: where is all the oxygen coming from? If there really is this high free oxygen pressure, then any remaining organic matter, or organic matter transported in from the base of the moving ice sheet, will be food for microorganisms, which in turn could be food for higher life forms.

Problem is, no-one can tell me where this oxygen comes from. I'd have thought it would be a smelly, anoxic, sulphurous pit, but it seems not going by Wikipedia.

Perhaps the key word in the passage you quoted is "oligotrophic", meaning low in nutrients, i.e. very little organic matter?

If nutrients were abundant, then yes, microbes would consume the oxygen and the nutrients until the lake became anoxic and smelly. But low nutrient levels mean microbial activity is very limited, because there's not much for the poor things to eat.

O2 levels can remain high, not because there is new oxygen coming in, but because there is very little happening to reduce the original inventory of O2?

Selfsim
2013-Mar-08, 02:24 AM
So, finally RIA Novosti announces … (warning .. incomplete (and largely inadequate) reporting follows):

Russia finds 'new bacteria' in Antarctic lake (http://phys.org/news/2013-03-russia-bacteria-antarctic-lake.html)


"After putting aside all possible elements of contamination, DNA was found that did not coincide with any of the well-known types in the global database," he said.

"We are calling this life form unclassified and unidentified," he added.

Bulat said that the interest surrounded one particular form of bacteria whose DNA was less than 86 percent similar to previously existing forms.

"In terms of work with DNA this is basically zero. A level of 90 percent usually means that the organism is unknown."

He said it was not even possible to find the genetic descendants of the bacteria.
Hmm … more information needed … has anyone seen some better quality info on this report yet?

Selfsim
2013-Mar-09, 05:45 AM
So more information at NewScientist, here. (http://www.newscientist.com/article/dn23253-mystery-bug-found-in-antarcticas-lake-vostok.html)

Pearce has studied samples from Lake Hodgson, which lies beneath just a few metres of ice in west Antarctica. He says 25 per cent of the genetic sequences he has found do not match anything found in DNA databases. So on its own, having an unusual DNA sequence does not prove that the Vostok bacterium belongs to a new group. There's a long list of systematic tests that will need to be carried out in order to prove that.
The results must also be independently replicated, says Martin Siegert of the University of Bristol, UK, who led an unsuccessful attempt to drill into another Antarctic lake - Ellsworth - last year.
...
If the bacterium does belong to a new group, it will quickly come under scrutiny. "The next question is, where does it come from?" says Siegert.Interesting ... notice the underlined bit. Clearly, its life as we know it - ie: DNA, (albeit unusual), based bacterium. Would this be similar to what exo-life searchers are presently expecting might exist elsewhere in the universe? The classification process required in order to more fully come to grips with what it actually is, appears to be quite complex.

Is this an analog example of the process we'd have to follow if a similar discovery is found on some local planet/moon?
If so, can the needed technology be reasonably integrated onto a robotic probe? (Or does it call for humans to carry out such complex diagnosis?)
Can such diagnosis be done remotely over light-year distances?

galacsi
2013-Mar-09, 09:38 AM
Selfsim wrote:
"Why would there not be oxygen in Vostok's deep water ?"

. . . .
So to be honest the mystery continues. I can't see why this lake should be super-saturated in free oxygen.

What I know is that glacial ice contains some air because it is made by compacting snow which is mostly air.

From Wikipedia :


Under the pressure of the layers of ice and snow above it, this granular ice fuses into denser and denser firn.
Over a period of years, layers of firn undergo further compaction and become glacial ice.
Glacier ice is slightly less dense than ice formed from frozen water because it contains tiny trapped air bubbles.

Selfsim
2013-Mar-10, 12:03 AM
And again more confusion reported this morning's news:

Russia admits no new life form found in Antarctic lake (http://phys.org/news/2013-03-russia-life-antarctic-lake.html)


But the head of the genetics laboratory at the same institute said on Saturday that the strange life forms were in fact nothing but contaminants. "We found certain specimen, although not many. All of them were contaminants" that were brought there by the lab during research, Vladimir Korolyov told the Interfax news agency.

"That is why we cannot say that previously-unknown life was found," he said.

Its hard to know what they are reporting :confused:

Jens
2013-Mar-11, 01:56 AM
Interesting ... notice the underlined bit. Clearly, its life as we know it - ie: DNA, (albeit unusual), based bacterium. Would this be similar to what exo-life searchers are presently expecting might exist elsewhere in the universe?

I sort of doubt it, because I think when they say "unusual" here they mean "normal DNA structure, but in sequences that are not seen in known organisms." In the case of exo-life, unless it is related to us through panspermia, or unless there is something inherently natural about the four bases that are used in earth DNA, it might be a completely different structure.