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Strange Bacteria Sustains Itself Without Sunlight
Posted by
CowboyNeal
on Fri Oct 20, 2006 05:12 AM
from the deep-dark-places dept.
from the deep-dark-places dept.
Hahnsoo writes "A colony of bacteria found 2.8 kilometers below the Earth's surface in a South African gold mine is able to sustain itself without energy from the Sun. While sub-surface colonies of microorganisms utilizing sulfur (mostly near deep sea hydrothermal vents) is not new, this particular colony is unusual. The colony does it by relying on radioactive uranium to split water into hydrogen gas. Thus, instead of solar energy and photosynthesis, this species relies on radioactive materials and sulfur/hydrogen to facilitate its energy needs. There is some speculation about life on other planets in the article as well."
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Strange slashdotter sustained without sunlight (Score:5, Funny)
We manage to sustain ourselves using colonies of microorganisms utilising twinkie bars and coke (mostly near mom's fridge).
We rely on radiation from our CRT monitors and heat from mom's washing machine to act as a catalyst converting the food bars into into methane gas. Thus instead of having a nice basement, its a desolate wasteland where noone would dare to tread.
There is some speculation about how life evolved inside such places (or should that be devolved).
Re:Strange slashdotter sustained without sunlight (Score:5, Funny)
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Re:Strange slashdotter sustained without sunlight (Score:5, Funny)
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Re:Strange slashdotter sustained without sunlight (Score:5, Funny)
Sadly, more true than many would realize...
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Re:Strange slashdotter sustained without sunlight (Score:5, Funny)
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prior art (Score:5, Funny)
Why is this news? Clearly you've never been to a Linux User's Group meeting.
Hindenburg disaster? (Score:5, Informative)
"Hydrogen gas is highly energetic if it reacts with oxygen or other oxidants like sulfate, as the Hindenburg disaster demonstrated."
What's the point of adding these sorts of comments? It's it widely understood that the actual flames captured on the footage was in fact from the covering and paint of the Hindenburg, not the hydrogen which would have very rapidly dissapated in the first place?
Re:Hindenburg disaster? (Score:5, Interesting)
That's partly true. The burning covering provided the soot that was able to glow and make the flames visible. Hydrogen flames are almost invisible.
However, urban legends about the extreme flammability of the doping notwithstanding, there is NO WAY a vessel the size of the Titanic could be vaporized in 30 seconds, throwing a mushroom cloud hundreds of feet into the air, unless the reaction was driven mainly by the burning hydrogen gas. The gas did dissipate quickly; it just happened to be burning as it did.
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Re:So now we have (Score:5, Funny)
If Steve Irwin were still alive, he would capture it, thoroughly describe it to the viewers at home, shove his thumb up it's butt, and then say "Crikey, its a naughty boy!"
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Re:Forgive my ignorance (Score:5, Informative)
Yes, these are natural uranium ores in South Africa.
The radioactive half-life of uranium [wikipedia.org] is in the order of 100 millions of years for the two common isotopes of uranium that the radioactivity of itself is not very significant.
Radioactive materials used for power-production from radioactive decay itself (see radioisotope thermoelectric generator [wikipedia.org]) use radioisotopes with half-lives of tens to hundreds of years.
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Answers (Score:5, Informative)
(b) It's not practical to use its radioactivity as a power source, however, because it's only mildly radioactive in the natural state; said another way, it's not appreciably warm, so the amount of heat given off of natural uranium due to its radioactivity is negligible.
(c) Most (nearly all) human-generated nuclear waste has the same answer as (b); of that that is appreciably warm, there's too little of it to be useful as a power source.
(d) You got it.
Note that the bacteria do not use radioactivity directly, but rather use hydrogen from their environment, made from decomposing water exposed to radioactivity, as an energy source. Again from TFA: "This fracture water contained hydrocarbons and hydrogen not likely to have been created through biological processes, but rather from decomposition of water exposed to radiation from uranium-bearing rocks."
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Re:Forgive my ignorance (Score:5, Informative)
It is not viable for large scale power, since you would need so much Uranium and other material to get megawatts of power out of it. I think they can make them out of Plutonium too (which is not naturally occurring)
Nuclear "waste" is already converted back into fissile material, if material is radioactively hot it is pretty easy to extract energy from. It's the stuff that is slightly radioactive with a long half life that is not very useful and becomes low grade waste.
Please explain what is "creepy" about fission? Seems like a better deal than burning oil. What is the point of having an electric car if you're just going to charge it by burning coal and oil?
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Re:Forgive my ignorance (Score:5, Interesting)
Electric motors are much more efficient.
Electricity can come from non-polluting sources.
The cost of electricity hasn't risen 300% in six years.
Pollution from a few sources is more easily managed and disperses less than from millions of ground level sources.
Electric cars are simpler mechanically, more reliable and easier to repair.
Electric cars accelerate faster and can use regenerative braking.
Existing range limitations can be overcome with improved battery chemistry.
see www.whokilledtheelectriccar.com to see why we're not driving them and why all the EV1's were destroyed.
Offtopic but you did ask.
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Re:Forgive my ignorance (Score:5, Insightful)
You name three accidents. Chernobyl was admittedly a disaster, but the other two didn't even result in any injuries. So, that's like a grand total of one nuclear disaster. Now, how many people has coal power killed? Hundreds of thousands of miners, perhaps millions more who have suffered from the pollution and - yes - radioactivity released into the atmosphere by coal plants.
Coal power is responsible for more cancer than any nuclear accident ever, including Chernobyl. Think about it.
Thirdly, terrorism. You don't get coal-fired suicide bombers.
You don't get fission suicide bombers either, so what the fuck is your point supposed to be?
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Re:Forgive my ignorance (Score:5, Insightful)
Chernobyl, Windscale, Three Mile Island.
Chernobyl was a very serious incident. WHO attributed 56 direct deaths and possibly as many as extra 4000-6000 cancer deaths in the long term. (source 1) [bbc.co.uk], (source 2) [nature.com]. However, you can't compare the Chernobyl reactor to western reactors of that day and age and certainly not to new types of reactors with passive safety. Three Mile Island is considered to be worlds' second worst nuclear accident. The death toll? 0. Compare that to the thousands of people that die in Chinese coal mines every year. (source) [chinadaily.com.cn]
We're told that current nuclear plants are safe, and not like the ones that exploded or went up in flames. At the time the plants which are now acknowledged to be dangerous were being constructed, the public were also told that they were completely safe. The public can be forgiven for not believing that an industry with a history of serial lies on safety is now both safe and
truthful about it for once.
They ARE safe, even the ones that were being built back then. There is no such thing as 100% safety but the safety record of western nuclear power plants is way better than any other industry. Bhopal anyone?
Also, I don't suppose they were actually intending to have any accidents, or for some of the radioactive leaks - though BNFL's own propaganda admits they deliberately discharged nuclear waste into the sea. Humans make mistakes, which is another reason nuclear isn't trusted.
That's why we need to keep investing ways to make better use of nuclear fuel. A lot of promising research has been done in that area, like the Integral Fast Reactor [wikipedia.org], which by the way is even safer than contempary reactors.
Thirdly, terrorism. You don't get coal-fired suicide bombers.
It's a lot easier to blow up a refinery, which would cause vastly more damage. Containment buildings are actually built to withstand a 747 flying into it.Parent
Simple Nuclear Chemistry Lesson (Score:5, Informative)
Yes, uranium is naturally radioactive. Much of nature is naturally radioactive, including you, incidentally. There is a certain amount of what is called "background radiation" around you twenty-four hours a day, seven days a week, there would still be even if no human had ever drawn a single breath. Uranium just happens to be quite a bit more radioactive than you are, owing to its nuclear structure.
Now, uranium like most metals doesn't come in handily available lumps in the natural world, but is found in ores: the ore is called pitchblend, in the case of uranium. Humans extract pitchblend (at a ratio of a few pounds of pitchblend to a lot of tons of boring old rock), extract the uranium, and then refine/enrich the uranium so that we get the exact isotopes of it we need for our nuclear power/weapons needs. (Isotopes are the same element, except with a different number of neutrons in the nucleus. Different isotopes of elements have vastly different radioactive properties. For example, the most common isotope of hydrogen isn't radioactive at all, and your body contains a heck of a lot of the stuff. The least common isotope of hydrogen, tritium, has two neutrons in it, and is used for making hydrogen bombs.)
So there are essentially three ways an atom can alter the configuration of its nucleus and release energy. Number one, it splits off into two atoms (fission). Number two, it fuses with another atom (fusion). Number three, it spits out something that was in its nucleus (radioactive decay -- there are a couple of types of this, producing radiation of various levels of danger -- alpha decay, for example, can be stopped with a piece of paper, gamma decay on the other hand will penetrate a meter of concrete). You can cause fission by manipulating radioactive decay in the right way, but it will happen really bloody slowly over time regardless -- uranium, for example, has a half life in the millions of years, which means that of a given sample it will take millions of years for one half of it to radiate and transform into whatever the next step is. Now, a bit of pitchblend just sitting on the counter isn't going to be useful for much of anything, although if you handle it for a few months or years you're at an elevated risk of getting cancer (and if you get radium, a radioactive gas, in your lungs, well, its less than good for you). So you can't, say, just chuck it in a specially designed miniature nuclear power plant and have it power your refrigerator. But a comparitively small amount of the concentrated, refined stuff (a few tens or hundreds of kilograms, as I recall), plus a nuclear plant designed to accelerate the fission faster than it occurs in nature, can literally power a city for years.
Nuclear power, even with the downside of producing harmful radiation (which is almost totally controllable, incidentally), is already very useful. Several countries and many, many communities are dependent on it to keep the lights running, the computers playing WoW, and air conditioners conditioning, the welders welding, and all those electricity-using things modern society depends on. If you're an environmentally concerned sort, you might also be happy to know that it generates extraordinarily little pollution compared to the refinement and combustion of fossil fuels.
This lesson in nuclear chemistry has been brought to you by the letter U and the number 235.
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Re:Yea, and when it explodes/melts down (Score:5, Informative)
Do you have a source for that figure?
all of the examples you gave above are cleanable to an extent.
You do realise that coal-fired plants release radioactive waste into the atmosphere during normal operation, right?
Sources:
http://www.bbc.co.uk/climate/adaptation/nuclear_p
http://www.ornl.gov/info/ornlreview/rev26-34/text
http://www.epa.gov/radtown/coal-plant.htm [epa.gov]
But feel free to google it for more; they're just the top few results for a search for "coal power station radioactivity".
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You are so right (Score:5, Insightful)
"More than 4,000 coal miners have died in accidents in Ukraine since 1991." Radio Free Europe
Thats Ukraine alone. Worldwide? In China? God knows.
Now for Chernobyl:
"Total eventual deaths due to radiation could reach 4,000, including those of evacuees, a statistical prediction based on estimated doses they received. But, "as about a quarter of people die from spontaneous cancer not caused by Chernobyl radiation, the radiation-induced increase of only about 3 per cent will be difficult to observe". Times of London
Since Chernobyl was by far the worst that death count is close to the number of people killed ever in Nuclear accidents (There were some secret problems in the USSR but no one knows.). Throw in the cancers caused by radiation from soft coal combustion and nukes win hands down as a safe alternative. Okay, the pollution is dirty but it is point source and manageable, whereas CO2 is dispersed and systemic and no one knows how dangerous.
Very frustrating to see how fear of nuclear weapons (a legitimate concern) spilled over into irrational fear of nuclear power.
Nevertheless economic and political forces conspire to prevent the nuclear industry from making a comeback. I think a major political PR initiative is need. Homer Simpson your country calls.
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Re:Please... (Score:5, Informative)
The hydrogen and sulfur components are likely released as part of volcanic activity. which is not sunlight driven, although it is driven through the energy released due to the effect of solar gravity on the Earth's core.
I'm not really sure what point you're trying to drive here. Likely the bacteria's ancestors required sunlight to survive, if you are so interested in associating sunlight with everything.
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Actually, that's not entirely correct (Score:5, Interesting)
Actually, that's not entirely correct. No star we know produces elements heavier than iron and nickel, which aren't very radioactive. In fact, they're the most stable nuclei we know.
The thing is, anything lower than iron and nickel tends to release energy when fused into something heavier. Anything heavier than that needs to absorb energy to fuse into something even heavier, and conversely releases some energy when split.
So eventually the reaction stops at iron and nickel. Given intense photon bombardment in the star, most nickel actually disintegrates right back into smaller nuclei, not fuse further into heavier stuff. Iron pretty doesn't do anything whatsoever, and just stays iron.
The thing there is that as you move upwards, the energy and temperature requirements tend to be insane. For example for the next step up from fusing hydrogen into helium, it takes a red giant and temperatures of about 100 _million_ Kelvin to even fuse helium into carbon before blowing itself up.
And most stars either (A) stop short of even that and become a red dwarf, or (B) blow themselves up within seconds when they start fusing helium, because that's a very unstable reaction, whose rate increases with temperature, and temperature increases with fusion rate.
But at any rate, even if you had a star massive enough, you wouldn't get many nuclei past iron, or you wouldn't get them out of the star. By the moment a star got massive and hot enough to start fusing iron into something heavier, it would just rapidly lose heat in that reaction. It just can't explode that way, so at most you'd get a black hole in the end of it all.
So since you mention stars exploding... well, that's actually where the heavier elements come from. Supernovae don't just spread those heavier metals, they _create_ them. The iron, carbon, helium and whatever else was created will be smashed with tremendous amounts of energy and at insane temperatures, and a lot of it will fuse into heavier stuff. And since the star is already blowing up, they'll get spread all over the place.
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Re:Please... (Score:5, Informative)
Yes. Every element heavier than helium was created primarily either in the core of a star (up to iron), during a nova (almost everything else) or as a decay product of the radioactive decay of a heavier element (which was created during a nova or similar event).
The big bang created hydrogen and a little helium; we have stars to thank for everything else.
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Re:This is strange? (Score:5, Funny)
And don't try to tell me it goes off when you close the door, cause I open it real fast sometimes and it is definately always on.
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Re:I'm not convinced by extraterrestrial argument (Score:5, Insightful)
What's important is that this example shows that we also do not really know what is necessary to sustain life. Some things are obvious - the right kind of solvent, water being almost irreplaceable, some source of energy, etc. However, our understanding of the details is still insufficient. In this case we see that radiation, which is viewed as detrimental to life, even though life can adapt to tolerate it, can actually have an opposite role. Can life emerge with only radiation as an energy source? We don't really know, we can doubt it but we can't exlude it as a possibility. Once it's there, can it survive? Now we know, yes.
This opens new possibilities. For example, we have to be more careful when saying that some kind of object in space cannot support life. With what we learned from this, life could even exist on/in interstellar debris, comets etc., where there is definitely not enough sunlight, as long as there are some radioactive elements there - not too little, not too much, but how can we tell where to draw the line? I'm not saying that life exists in such places, only that now we have to accept such a possibility.
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Re:I'm not convinced by extraterrestrial argument (Score:5, Funny)
Yeah, and I think Shakira would have a great time spending a weekend naked with me, but I kind of suspect it might not be true....
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Re:Nuclear Waste (Score:5, Informative)
Of course they cannot. Bacteria (and life in general) work only in the domain of electromagnetic and gravitational forces. They cannot influence the rate of decay of any nucleus in any way.
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