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Strange Bacteria Sustains Itself Without Sunlight
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."
Is uranium naturally radioactive or is this human produced nuclear waste? For now, I'll assume the former.
In case it is about 'normal' uranium, would it be viable to use its radioactvity as a power source without the creepy fission reactions? Would it then also be possible to turn human nuclear waste into a useful energy source? Or is the amount of energy released by radioactivity too small to turn into useful work?
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I love these kinds of stories. We can blow this planet up, it can ice up to the equator or even shift on its axis and life will survive and take another shot in a few thousand millennia.
On a practical note I wonder what a handful of this particular type would make of a nuclear waste pile...
Comments along the lines of "we've found life in such & such extreme enviroment which makes life elsewhere in the universe more likely." Hmm , I'm not convinced. Thing is , I think life evolved in a fairly benevolent enviroment (and even then it took quite a few billion years) where organic molecules had time to arrange themselves into precursors living cells. I very much doubt this would have happened in somewhere blasted with radiation/intense heat/cold/whatever where extremophiles live. However once the mechanisms of life are up and running THEN things can adapt to extreme enviroments because they have a number of pre existing mechanisms that be mutated to do allow this , but that doesn't mean that these mechanisms could have evolved in the extreme enviroment in the first place. Its a bit like an Alien arriving on earth and seeing humans standing on top of Everest and then assuming that a large ape evolved 7 miles up in freezing cold and low oxygen conditions. Adaptation to an enviroment is NOT the same as emergence within it.
I think that more research should go into seeing if the bacteria could break down nuclear waste. And if it can't, at least drop a bucket full on North Korea!
Even chernobyl has had scant effect on its surrounding enviroments
Except for the 2000 people who developed thyroid cancer. But hey, the opposite end of the scale from hippies are the corporatists, who figure it's fine to kill a few people with lingering, painful and expensive deaths, as long as their share price goes up a buck or two from it. And if their stock doesn't, they'll invest in hospitals to hedge their bets.
It's the price of "progress", as long as they don't have to pay it.
The independence of Ukraine and the economical crisis in the former Eastern Soviet Union were also influenced by Ukraine.
Does that mean, that on Earth the "big elements" are actually from big OLD stars from Long Long ago..almost at the time of big Bang??
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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.
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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I'm still unhappy about the waste created: "Most of the radioactive isotopes in high level waste emit large amounts of radiation and have extremely long half-lives (some longer than 100,000 years) creating long time periods before the waste will settle to safe levels of radioactivity."
<sarcasm> Future generations will probably be sincerely delighted about how responsibly we are handling radioactivity today, if they manage to notice before it is too late.</sarcasm>
And to further answer the GP's question, there's been plenty of time since the Big Bang for this process to happen (several times). Large stars burn through their fuel much faster than well-behaved dwarf stars like our sun. I believe that a supergiant star can complete its lifecycle in about 15 million years. That means that if current estimates on the age of the universe are correct, that it could have happened over 900 times by now, assuming a perfect linear succession of supergiant stars. The real estimate is probably much closer to a couple hundred, but there has certainly plenty of time for all the heavy elements in our planet (and the rest of the solar system) to have formed in the hearts of stars since the Big Bang.
As Carl Sagan said, "We are all made of starstuff.".
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Hydrogen - air will burn over a very wide range of ratios - 4% H to I think 74% H in air. The result is that it would be very unlikely that the hydrogen could disperse rapidy enough to not be involved in the fire.
that a life form that uses radioactivity is fairly stable.
news on chernobyl shows that life can adapt to radioactivity quicker and better than we thought too.
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The Big Bang also created lithium. In fact, many question whether stellar fusion can create lithium at all.
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