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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."
Yes, these are natural uranium ores in South Africa.
The radioactive half-life of uranium 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) use radioisotopes with half-lives of tens to hundreds of years.
(a) It's naturally radioactive. Also, from TFA: "Coauthors of the present paper learned of a new water-filled fracture inside a South African gold mine near the Johannesburg metropolitan area and viewed it as an opportunity to study subsurface rock uncontaminated by human activities."
(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."
Yes.
WTF. It naturally does creepy fission reactions slowly. Put lots of it together under the right conditions and it naturally does creepy fission reactions quick enough to be useful.
radioactive materials absolutely do not rely on sunlight. They rely on big huge stars to make big fat elements, then explode spreading them all over the universe where the coalesce into planets like the Earth.
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.
“Common sense is not so common.” — Voltaire
Russian satellites often use decay reactors to drive the electronics. You don't get a whole lot of energy out of it, but the reactor can be quite small (small enough to put in a satellite) and lasts for quite some time. (20-100 years)
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?
“Common sense is not so common.” — Voltaire
(Slashdotters who already know this can feel free to ignore it. Everyone has to learn science sometime, if you had the good fortune to learn it years ago no reason to jump on someone who hasn't yet.)
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.
Help poke pirates in the eyepatch, arr.
"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?
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.
Victims of 9/11: <3000. Traffic in the US: >30,000/y
They live off one of the products of nuclear decay.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
(and even then it took quite a few billion years) .5 to 1 billion years after the formation of the Earth; 3.4 - 3.9 billion years ago.
Not really. Current estimates place the beginning of life at
Take a read of the Wikipedia article on the history of our planet, it's a fascinating story.
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??
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.
It's official. Most of you are morons.
You apparently do not know the difference between a nuclear detonation and a nuclear meltdown.
What you describe is a nuclear detonation, whis is physically impossible to be produced by a nuclear power plant.
A meltdown is a different beast, where it is not the meltdown itsself that causes the damage, but the resulting mechanical failures from the sudden release of heat. Incidentally, at least in US designed reactors, this has been taken into account and is why we have containment domes over the reactors. This is why Three Mile Island was a non-event and Chernobyl was a big one, had Chernobyl had a dome, it would have released considerably less radiation.
You say you want a revolution....
capable of instantly eradicating all life within an 10 km radius,
o wer.shtml/ colmain.html
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
But feel free to google it for more; they're just the top few results for a search for "coal power station radioactivity".
It's official. Most of you are morons.
Chernobyl was a big one
t m
yep, and to add to your point, chernobyl did not kill everything within a 10km radius, nor is it "uncleanable" - in fact nature has done so well at cleaning it up / living with it since (most of) the humans left, that people are talking about making it a nature reserve: http://news.bbc.co.uk/1/hi/world/europe/4923342.s
There's a lot more action going on at trek conventions (including some really extreme stuff at the big cons) than most folks realize.
Biggest problem I see with the guys is that they look like 3's but ignore any female less than a 7.
Either fix yourselves up a bit or make your standards a bit more realistic.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
Coal burning also releases more radioactivity into the atmosphere than all the nuclear accidents combined.
Its worth making clear as well that the Chernobyl design was a 50 year old one that was known to be risky. Modern designs are not.
But the earliest living things on earth might have been bacteria like the ones near hydrothermal vents. They're in a kingdom called Archaea and are small and simple in design.
Their chemical traces have even been found in sediments from the Isua district of west Greenland, the oldest known sediments on Earth at about 3.8 billion years old. This means that the Archaea (and life in general) appeared on Earth within one billion years of the planet's formation, and at a time when conditions were still quite inhospitable for life as we usually think of it.
[quote continues]
The atmosphere of the young Earth was rich in ammonia and methane, and was probably very hot. Such conditions, while toxic to plants and animals, can be quite cozy for archaeans. Rather than being oddball organisms evolved to survive in unusual conditions, the Archaea may represent remnants of once-thriving communities that dominated the world when it was young.
Off topic, but heck, I get a lot of interesting info from off topic posts...
Hydrogen, helium and a tiny bit of lithium existed after the big bang. *Everything* heaver was created in the core of stars, or as a decay product of something produced in a star core. The reference to iron is a relevant, but not as the poster intended. Fusion of light elements generates more energy than it takes in and produces a heavier element. That is, until that heavier element is iron. Producing iron or anything heavier by fusion requires more energy than is released.
However, these heavier elements are still produced in star cores before nova because there's so much energy around for these reactions to happen. Not a lot of the heavy stuff in comparison to other elements, but still enough. And novas/supernovas distribute it in a continuous process that has been happening since the first giant star went supernova some time in the 1st 1/2 billion years of the universe. We are all nuclear waste, or as Carl Sagan said more poetically, "star stuff contemplating the stars."
Wow, this is really amazing, because all the bacteria in our digestive track surely relies on sunlight for life.
Bacteria, in general, do not use photosynthesis. A few do, but very few. What bacteria use for an energy source varies quite a bit, actually. But it's certainly not strange for a bacteria to not need sunlight, since the vast majority don't.
Technically, these aren't event bacteria. They're extremophiles which means they fall in the Archae domain, not the Bacteria domain. But maybe I'm being too picky.
...all I can think about was this awful novel by Robert L. Forward called Camelot 30K. Good science, bad writing.
I might as well throw down on this a bit...
1: CLEAN TEETH - Buy soft dental picks- easier than flossing and smaller than a toothbrush. They sell them in packs of 50. (This becomes a huge issue in your 40's when the rest of the guys start losing their teeth.)
2: CLEAN BODY (relative to your country's standards). She shouldn't be distracted by the blackheads on your nose.
3: SMILE - and say her name. The most important word in any language is a person's name. It gets their attention in a crowded room almost instantly.
4: Avoid "one itis" / "your my soul mate". I.e. KID them a bit. If no interest- move on to find someone who is.
5: Flirt with every female regardless of age or appearence. Boosting other's egos and giving them a reason to smile is a worthwhile thing for a human to do for others. It helps you because you get over only flirting for sex and "true love."
Also: Ignore every romantic lie you see in movies. If you act the way most romantic movies show you to in real life you are going to creep her out/be "too heavy" or would even be stalking/setting yourself up for an injunction. Despair.com says it best. "Persistance: It's Over Dude. Let Her Go."
The truth is knights in shining armor were pretty vulgar lusty dudes. Women are not attacted to wimpy guys.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
You're mostly correct, but a few things. Read the book "Stellar Interiors" by Hansen & Kawaler; it's a standard graduate text on the lifecycles of stars. I actually took a few classes on the topic from the Kawaler of that trio.
For one, it's a white dwarf, not a red dwarf. Red dwarf stars are just very small stars actively burning hydrogen. Two, stars don't "blow themselves up" the instant they start fusing helium to something heavier. The red giant phase is when some stars do go through a period of instability which can result in novas (not supernovas), which is essentially the star sloughing off a small part of it's outer layers.
The way this all happens in reality is there are 3 possibilities: 1. the star is so small it never starts burning helium, and becomes a white dwarf, 2. the star does burn helium, but can't burn C and O, and stops as a white dwarf, 3. the star has sufficient mass to start fusing C and O and things get interesting. The class of stars that can begin to fuse C and O are essentially now on a runaway train, because each reaction proceeds progressively faster in the core of the star up until iron begins to be created.
Yes, as soon as a star begins to fuse iron in its core, energy is actually removed from the core of the star, causing it to lose all of the thermal energy that had supported it against the force of gravity. So in some sense the creation of heavier elements is what actually causes the star to explode.
Within a very very short period of time the core of the star is in gravitational free-fall and collapses in on itself, releasing a tremendous amount of gravitational energy in the process. The core collapses and rebounds, sending shockwaves through the entire star and it "blows up" as a supernova, producing a tremendous amount of neutrinos and gamma radiation. You are correct in saying these elements don't get out of the star, they go into forming the either a neutron star or a black hole that's left of the core. The creation of heavier elements is from the gigantic shockwave propagating out of the star.
Hmmm.
Stable passionate relationships with three ladies for 7, 9, and 18 years. Was up to five but one moved away and the other one finally found mr. right (which is cool for her). Started a new one recently that looks promising.
Everyone's happy and knows up front that I'm a bachelor and I have relationships with multiple women.
Close enough I guess.
Oh yea... I forgot #6
#6: FOR GOD'S SAKE LEARN TO DANCE. Swing- Country Western-Whip, Ballroom, Foxtrot. Just do it.
a) You'll have lots of different females in your arms.
b) A LOT of marriages and long term relationships come out of dance classes.
c) Programmers are *EXCELLENT* at the more complicated dances (like "Push"/"Southwest Whip").
If you can dance well, when you are old you can get free cruises and spend them dancing and romancing (tho officially you are not allowed to romance, that's with a wink and a nod, know what I mean... say no more...)
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
It is quite possible to be sufficiently knowledgeable about either biology or physics to state that no bacteria can "catalyze" a nuclear reaction. This isn't cutting edge physics or complex biology; fission reactions aren't catalyzed by chemical ones. At all. That doesn't leave enough wiggle room for you to be right.
I could maybe, possibly, see bacteria concentrating fissile material. That would speed up the rate of fission, increasing both decay and radioactivity. Wouldn't work with all forms of radioactive decay though - not everything radioactive is fissile. And you'd be trading 1X years of 1Y radiation for 1/2X years of 2Y radiation; you'd just turn long lived low hazard waste into short lived high hazard waste.
But catalyze a nuclear reaction with a chemical one? Not a chance in hell. You can't change a compound's nuclear properties by chemical proccesses. Unless you want to give medival alchemy a shot, you are SOL.
Erotic is when you use a feather. Exotic is when you use the whole chicken.