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Comments: 148 +- Science: NASA Discovers Life's Building Block In Comet on Tuesday August 18, @09:04AM
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xp65 writes "NASA scientists have discovered glycine, a fundamental building block of life, in samples of comet Wild 2 returned by NASA's Stardust spacecraft. 'Glycine is an amino acid used by living organisms to make proteins, and this is the first time an amino acid has been found in a comet,' said Jamie Elsila of NASA's Goddard Space Flight Center in Greenbelt, Md. 'Our discovery supports the theory that some of life's ingredients formed in space and were delivered to Earth long ago by meteorite and comet impacts.'"
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How sure? (Score:2, Funny)
Are we sure it is not an alien spaceship ?
Re:How sure? (Score:5, Insightful)
No, all it means is that some of the chemicals needed for Earthly life are also found in elsewhere in the Solar System. Given that the entire Solar System formed out of the same molecular cloud that is not very surprising.
Parent
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This comet orbits the Sun every 6.39 years.
The chemicals on it might just as well have been knocked off from Earth to begin with as coming from elsewhere in the Solar System.
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It is hard to imagine a situation where enough organic or pre-organic material is knocked of the Earth that it would leave that much material on a single comet. Still, there probably some exchange back into space when Earth is hit by a large meteoroid.
hypotheses (Score:5, Interesting)
1) it was scooped from earth or another planet with life by the comet: dubious
2) a planet with life somewhere got crushed and the ejected material that formed the comet got some amino acids in it. weakly possible.
3) Given it's been shown that freezing primordial materials found in space actually promotes the formation of nucleic acids, it might not be much of a reach to suppose that there are natural processes in cold space that will form amino acids.
4) there are life forms that live on comets. presumably then panspermia is ubiquitous.
5) the gel got contaminated on earth. or the mass spec is not definitive about the molecule in question.
I lean towards 5, and then 3 as a close second. Of course 4 would be interesting, as it's direct panspermia. But if indeed the building blocks of life as we know it pervade the universe and occur naturally it also suggests there probably are a lot of similar nucloetide/peptide base life forms out there.
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Re: (Score:3, Interesting)
Reproduction would proceed very slowly in interstellar clouds, due to the low density of the gas.
You'd need a planet for the chemistry to proceed at a rapid pace (due to both temperature and density). I'm not saying that the planet has to be Earth, but a planet would be the most likely starting point.
Re: (Score:3, Interesting)
The competitive, and somewhat older, hypotheses were that glycine and other amino acids were formed in primordial tidal pools, or in the atmosphere during lighning storms, and so on. So this finding is significant in demonstrating that at least some amino acids can be formed under extraterrestrial conditions. This weakens the "Earth is a very special place" arguments. So this is a fairly important finding.
Also kudos to the analyst teams for finding ways to handle such small specimens. This result is the p
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_
A question for anyone who has studied the subject: do we have any idea why there is a difference between terrestrial and extraterrestrial carbon isotope ratios?
To answer your question from what I understand:
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stardust, maybe, or alternatively.... (Score:2)
No no no....we are stardust
Alternatively, as (IIRC) Bill Bryson says in "A short history of everything", we could just consider ourselves to be nuclear waste.
Glycine Deficiency (Score:3, Funny)
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That was lysine. Muppet.
HAL.
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I thought a comet like that was what gave life to earth in the very first place.. maybe this one is coming to replace humans with a more evolved species, this would be convenient.
Panspermia? (Score:3, Insightful)
Or "space spooge" as the kids call it these days. So where'd that life come from?
Tin Foil Hat (Score:3, Interesting)
It also supports the theory that some other planet full of life went *KA-BOOOM*
Aliens of said planet are now patrolling the galaxy looking for the next M class planet to colonize.
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Mission accomplished! [wikipedia.org]
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No, only that there's a high chance of life very similar to us existing on other earth-like planets. At least, similar in the sense that they are made of carbon-based proteins. They might not be intelligent, but at least they'll be edible.
On the other hand, we might just end up being some research team's biosociology experiment.
Re:Tin Foil Hat (Score:5, Informative)
Actually, you're wrong there. As one example, life on earth is composed of right-handed sugars and and left-handed amino acids, but as far as we can tell there's no particular reason why that configuration had to happen - it was a random configuration which manifested early in the development of terrestrial life and spread to all existing species. This means we can only process food with that particular molecular makeup. Early artificial sweeteners took advantage of this fact - their manufacturers figured out how to make left-handed sugars which we could taste, but couldn't digest. In other words you can eat it and it won't cause you any harm, but you won't get any energy from it. What this means is that there would be, at best, only a 25% chance of us being able to use your hypothetical life-forms as a food source, and that's without having to worry about whether they provide us with the right vitamins/nutrients, what sorts of hormones and toxins might be in them, etc.
Parent
Re:Tin Foil Hat (Score:4, Interesting)
If we can eat, and be nourished by, alien life then any bacterium from the same environment could use US as food as well.
And even then alien predators would likely still TRY to eat us if they thought we might taste good, or could be used as incubators for their parasitic, chest busting, off-spring, or they might just want to hunt us for sport with plasma based weapons while using active-camo.
Parent
Re:Tin Foil Hat (Score:4, Funny)
So what you're saying is that we only have a 25% chance of being able to digest the alien species, but a 75% chance of being able to use them as a calorie-free artificial sweetener?
Queue the countdown to NutraSweet funding the SETI program in 3...2...1..
Parent
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Aliens of said planet are now patrolling the galaxy looking for the next M class planet to colonize.
I first read this as "colorize", and I think I like it better that way. Somewhere out there is a super-advanced race that couldn't care less about biospheres and intelligent races and such, but just really likes blues and greens a lot better than browns and reds.
Call them the Turnerites.
Delivery (Score:2)
The universe has delivery now? If only it'd get an internet presence I bet it'd really take off.
Again? (Score:3, Funny)
Don't they make a claim like this every other week? It isn't getting any more interesting. Elements of life found in an old pile of pancakes left behind in an abandoned nuclear power plant, now that would be interesting.
Re:Again? (Score:5, Funny)
Ha!
q: Whats the difference between average slashdotter and average comet?
a: one gets to spread its "life's building blocks" around
Parent
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Re:Again? (Score:5, Funny)
Parent
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Yeah, and each time, it's obvious the evidence was planted.
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Yeah, and each time, it's obvious the evidence was planted.
I RTFA and tried to figure out how they are 100% certain the glycine is from space. Apparently it's because of the isotope ratios of C12 and C13, with more C13 being present in space. My question is, how much glycine did they collect? The link to the analytics on NASA's website keeps timing out.
Anticlimactic (Score:2, Funny)
So now we know
Obviously, the discovery of sentient life "abroad" is going to be anticlimactic now.
Way to ruin it.
Glycine isn't that complex (Score:2, Insightful)
http://en.wikipedia.org/wiki/Glycine formula is NH2-CH2-CO-OH
It's not that complicated. Shouldn't we be waiting to get excited about something more complex?
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It's not that complicated. Shouldn't we be waiting to get excited about something more complex?
Yeah, I'm waiting for: 'Scientist find building blocks for taco's in comet, decide to build lunch.'
Panspermia (Score:2, Informative)
We may have sent men into space (Score:3, Funny)
What's all this I must wait & try again stuff about did someone
Reminds me of Spore... (Score:2)
Didn't you start life on a planet in Spore with a comet?
Maybe we are all part of a gigantic video game like spore?
Maybe the "gamer" is a gigantic A.I. person?
Maybe The Matrix is real??
Sci-fi (Score:2)
It's quite amusing to think of all the games and sci-fi plots that have been based around alien life forms landing on a planet and taking it over in the context of this theory, because, well, if true, then we're those alien life forms, the only thing we're missing from most plots is a hive mind!
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he said "Hive Mind".
What they did not tell you. (Score:5, Funny)
Glycine is simple... (Score:5, Informative)
so Spore is correct ! One for the corporates! Yaay (Score:2)
Great!
So Spore was actually right.
Now i can let my son play spore and help him learn that life came from comets and that we ought to smash each others heads to become civilized.
Aren't these people supposed to be scientists??? (Score:2, Funny)
Apparently they can't be bothered to pick up a textbook and learn that Redi and Pasteur proved it doesn't work like that a couple hundred years ago.
It's call the law of biogenesis.
Stop spending tax dollars trying to prove your Theory when there is already a scientific law disproving it.
If you want to spend your own money on it fine, just stop spending mine on your junk 'science.'
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It's call the law of biogenesis.
Stop spending tax dollars trying to prove your Theory when there is already a scientific law disproving it.
Because, you know, a scientific "law" is the absolute truth........
Wikipedia happens to say that the law of biogenesis is "that modern organisms do not spontaneously arise in nature from non-life." Really, what makes y
dinosaur comics covered this DAYS ago (Score:2, Informative)
Faulty Logic? (Score:5, Interesting)
"Our discovery supports the theory that some of life's ingredients formed in space and were delivered to Earth long ago by meteorite and comet impacts."
Instead it only supports what Dr. Pilcher says in the article:
"The discovery of glycine in a comet supports the idea that the fundamental building blocks of life are prevalent in space, and strengthens the argument that life in the universe may be common rather than rare."
In other words, it's just saying that amino acids are not that rare. If they're not that rare, why can't Earth have made them on it's own?
After all the Miller/Urey experiment [duke.edu] in 1953 showed that amino acids can be produced fairly easily if a few simple conditions are met.
Miller took molecules which were believed to represent the major components of the early Earth's atmosphere and put them into a closed system
The gases they used were methane (CH4), ammonia (NH3), hydrogen (H2), and water (H2O). Next, he ran a continuous electric current through the system, to simulate lightning storms believed to be common on the early earth. Analysis of the experiment was done by chromotography. At the end of one week, Miller observed that as much as 10-15% of the carbon was now in the form of organic compounds. Two percent of the carbon had formed some of the amino acids which are used to make proteins.
Maybe comets and meteors with amino acids were hitting earth as well. But finding them all over space also strengthens the idea that they're not uncommon to produce, and therefore also strengthens the theory that Earth could have produced them by itself. Either way seems like a guess to me.
Fun fact for the day: The Murchison meteorite [wikipedia.org] which fell in Australia in 1969 also contained common amino acids such as glycine, alanine and glutamic acid as well as unusual ones like isovaline and pseudoleucine.
Comets... (Score:2)
No direct proof (Score:3, Informative)
'Our discovery supports the theory that some of life's ingredients formed in space and were delivered to Earth long ago by meteorite and comet impacts.'"
Again guys, you are filling in gaps with information that fits your ideal world and to support other theories but there is no direct evidence that events happened this way. There is no direct evidence that glycine can survive the impact or that it actually was transferred from space-borne objects. Example: A 30 year old brown-haired person lives in San Francisco and another one who is 50 years old lives in New York. Does that mean the one in San Francisco is the offspring (and therefore related) of the one in New York either because the person in New York traveled to San Francisco then had a child or had a child then the child moved to and grew up in San Francisco? Yeah it can mean that but without asking the people involved or seeing it happen first-hand you can't just fill in the blanks and assume you are correct. We obviously can't ask glycine where it came from so we have to see it first-hand be transferred from a comet/meteorite to Earth and remain intact and viable before we can really say for sure that supports the theory that life's ingredients came from out of this world. Something generic like 2 samples of glycine or 2 brown-haired people are too generic to conclude they are related, but feel free to make that gross assumption anyway to fit theories of evolution.
Stuff != life (Score:5, Interesting)
Um... it didn't. "Building blocks for life" does not equal "life". But once the 'building blocks' formed, life could get started... almost certainly on Earth. See, e.g., here [discovermagazine.com].
Parent
Re:Where did that stuff come from? (Score:4, Interesting)
"What caused the life to form way out there?"
As far as we can tell life didn't form way out there. Just an amino acid fundamental to life. Life as we know it requires liquid water, a certain atmosphere, gravity, and a bunch of other requirements.
"It's fine and dandy to push the building blocks of life off-planet, but how can those blocks then be explained?"
The building blocks for life have to come from somewhere, they don't just appear out of nowhere (or do they?). After all, isn't life really just the combination of left over heavier elements created through exploded stars and other space junk that just happened to end up on earth through meteorites, comets, and the accretion process...
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Now, I know that this amino acid in RTFA is not life. I am not really surprised that it is found - space observations have shown a lar
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