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Murchison Meteorite Still Contentious
An anonymous reader writes "The well-known 1969 meteorite that fell 60 miles north of Melbourne, Australia, remains remarkably contentious today. The 100 kilogram carbon rock : a) contains pre-biotic proteins and 12% water; b) harbors 50 amino acids not found on Earth; c) favors the tell-tale signature of biochemistry based on a dominant left-handed chirality, compared to random or racemic mixtures found in test-tube syntheses. While terrestrial contamination (even interior to the meteor) may discount this so-called 'Murchison meteor', its light isotopes of carbon and nitrogen suggest the left-handed amino acids not found elsewhere on Earth have the same ratios as the right-handed ones. This would not be the case if, say, bacteria was just making the left-handed ones after impact. Seems quite a controversy from down-under."
You'd think that after they found what appears to be microscopic life (fossilized, rather) on Mars, it wouldn't be that big of a stretch.
However, it is fairly interesting that that many amino acids are left-handed. Organic molecules tend to form in pretty much the same way in any given environment, so I'd think that if those aminos ARE from Earth, they'd be from someplace strange, like a hydrothermal vent. How they would've gotten onto a meteor from there, who knows.
Guess the DNA spiral the other way just like the water in the toilet down under. ;)
So does this prove that God was left handed?
Steven V>
I patented screwing your mom. But it got revoked for "prior art."
Mmmm. Big words. Me no understand.
And chunks of it are now on sale at Ned Flander's Leftorium.
Fan-diddly-tastic!
Left handed terrorist amino acids trying to subvert the way of the right !
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
nice, and I was third...
We really are all aliens!
------- "From bored to fanboy in 3.8 asian girls" ----------
there goes the human race! ;p
moo
I m just a simple caveman, your fire scares me. These pre-biotic proteins you speak of are unfamiliar to me!
So if the big debate is whether these "rocks" from space contain the building blocks of life, but are being contaminated when they hit earth. Why don't we send up a robot (Or what have you) into space and collect some rocks that have not been on earth?
To me, if you collected about 20 or 30 of these things, it would answer the question rather quickly. Yes, I know that does mean we would get rocks with ammo acids, but sitting waiting for the rocks to come to us seems to be a waste of time.
Linux O Muerte!
wow, this is really interesting... I've never heard of this meteor before, however I find this really cool.
I wonder why this was never mentioned in any of my chemistry, physics, geology, or biology classes in high school or college (last 10 years)?
on a side note... is anyone else creeped out by the picutre of the guy halfway down the page?
*shudder*
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.. is find and orifice and pump the meteorite full of shampoo. If all the 'life' on it dies, then it's extra terrestrial. :D
The point is simply that you cannot infer any biochemical 'facts' about extraterrestrial compounds once they've been exposed to Earth's lifeforms.
Try not. Do or do not, there is no try.
-- Dr. Spock, stardate 2822-3.
How would organic material from earth make it into the center of an object like this? Can the force of the impact explain that some how? Just want to know : )
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On thing seems abundantly clear: There's no life left on the world it came from. I hope ours doesn't pose a base for such a heated debate on some other world species some day.
A feeling of having made the same mistake before: Deja Foobar
Perhaps even more interesting (especially if you're already familiar with the debate) is the fact that highlighting a word or phrase on that page causes a browser window to pop up with the results of a Google search on that word or phrase...
Not technically very difficult, but a cool idea...
...Earth. They could be of terrestrial origian and thrown up a billion years ago or so by volcanic activity or a large meteor collision with earth, eventually arriving on earth again after a billion years of orbiting near the Earth. They could be leftovers from a very early time when left handed and right handed life coexisted on Earth.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
.....compared to random or racemic mixtures found in test tubes on Earth. We have yet had no other "lab" from which to study life and it's building blocks (life as we know it: carbon based and mostly made of water). Therefore, the sudden appearence of such components from the stars might very well appear to be "based on dominant left-handed chirality" when compared to the billions-old formula we have here on our planet.
We also don't know how the environment of space will effect amino acids contained in the rock. Since these amino acids (and other material) are foreign, then how do we know that it isn't natural for them to be collected in such a manner?
Never forget the scientific method. You have to ask questions. After you're done asking questions, submit to your peers for them to ask questions.
It really isn't compelling at all. It's similar to how UFOlogists focus on half truths and anamolies that confirm their theories, while ignoring the evidence that shows how 90-95% of all sightings are reasonably explained (the tons of disconfirming evidence). They also turn their nose up to the community and the world, effectively becoming the closed-minded character that they try to call the real scientists: Real scientists submit their work to thousands of peers and accept feedback and analysis. Psuedoscientists do not, and yet they call the critical thinkers that reject their ideas closed-minded.
OK, rant over.
Soviet Russia, that's where!
I think the major importance of this is that the theory of evolution(which God could direct!) does not account for the switching of one set of amino acids to another. That means that these acids are not from Earth, or at the very least not from the epoch.
You can't judge a book by the way it wears its hair.
From the article: A curious aspect of Earth's life forms is that they contain (with few exceptions) only left-handed amino acids. In contrast, when scientists synthesize amino acids from nonchiral precursors, the result is always a "racemic" mixture - equal numbers of right- and left-handed forms. Scientists have been unable to perform any experiment that, when starting with conditions believed to emulate those of early Earth, results in a near-total dominance of left-handed amino acids, says George Cody, a geochemist at the Carnegie Institute of Washington.
In many cases, the levorotary forms are lower energy structures and would be favored during synthesis. The fact that many L based systems are almost exclusively so is dependant upon the larger structures that are based upon amino acids and other small molecules. Often a D form of a molecule will not be able to integrate into a L structure.
This is not to say that D forms cannot have biological activity however as there are many instances I can think of where racemic mixtures of molecules can have biological activity. For instance, the 2 chiral forms of carvone have completely different smells due to receptors in the olfactory epithelium being activated by each of the racemic forms.
Some instances of similarity of molecular structure but different chirality have also resulted in catastophies. One only has to think of MPTP poisoning the neurons of the substantia nigra or potentially thalidomide.
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here's a couple of reasons I can think off the top of my head:
1) we've got to get the ship someplace where there are "space rocks". a low-earth orbit really isn't going to accomplish that - you'd have to go to the asteroid belt for a ready supply. that's not easy. or, conversly, you land someplace where rocks may have accumulated (ie, the moon, mars).
2) if you send a ship to a place with lots of space rocks, the ship is going to get hit by a lot of space rocks. shielding becomes a problem.
3) if you land some place, you're stuck getting rocks next to where you land (like viking) or you've got to build a way to move around (like pathfinder)
4) building a reliable, completely automated assay for amino acids is not trivial. if it's mobile, that's going to be even less trivial.
This will remain controversial for scientists until one of two things happen.
1. There are other samples from the places that they claim the meteorite is from to compare to that are of the appropriate age.
or...
2. The current crop of scientists have passed on. There is a joke about the physics community that theory doesn't really advance until the last generation has died off...;)
I hope it's the former rather than the latter. That implies a more than a few expeditions or at least sample returns to the source of origin...which we all know what that is! ;)
Do you know why the road less traveled by is littered with the bones of the unwary?
"How many times will science have a victory over the church before we can finally kill God for good?"
What victory over the church? Science is good for proving that things exist, but it's not very useful for proving that things don't exist. If you're drawing the conclusion that God doesn't exist by what is or isn't on a meteorite, then you're not using science.
contentious ( P ) Pronunciation Key (kn-tnshs)
adj.
Given to contention; quarrelsome. See Synonyms at argumentative. See Synonyms at belligerent.
Involving or likely to cause contention; controversial: "a central and contentious element of the book" (Tim W. Ferguson).
Yeah, ok.
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turn the other way round down there? I mean I dont know much about the left right things, but since the water turns the other way around and just thinking about the average aussie I wouldn't count this as something special, everything down there is the other way around wouldnt supprise me if they had some extra aminoacids to go around :) (yeah yeah I know were based on 21 or so here on earth and that could mean all sorts of different stuff - but who cares I just got my result from winterexams and they were good :))
pr0n pr0n pr0n
Now this is interesting, because no life on Earth uses left-handed Animo Acids. They all use Right-handed ones. Both left and right occur 50/50 in nature, so any ratio of left handed Amino Acids that outweighs right is...
Well...
Something would have had to *make* the left handed acids...
And mine was 4th, not 3rd. :(
We are teh collective sukc.
If bathwater can twirl the other way in the southern hemispere, then maybe amino acids can be left-handed.
Oh ...and maybe the scientists in Oz just never noticed.
Oh and one more thing ...this post is not informative.
How many times will science have a victory over the church before we can finally kill God for good?
'Could it be that the Saint had not heard the news; that God is dead?' - Nietzsche
DARWIN WINS AGAIN!
How exactly?
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We are the space robots.
We are here to collect you.
We are here to collect
the terrible secrets of space.
It seems as though the trend in the history of science has been extending terrestial phenomenae, this has been happened on all the other branches of science except life sciences, thus we should not discount the discovery of perhaps not extra-terrestial life but at least ET organic chemistry.
Who looked at this article and saw ASCII smiley faces? :a) ;b) ;c)
Please, I want to hear how pathetic I really am...
(^o^)
Is this another debate as to which is better? Lefties or Righties?
Good security is based upon reality and common sense. Common sense is a function of having common knowledge.
well the first thing you can forget about - they never went there, hell will be frozen solid before I believe that that string attach thingy was more than 2 m. from earth... (how that mirror that reflects laserbeams to measure the distance to the moon got there?) That doesnt exist either!!! Heck this thread is a figure of you imagination - now quit being a nerd and think of some really hot blond chick!!!
2. Send cowboy neil instead, last I heard he had some funky moves to deal with that.
amino acids not found elsewhere on Earth
Every time I hear this I get rather angry. Are these people really so arrogant as to be absolutely certain that we have already found and identified ALL amino acids, presently on earth? Is there no chance at all, that these same amino acids could be present somewhere (bacteria in deep sea vents, perhaps) and we simply haven't found them yet?
I'm not trying to suggest that, the amino acids found on the meteor are not extra terrestrial. But, I just get angry at these people who seem to feel that they have seen everything that there is to see on terra firma.
Except that toilet water doesn't, of course.
googled
"When it rains, it pours." --Morton's Salt
Easily the most informative troll ever.
Sounds very sinister. :)
.... Leading biochemistry lab.
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GeneralEmergency
Pre-biotic proteins, 12% water, 50 amino acids not found on Earth, biochemistry based on a dominant left-handed chirality
That's the ingredient list on the back of my Aussie Moist 3-Minute miracle conditioner!
Makes you wonder
carbon and nitrogen suggest the left-handed amino acids not found elsewhere on Earth have the same ratios as the right-handed ones.
Maybe Bizzaroman took a shit?
Case closed and make mine a Foster's. G'day.
Sigs are bad for your health.
Have you not heard of sheids and warp drives? You must be from Langley.
Fact: the meteorite contains ammino acids, and chirality that is not generally found in terrestrial organisms.
Fact: This meteroite is HEAVILY polluted with terrestrial organic matter.
Conclusion: While ammino acids are generated in space, they seem to mimic the compositions found when we try to synthesize them in the lab.
Aside: You can produce the same results with some methane gas, water vapor, and ionizing radiation.
Move along, no controvesy here.
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
...that maybe they had their microscope slides upside down and what appears to be left-handed is really right (or wrong in this case)??????????????? Really just a matter of perspective.
I live in Melbourne, was born in '73 and I've never heard of it...
Victory over the church hardly seems relevant to the question of god's existence.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
Something of the scientific world counterpart to the "New Age"ers.
I get the feeling that if one of these metorites were to break open and expel a full-formed 3 headed talking green alien, they'd surmise that it was probably nothing more than a spontaneous mutation of the lab mascott.
OS Software is like love: The best way to make it grow is to give it away.
Although of course this would be an imense venture, probably requiring a permanent base on the moon and who knows where else, but it would remove the dependency of technology on earth from our fragile ecosystem, and let's face it, we've taken a lot of the easy metals out of the ground, and it's only going to get harder and harder to find. Another important point to remember is that although going up is expensive, going down is dirt cheap. ;)
My two cents. Joshua
When in danger or in doubt, run in circles, scream and shout!
You got FPFP. Nice job.
Given that there are three sets of researchers doing work on the same piece of rock and arriving at such different results, it seems that someone is making an assumption about the sample (the meteorite) having a consistent composition.
Is this necessarily the case?
I don't know the answer, but it seems like a reasonable question. Anyone here know about meteor composition and consistency?
well he claims to have a Phd in the life sciences but unthinkingly types shite like this. no-one seems to have pointed out yet that varying isotope ratios are the consequence of living at the bottom of an atmosphere, ie transmutation from c12 to c14 occurs way up there in the sky as a result of high energy radiation. pardon my spelling but I am completely out of it on beer and wine.
One logical conclusion seems to be that the meteorite contained extraterrestrial life, or perhaps a complex network of biochemical reactions that isn't quite life but a precursor. Those may have existed briefly in space and ceased long ago, or it may have been destroyed when the rock fell to earth, or we may simply not recognize it. I mean, if it doesn't have distinct membranes or other structural features, we wouldn't easily recognize life or close precursors of life at all with our current technology.
Only on earth could it be hotly debated...
Um, that's just silly. Until we make contact with intelligent life on other planets, we have no way of knowing whether or not those intelligent life forms on other planets (assuming they exist) would debate the matter.
On thing seems abundantly clear: There's no life left on the world it came from.
There's no evidence that it came from a world. Organic compounds form in interstellar space, and it has been speculated that life (or something eerily like it) could form in space. Or not, but in any case, I think you're trying to read far too much into this.
DARWIN WINS AGAIN!
How exactly?
Sneak goal in the 78th minute.
Disallowed for offside (much to the annoyance of their Beagle mascot).
Recent research suggests that there is an excess of L-amino acids (the specific enantiomer used in life-proteins) found in space, suggesting that the chiral specific process involving circular polarized light (mentioned in the article) could have lead to the amino acids that were found on the Murchison (and other meteorites).
...
From the article:
Recently it has been discovered that an excess of L-amino acids is present in the Murchison and Murray meteorites indicating that a preference for L-amino acids existed in solar system material before there was life on Earth. This supports an idea, first proposed by Rubenstein et al. (1983, Nature 306, 118), for an extraterrestrial origin for homochirality.
In this model the action of circular polarized light on interstellar chiral molecules introduced a left handed excess into molecules in the material from which the solar system formed.
If our own solar system formed in such a region of high circular polarization, it could have led to the excess of L-amino acids which we see in meteorites and to the homochirality of biological molecules. It is possible that without such a process operating it would not be possible for life to start. This may have implications for the frequency of occurrence of life in the universe.
The bees are on the what now?
I think of civilization and technology as a major/minor cycle. Technology doesn't always advance... sometimes it's lost. Sometimes entire advanced civilizations are wiped out and a hunter-gather society emerges in its stead. Now imagine this happening to the whole of civilization. Imagine we DO go to Europa, and leave behind a streptococcus. We then lose spacefaring technology for a period of a million years, then regain the technology to complete the cycle.
The new civilization travels to Europa, and finds... simple creatures with earthlike amino chains! At that point we will have discovered extraterrestrials.
Of course one has to wonder if the earth-europa contamination hasn't already happened millions of years ago by an ancient civilization now forgotten. Or perhaps it was vice versa... spooky.
As long as the starting ingredients for the reaction are non-chiral, or are chiral but racemic, then both the L and R forms are equally favored. The only case where the L is favored is when you're making it from reactants that are also L-form.
cool....
LONG LIVE ROCK!
The most important thing any republican needs to know.
Isn't that a bit like saying Disney isn't relevant to the question of Micky Mouse's existence?
We may laugh at folks in under-developed countries for their silly superstitions, but the sad fact is a good half of the US population has problems distingusing facts from fairy tales.
OTOH, science does provide a mechanism to show that a given explanation is consistent enough with all known data so that we may use that explanation to do useful things within a given domain. Science also provides mechanism to test predication resulting from the explanation against nature. The process generally leads to the simplest explanations, as those tend to be easiest to test and exploit.
In this case, if the organic material in the rock can be adequately explained with terrestrial sources, then we must accept the terrestrial explanation until such a time that we might get more data necessitating the complication of extraterrestrial life. By prematurely assuming extraterrestrial life, one runs the risk of contaminating the process.
Putting all this together, if we limit our 'truth' to a minimal set of useful and testable explanations, such as which we might get with the strict adherence to Occam's razor, god is unnecessary. After all, we turn on a light by completed a path for electrons, not praying. We insure our food supply by cross breeding plant and the application of chemical fertilizer, not by ritualistic acts of sex. We know the earth has an eccentric orbit, so see no need to dance to entice it's return on the winter solstice.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
A search for Kvenvolden turns up a lot of hits on PubMed, but no evidence as far as sequence or structure submissions. It would be interesting to see the evidence that backs up the claims. If the rocks truly did contain bits of ET, I wonder what a BLAST homology search would turn up.
This has to be one of the least coherent posts I've ever read on this site. Congratulations, whoever you are! That must have taken some effort!
Great spirits have always encountered violent opposition from mediocre minds. Albert Einstein
Thats easy, the shop around the corner from my place sells them. Just remember not to eat them with coke, or KAPOW! Mouth explodies!
Never fight naked, unless you're in prison...
wonderful, but I can use that arguments to say you don't know that unicorns don't exist. You don't know your baby can't fly. It IS scientific to doubt a conclusion if all the evidence so far has been non-repeatable hallucination.
A dextrorotatory dick. is that the same as Clinton's or is his levorotatory?
otherwise they would be sitting in a detention centre right now appealing their refusal of refugee status by the Australian Gumment. Bloody alien queue jumpers will not be tolerated.
Assides from the non sequetor, which applies regardless, did you read the article? If you had read it and the intro above, you would have noticed that the amino-acids not found on earth also are mostly "left-handed" which is not how they form in a lab.
Friends don't help friends install M$ junk.
Also, one must remember that a lot of the heavy metals that were present during earths' formation have sunk to the center of the earth, during it's big-ball-of-lava stage.
It stands to reason, then, that with no 'center' to sink to, those asteroids must be practically loaded with easy-to-access heavy/rare elements! Another big bonus - practically no gravity on the surface of an asteroid makes everything even easier.
I'd love to see this happen, but it probably won't during my lifetime.
Isn't Patriotism grand? Good on ya Michael -- I'm sure Aussie will become the 51st State any day now. No, really...!
prepare to face mod hell!!!!!!!!!!!!!!!1
If there is a catalyst, then it is possible that one isomer will be perferred. You are absoultly correct for non-catalyzed reactions - and you are probably more of a synthetic person than I am.
That's an excellent idea... as many others have mentioned, contamination is still an issue; your method substantially reduces it however.
Large rocks are hard to collect; dust particles are much easier. A probe is currently out there collecting them in aerogel.
Let's analyze your comment. You use stereotypes, name-calling and weak assumptions to make your attack. Your apparent grasp of logical concepts is not impressive. Bloody arrogant, indeed.
You could simply send probes to the Lagrange points. It is highly likely that each L point will contain a mass of rocks...the problem is that they could contain a mix of terrestrial (blown off by meteorite strikes) and extraterrestrial rocks. Theses points are much closer than the asteroid belt.
As for the asteroid belt and collision protection...not a problem. The asteroid belt is NOTHING like what you see on Star Wars movies. It is not a chaotic hoard of roaving rocks. There is a great deal of space between rocks and they are not wildly roaming about in the belt. You can easily (and we have done it every time we send out a deepspace probe to the outer planets) send a craft through the belt without coming anywhere near any rock.
Just pick a rock or two and send a probe. Your chances of finding anything are likely minor as it is doubtful that EVERY space rock is going to contain appreciable amounts of amino acids or their precursors.
In Bushworld, they struggle to keep church and state separate in Iraq as they increasingly merge the two in America.
Isn't the speed of light only 1.8 million miles per second? That would be about 6% of the speed of light, roughly. I'm not saying you are wrong. I'm just saying that they probably aren't going that fast. Something going that fast hitting the earth might have a bit more kick than they currently do.
God makes the rules. We may quibble about the mechanisms, whether God is a he or she, and whether the universe was made in an all-nighter or over billions of years, but one fact remains: Something or Someone layed out all of the ground rules by which our Universe exists. Those rules are still beyond our understanding, and represent a power greater than ourselves. Call it Jaweh, Vishnu, Allah, or Chaos, but THAT is God.
Never mix the study with the subject matter itself. If you talk to a Physicist long enough he sounds like a Theologist, and vice verse.
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
They are trying to something similar already:
http://stardust.jpl.nasa.gov/
This is 100% correct. Sucralose is chlorine-substituted sucrose, not a left-handed isomer.
Yes, but the problem often surfaces where the scientists "peer reviewing" your journal have political, financial, or other biases keeping them from being objective. The peer review process demands complete objectivity, as does science. If they don't have that, you can be discounted even though your hypotheses are valid.
I keep doing that.
;) )
I can accept 100k mph as possible. I doubt if they really are going that fast, although I don't have any figures as to the average speed.
All I remember is that we managed to get one ship on a comet recently. Couldn't have been going too fast. (No, I'm not thinking of the movie "Armageddon" either.