12 Aug 11
1 edit
http://lightyears.blogs.cnn.com/2011/08/11/dna-discovered-in-meteorites/?hpt=hp_c1
NASA researchers have found the building blocks of DNA, the genetic molecule that is essential to all life forms, in meteorites, pieces of space rock that have fallen to Earth. The discovery suggests that similar meteorites and comets may have impacted Earth and assisted in life formation here.
With minimal chance for contamination of the meteorite samples, scientists are confident that these meteorite specimens were formed in space. “People have been discovering components of DNA in meteorites since the 1960's, but researchers were unsure whether they were really created in space or if instead they came from contamination by terrestrial life,” Michael Callahan, lead author of the study on the discovery, said in a statement.
The research team analyzed twelve carbon rich meteorites, nine of which were from Antarctica, to positively identify the basic elements of the chemical compounds they extracted from the samples. Testing revealed adenine and guanine, two fundamental components of DNA called nucleobases.
12 Aug 11
Originally posted by wittywonkaya beat me to it🙂 Saw that and copied the link from CNN. That is going to throw a big kink in the creationist line that random chemical reactions would be too rare to have developed the big molecules leading to life.
http://lightyears.blogs.cnn.com/2011/08/11/dna-discovered-in-meteorites/?hpt=hp_c1
NASA researchers have found the building blocks of DNA, the genetic molecule that is essential to all life forms, in meteorites, pieces of space rock that have fallen to Earth. The discovery suggests that similar meteorites and comets may have impacted Earth and assis ...[text shortened]... Testing revealed adenine and guanine, two fundamental components of DNA called nucleobases.
If the earth has been seeded with the stuff of life, prebiotics, for millions of years the equation will tilt away from the random cycling of muck on earth to active injection of prebiotic material, a leg up on the randomness theory creationists love to bandy about.
Science 1. Creationists 0.
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12 Aug 11
Heck, astronomers have spotted organic molecules in gas clouds floating through space.
They have even worked out a possible chemistry of how they form.
Basically you find the organic molecules needed to form carbon based life everywhere
not too hot/radioactive/empty to hold them.
This will however do absolutely nothing to dissuade people who object to the science
on religious grounds as they don't care about reason, logic or evidence.
And btw Science is winning by allot more than 1 ;-)
13 Aug 11
Originally posted by wittywonkaSpectral signatures. Starlight passing through a cloud of dust and gas will be absorbed at specific frequencies depending on the chemicals that the cloud contains. Each atom and molecule has its own unique spectral signature, which acts rather like a fingerprint.
How would they have been able to see them from Earth? 🙄
13 Aug 11
2 edits
Originally posted by SoothfastBesides, the meteorites analysed are ones already landed on Earth, mostly in Antarctica where they are stored in ice.
Spectral signatures. Starlight passing through a cloud of dust and gas will be absorbed at specific frequencies depending on the chemicals that the cloud contains. Each atom and molecule has its own unique spectral signature, which acts rather like a fingerprint.
Organic molecules in space are detected by radio telescopes and IR telescopes used as spectrum analyzers. Each organic molecule has a specific spectrum in either radio wavelengths or IR or both. That way they can chart the organics in nebula clouds and such, stuff from exploded stars. The energy of the nova is more than enough to transform PAH's (Polycyclic Aromatic Hydrocarbons) to more complex organic molecules.
Here is one link about PAH's:
http://www.sciencedirect.com/science/article/pii/016811769504270U
14 Aug 11
Originally posted by wittywonkaSarcasm? Just what are you about with that post? You say Astronomer then ask how they could see the clouds from Earth? Are we supposed to believe you don't know what a telescope is?
Yeah, my written sarcasm skills are lacking these days.
Maybe I should have written [sarcasm] "..." [/sarcasm].
14 Aug 11
Originally posted by wittywonkaI thought you were being sarcastic, but...
Yeah, my written sarcasm skills are lacking these days.
Maybe I should have written [sarcasm] "..." [/sarcasm].
....I couldn't be 100 percent sure. 😉
Anyway I couldn't resist casting out a brief answer to the query for the benefit of anyone who blows by this forum who really doesn't know.
15 Aug 11
1 edit
Originally posted by wittywonkaThat is an interesting theory, obviously remnants of DNA could travel on an asteroid.
http://lightyears.blogs.cnn.com/2011/08/11/dna-discovered-in-meteorites/?hpt=hp_c1
NASA researchers have found the building blocks of DNA, the genetic molecule that is essential to all life forms, in meteorites, pieces of space rock that have fallen to Earth. The discovery suggests that similar meteorites and comets may have impacted Earth and assis Testing revealed adenine and guanine, two fundamental components of DNA called nucleobases.
How are they assuming that there is minimal chance of contamination?
If it passed through the atmosphere and hit the earth, seems like there is a very good chance of contamination. All types of bacteria, viruses and spores are floating around in the atmosphere all over the world. The chances of hitting one during the fall are pretty good I would think.
We need to capture an asteroid while it is still in space, that would be proof of the theory.
15 Aug 11
Originally posted by mlpriorA couple of points: One, the meteors and asteroids don't have bits and pieces of DNA, that would immediately imply the asteroids had some kind of life form start on it, while not impossible, highly unlikely given there would most likely be no liquid water or much of any liquid.
That is an interesting theory, obviously remnants of DNA could travel on an asteroid.
How are they assuming that there is minimal chance of contamination?
If it passed through the atmosphere and hit the earth, seems like there is a very good chance of contamination. All types of bacteria, viruses and spores are floating around in the atmosphere all ov ...[text shortened]...
We need to capture an asteroid while it is still in space, that would be proof of the theory.
Not impossible I suppose but don't hold your breath or quit your day job on this one. The bits and pieces of DNA that you think you are talking about is actually just some sub-components that have to come together way later to become RNA first then DNA.
The stuff in the asteroids and meteors are basic building blocks which, when properly combined, can over a long period of time on a liquid water world with energy input from sunshine, can end up as RNA and start copies going and then later converting to DNA.
And two, the contamination issue was taken care of by the fact that a lot of the original material in the meteorite when it lands on earth, is captured deep inside the meteorite as bits of organic material inside solid rock.
So they take a deep sample, say by slicing it in a pristine atmosphere or vacuum and then etching away a bit of the surface and only then doing an analysis of the inside contents of the meteorite.
Because of the rather short length of time it was burning up in the atmosphere, a minute at most, like an ablative shield, would have left the inside of the meteorite unscathed and any contamination would take millions of years to get deep inside the meteorite.
Most of the meteorites studied were taken from the ice deposits of Antarctica and date back maybe 10,000 years or so give or take a few thou, so was spared any grinding action of earthquakes and such, being now on the surface of the ice. Not enough time to have any process contaminate the center part of the meteorite. So it would be proven to be not contaminated.
15 Aug 11
Originally posted by sonhouseI was not implying life ON the asteroid, I said REMNANTS of DNA on the asteroid. I am fully aware of the chemical make up of DNA, thank you.
A couple of points: One, the meteors and asteroids don't have bits and pieces of DNA, that would immediately imply the asteroids had some kind of life form start on it, while not impossible, highly unlikely given there would most likely be no liquid water or much of any liquid.
Not impossible I suppose but don't hold your breath or quit your day job on ...[text shortened]... ss contaminate the center part of the meteorite. So it would be proven to be not contaminated.
It is possible that the meteorites picked up some airborne organisms during entry and then the organisms were lysed and driven into the meteorite during impact. If the functional groups (N base) were frozen, they would not degrade with time. The atmosphere is far from aseptic, even over the south pole.
Once again we do not see eye to eye, I take it that you are an engineer.
15 Aug 11
Originally posted by mlpriorBy 'remnants' of DNA I assume you mean former life, like a cell getting busted up by heat? If so, I'm thinking it would be impossible in the short time the meteorites lived on the ice in Antarctica to have penetrated deep enough to contaminate the sample all the way to the center. I think they could see differentiation of the organic products that way. If there was contamination, I would think the outer layer would have the most 'remnants' and progressing inwards a smaller and smaller fraction of these remnants. So it the 'remnant' fraction was uniform inside the rock or say the differentiation occurred only in the outer micron of the surface, there would be a really large differentiation that would drop off to zero as the uncontaminated material closer to the center was analyzed.
I was not implying life ON the asteroid, I said REMNANTS of DNA on the asteroid. I am fully aware of the chemical make up of DNA, thank you.
It is possible that the meteorites picked up some airborne organisms during entry and then the organisms were lysed and driven into the meteorite during impact. If the functional groups (N base) were frozen, they w ...[text shortened]... over the south pole.
Once again we do not see eye to eye, I take it that you are an engineer.
I think this way they can tell the actual probability a given sample could be considered contamination free.
I am an ion implant field service engineer, sort of between a technician and an engineer. My work has taken me to clean rooms all around the US and at Intel in Jerusalem for 4 years, one of my kids graduated from the Anglican International School there. We also played folk music at festivals from Elat in the south to the Kinneret in the north. On the shores of the kinneret there is the biggest folk festival in Israel, called 'Jacob's Ladder'. My family band played there 3 times.
Aren't you the guy who has those video's teaching some guitar positions or something?
15 Aug 11
Originally posted by sonhouseI would assume that the force of slamming into the earth at high speeds would cause some matter to be embedded into the meteorite on impact or from the air during the fall. The article references finding nucleic acid analogues, theorized to be a very early form of nucleic acid that is much less evolved than the current form. Although the analogue is not made in nature today, it could have been made early on and remnants still around where they were well preserved (Antarctica). The nucleic acid analogues could have predated the extremophiles associated with Archaea.
By 'remnants' of DNA I assume you mean former life, like a cell getting busted up by heat? If so, I'm thinking it would be impossible in the short time the meteorites lived on the ice in Antarctica to have penetrated deep enough to contaminate the sample all the way to the center. I think they could see differentiation of the organic products that way. If t ...[text shortened]... ren't you the guy who has those video's teaching some guitar positions or something?
I'm not saying that it is impossible to think that nucleic acid functional groups could travel on meteorites, seeding other planets with building blocks for life. I think it would be incorrect to state that you pulled a sample that was previously contaminated and present it as uncontaminated. They need to get a pure sample from space itself, or at least from the moon, if they are going to validate their theory.
Here is one of the author's journal articles, I don't have time to read it now, but maybe later in the week, sounds like it in relation to a recent meteorite impact:
http://science.gsfc.nasa.gov/691/analytical/PDF/Glavinetal2010.pdf
Sorry, I do not teach guitar, I don't even know how to play guitar.