Washington Post: DNA building blocks found in meteorites

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http://www.washingtonpost.com/national/health-science/dna-building-blocks-found-in-meteorites/2011/08/08/gIQAzNe42I_story.html

“In laboratory experiments, Callahan and colleagues showed how the nucleobases could have formed inside meteorites. Simple chemical reactions involving ammonia, water and hydrogen cyanide — all ingredients found in meteorites — produced the wide range of nucleobases the scientists found in the space rocks.”

If it was so simple--meteorites or asteroids could spontaneously produce exotic nucleobases, why did Earth never form them?

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Added on Aug. 9, 2011:
Meteorites are post-solar, not pre-solar;
Mars meteorite contained DNA container

There is no good evidence that meteorites existed before the formation of our solar system, although theorists keep on saying they have such evidence. Meteorites existed after our solar system was formed, because meteorites contain numerous fossilized cells, tissues (note 1), and molecules. Again, theorists say the molecules are not biological remains as they existed in “pre-solar” meteorites while the same molecules are biological in origin if they exist in terrestrial fossils, no matter how complex or how essencial to DNA they were. In a word, “no fossil” can be allowed in meteorites. How could there be life before our solar system was formed?

Inconvenient facts: 1. Most meteorites contain fossils (note 1); 2. Mars meteorite ALH 84001 contains chromatin fibers which contained DNA (note 2).
Note 1: Edit [Moderator]: Link removed

Note 2: Edit [Moderator]: Link removed

1 Reply

@bewildered,

Very interesting article. Thanks.

It's been know for years that carbonaceous chondrites are associated with amino acids and other organic compounds, but nucleobases are a new one.

None of this lends any credence to the rest of your claims of course, but that's ok, it's interesting by itself.

0 Replies

@bewildered,

bewildered wrote:

There is no good evidence that meteorites existed before the formation of our solar system.

Meteorites are defined as meteors that have impacted Earth, as such, meteorites can not have existed before Earth. You need to be more precise in your usage of terms so that we can be sure to understand just how crazy your claims are.

Space debris (asteroids and comets and other such things) definitely existed before our solar system did because that's the stuff that our solar system is formed from. We can tell from the spectral signature of the sun that it contains heavy elements which can only form from accumulation of material from a previous supernova. Our sun is a third generation star. Likewise the planets, including Earth contain elements which could not have come from any other source.

bewildered wrote:

Meteorites existed after our solar system was formed, because meteorites contain numerous fossilized cells, tissues (note 1), and molecules.

No they don't. You just think they do, but that's not evidence.

bewildered wrote:

Inconvenient facts: 1. Most meteorites contain fossils (note 1)

Bzzzt. Wrong. Thanks for playing the game.

2 Replies

Added on Aug. 9, 2011:
Post-solar, ancient biological molecules in meteorites

Molecules found in meteorites are post-solar, not pre-solar. Also, they are not pre-biotic. They are remains of ancient biological molecules.

Farmer, have you ever eaten your words?

1 Reply

@rosborne979,

clever devil, I know it is meteoroids.

1 Reply

@rosborne979,

"Space debris (asteroids and comets and other such things) definitely existed before our solar system did because that's the stuff that our solar system is formed from. We can tell from the spectral signature of the sun that it contains heavy elements which can only form from accumulation of material from a previous supernova. Our sun is a third generation star. Likewise the planets, including Earth contain elements which could not have come from any other source."

Eat your words.

1 Reply

@bewildered,

bewildered wrote:

Molecules found in meteorites are post-solar, not pre-solar. Also, they are not pre-biotic. They are remains of ancient biological molecules.

Says who? Just you?

0 Replies

@bewildered,

bewildered wrote:

clever devil, I know it is meteoroids.

Sorry, but if you want to play with the big geeks you have to be precise.

0 Replies

@bewildered,

bewildered wrote:

"Space debris (asteroids and comets and other such things) definitely existed before our solar system did because that's the stuff that our solar system is formed from. We can tell from the spectral signature of the sun that it contains heavy elements which can only form from accumulation of material from a previous supernova. Our sun is a third generation star. Likewise the planets, including Earth contain elements which could not have come from any other source."

Eat your words.

That's nothing new. I'm just paraphrasing basic stellar evolution and solar system dynamics.

0 Replies

Added on Aug. 10, 2011:
Why new DNA nucleobases found in meteorites can be biological

NASA’s press release (note 1) claims that new nucleobases of DNA found in meteorites were produced in a completely “non-biological” reaction in space (note 2). That is wishful thinking, because one cannot rule out biological production of the new nucleobases.

To re-produce the new neuclobases in the lab, the researchers used “hydrogen cyanide, ammonia, and water” (note 2), which are common not only in the space, but also on Earth. All molecules of DNA can be produced both biologically and non-biologically. Modern life on Earth did not produce the new nucleobases does not mean that ancient life on Earth or on Mars did not produce them.

Note 1: NASA’s press release is at http://www.nasa.gov/topics/solarsystem/features/dna-meteorites.html

Note 2: Quoted paragraph from the above press release:

“Thirdly, the team found these nucleobases -- both the biological and non-biological ones -- were produced in a completely non-biological reaction. "In the lab, an identical suite of nucleobases and nucleobase analogs were generated in non-biological chemical reactions containing hydrogen cyanide, ammonia, and water. This provides a plausible mechanism for their synthesis in the asteroid parent bodies, and supports the notion that they are extraterrestrial," says Callahan.”

1 Reply

@bewildered,

bewildered wrote:

NASA’s press release (note 1) claims that new nucleobases of DNA found in meteorites were produced in a completely “non-biological” reaction in space (note 2). That is wishful thinking, because one cannot rule out biological production of the new nucleobases.

They weren't trying to rule it out. They were showing that it wasn't necessary.

0 Replies

Original post Edited:

That is wishful thinking, because
1. Earth does not produce them non-biologically.
2. they could be biologically produced by ancient life on Earth or on Mars.

1 Reply

@bewildered,

bewildered wrote:

That is wishful thinking, because
1. Earth does not produce them non-biologically.
2. they could be biologically produced by ancient life on Earth or on Mars.

Irrelevant. They could have been biologically produced by ancient life on Saturn's moon Titan, or Jupiter's moon Europa, or even by magic.

The article isn't trying to rule out things. It's only showing a path from non-biological reactions.

If you want to find something that supports your theory then you need find something that supports it, not something that is irrelevant to it.

0 Replies

Added on Aug. 11, 2011:
Why organic molecules in meteorites are post-biotic fossils

Amino acid molecules produced in the lab are 50% left handed and 50% right handed. However, amino acid molecules produced in animal bodies are over 50% left handed. This difference is a sure sign of life (note 1). This sign of life is found in organic molecules in meteorites (note 2). So, organic molecules in meteorites are post-biotic fossils.

Note 1: “Homochirality probably constitutes the most reliable indicator of the biological vs. abiotic origin of organic molecules.” http://www.esa.int/SPECIALS/ExoMars/SEMK39JJX7F_0.html

Note 2: “In the new research, the team reports finding excess left-handed isovaline (L-isovaline) in a much wider variety of carbon-rich meteorites.” http://www.nasa.gov/topics/solarsystem/features/left_hand_aminoacids.html

1 Reply

@bewildered,

Interesting articles: thanks.

Your conclusions are still crazy, but that's ok.

0 Replies

Washington Post: DNA building blocks found in meteorites

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