Panspermia, not a viable explanation for the OOL

Panspermia, not a viable explanation for the OOL

https://reasonandscience.catsboard.com/t1362-panspermia-not-a-viable-explanation-for-the-ool

Blank and her NASA team  claimed that amino acids can survive a comet’s entrance into Earth’s atmosphere and subsequent surface impact. But this  presents a big problem. Calculations and measurements show that both events generate so much heat (atmosphere = 500°+ Centigrade while the collision = 1,000°+ Centigrade) that they break down the molecules into components useless for forming the building blocks of life molecules. This was confirmed by NASA when they sent the Stardust Spacecraft to the comet 81P Wild in 2004 to recover samples, which were returned to Earth and analyzed for organic molecules. The only amino acid indisputably detected in the sample was glycine at an abundance level of just 20 trillionths of a mol per cubic centimeter

Life chemistry demands homochirality (same chirality). Proteins cannot assemble unless all the chiralamino acids (20 out of the 21 bioactive amino acids are chiral) are either 100 percent left-handed or 100 percent right-handed. Likewise, DNA and RNA molecules cannot assemble unless all pentose sugars are 100 percent left-handed or right-handed. All organisms on Earth manifest only left-handed chiral amino acids and right-handed  pentose sugars. 7

A chiral excess of isoleucine exists in GRA 95229, indicating that some mechanism must produce it. But still it is questionable if this relatively low level of chiral excess in isoleucine can explain the origin of homochirality. A 14% surplus of one enantiomer is a far cry from the 100% required for living systems. 3

Life chemistry demands homochirality (same chirality). Proteins cannot assemble unless all the chiralamino acids (20 out of the 21 bioactive amino acids are chiral) are either 100 percent left-handed or 100 percent right-handed. Likewise, DNA and RNA molecules cannot assemble unless all pentose sugars are 100 percent left-handed or right-handed. All organisms on Earth manifest only left-handed chiral amino acids and right-handed  pentose sugars.

chiral excess in Earth’s oceans will not promote homochirality in life molecules, but, in fact, detracts from it. 6

a chiral excess of isoleucine exists in GRA 95229, indicating that some mechanism must produce it. But still it is questionable if this relatively low level of chiral excess in isoleucine can explain the origin of homochirality. A 14% surplus of one enantiomer is a far cry from the 100% required for living systems. 4

several pieces of evidence are deal-killers for one or both those theories. Among them: the richness of deuterium, which the Tagish Lake Meteorite and most comets have. Heavy hydrogen forms when water absorbs neutrons. That can happen only from an event that releases many neutrons. The tremendous earthquakes of the Global Flood likely produced that swarm of neutrons. An exploding planet between Mars and Jupiter could have produced such a swarm. But an interstellar meteor stream or dust or gas cloud could not. (The exploded planet theory has a deal-killer of its own, namely all the ice on the Moon and Mercury.)

So an interstellar origin defies logic and is well-nigh impossible. Without that, panspermia is equally impossible. 5

Objections to Panspermia

The full theory of panspermia requires two events to explain the presence of life on earth:

The generation of life outside the earth
The transfer of this life to earth

Many scientists have objected that the generation of life cannot occur, or have occurred, outside of a planetary environment, where heavier elements are plentiful. Almost the only elements present in interstellar space are hydrogen and helium--and the latter, being an inert or noble gas, is not a component of life in any form known to man.

The generation objection by itself would not destroy panspermia. But the transference event requires a transit through space, followed by a passage through the earth's atmosphere and then an impact on the ground or at sea. Either of these events is fraught with danger. The unprotected space outside of an atmosphere is subject to unfiltered radiation in various forms. These include the products of radioactive decay, cosmic rays (the highest-energy form of electromagnetic radiation known to man), and the stellar wind, a stream of particles that fly out from any star as it continuously burns. Even if any life forms could survive the spatial passage, it must then somehow penetrate the atmosphere and risk incineration from sheer friction, and then must survive the impact.

Recently a team of researchers at the Centre for Molecular Biophysics in France were able to simulate a meteoric entry by strapping rocks containing microfossils and laced with Chroococcidipsis, an unusually robust bacterium, to the heat shield of a rocket probe before it was launched and then ordered to re-enter the atmosphere. Though the microfossils remained after re-entry, the bacteria were all destroyed, and only their outlines remained. The investigators concluded that any bacteria or other micro-organisms in a meteorite would require at least 2 cm of rock covering to protect them. In fact, the experimental conditions seem to suggest that micro-organisms within an actual meteorite would require more shielding than 2 cm, because a typical meteorite enters the atmosphere at about twice the speed of the returning rocket probe.

Chemistry happens, and interesting molecules form in space; so what?  It’s not going to help the believers in naturalistic origin of life.  So they found glycine, the simplest and only non-chiral amino acid.  The biologists told the astronomers to look for life’s building blocks in space, because they were having such a hard time producing them on Earth.  They would need megatons of amino acids and nucleic acid bases to rain down on the Earth for any hope of getting successful concentrations, but then the precious cargo would be subject to rapid degradation by water, oxygen, UV light, and harmful cross-reactions.  Even then, they would be mixtures of left and right handed forms, with no desire nor power to organize themselves into astronomers who could invent weird science like this. 2

Life chemistry demands homochirality (same chirality). Proteins cannot assemble unless all the chiralamino acids (20 out of the 21 bioactive amino acids are chiral) are either 100  percent left-handed or 100 percent right-handed. Likewise, DNA and RNA molecules cannot assemble unless all pentose sugars are 100 percent left-handed or right-handed. All organisms on Earth manifest only left-handed chiral amino acids and right-handed  pentose sugars. 8

chiral excess in Earth’s oceans will not promote homochirality in life molecules, but, in fact, detracts from it. 9

1) http://www.reasons.org/articles/through-the-glass-darkly
2. http://creationsafaris.com/crev0803.htm
3. http://www.academia.edu/6811752/The_Fly_in_the_Ointment_Homochirality_and_Extraterrestrial_Origin-Of-Life_Theories
4. http://www.conservativenewsandviews.com/2012/10/22/creation/panspermia-really/
5. http://creationwiki.org/Panspermia
6. http://www.reasons.org/articles/through-the-glass-darkly
7. https://tnrtb.wordpress.com/2011/11/07/homochirality-and-the-origin-of-life/
8. http://www.academia.edu/6811752/The_Fly_in_the_Ointment_Homochirality_and_Extraterrestrial_Origin-Of-Life_Theories
9. http://www.reasons.org/articles/explanation-for-origin-of-lifes-molecular-handedness-is-insoluble

There is a unbridgeable gap between origin of life proposals, and the complexity of the biochemical processes in the cell to synthesize the building blocks for life.

http://reasonandscience.heavenforum.org/t1362-panspermia-not-a-viable-explanation-for-the-ool#3222



The amazing complexity to make DNA nucleobases

http://reasonandscience.heavenforum.org/t2028-origin-of-the-dna-double-helix#3426

Both nucleobases, Pyrimidines, and Purines had to begin to be produced prior when life began since they make up DNA - the molecule that stores genetic information. That means as well, that all enzymes used in the pathway to make the bases had to be present prior the supposed Last Universal Common Ancestor ( that's a fairy tale anyway, but for the argument, it doesn't matter )  For pyrimidines, six synthesis manufacturing/biosynthesis steps are required, and for purines, eleven.

The thrilling part is that just one of all these enzymes is staggeringly complex. David Goodsell writes: Aspartate carbamoyltransferase is fully as complex as any fine automobile in our familiar world. 

Take just a moment to ponder the immensity of this enzyme. The entire complex is composed of over 40,000 atoms, each of which plays a vital role. The handful of atoms that actually perform the chemical reaction are the central players. But they are not the only important atoms within the enzyme--every atom plays a supporting part. The atoms lining the surfaces between subunits are chosen to complement one another exactly, to orchestrate the shifting regulatory motions. The atoms covering the surface are carefully picked to interact optimally with water, ensuring that the enzyme doesn't form a pasty aggregate, but remains an individual, floating factory. And the thousands of interior atoms are chosen to fit like a jigsaw puzzle, interlocking into a sturdy framework. Aspartate carbamoyltransferase is fully as complex as any fine automobile in our familiar world. And, just as manufacturers invest a great deal of research and time into the design of an automobile, enzymes like aspartate carbamoyltransferase are finely tuned.

Beside this enzyme, all others, almost 20, had to be produced prebiotically, and then interconnected like in a factory assembly line, to make DNA nucleobases !!

There was no evolution. No natural selection. No mutations - nah nah  Charly won't provide the crutches to explain the feat.....

The only alternative to these biochemical processes would be, that the basic building blocks were readily available on a prebiotic earth. Glycine for instance is a indispensable substrate for pyrimidine nucleotide synthesis, and so - DNA - in cells. It  requires at least 5 biosynthetic steps and the respective enzymes to be synthesized. In a prebiotic earth, the only alternative would have been that glycine came from comets.

Comet contains glycine, key part of recipe for life 3
May 27, 2016
An important amino acid called glycine has been detected in a comet for the first time, supporting the theory that these cosmic bodies delivered the ingredients for life on Earth, researchers said Friday.
In addition to the simple amino acid glycine, the instrument also found phosphorus. The two are key components of DNA and cell membranes. "Demonstrating that comets are reservoirs of primitive material in the Solar System, and vessels that could have transported these vital ingredients to Earth, is one of the key goals of the Rosetta mission, and we are delighted with this result."

Panspermia, not a viable explanation for the OOL
http://reasonandscience.heavenforum.org/t1362-panspermia#1926

Chemistry happens, and interesting molecules form in space; so what?  It’s not going to help the believers in naturalistic origin of life.  So they found glycine, the simplest and only non-chiral amino acid.  The biologists told the astronomers to look for life’s building blocks in space, because they were having such a hard time producing them on Earth.  They would need megatons of amino acids and nucleic acid bases to rain down on the Earth for any hope of getting successful concentrations, but then the precious cargo would be subject to rapid degradation by water, oxygen, UV light, and harmful cross-reactions.  Even then, they would be mixtures of left and right handed forms, with no desire nor power to organize themselves into astronomers who could invent weird science like this.
.
Following the unresolved issues of nucleotide biosynthesis
http://reasonandscience.heavenforum.org/t2028-biosynthesis-of-the-dna-double-helix-evidence-of-design#3426

Glycine
http://reasonandscience.heavenforum.org/t1740-origin-of-the-canonical-twenty-amino-acids-required-for-life#5731