Francis Crick and the theory of Directed panspermia

The discussion then follows an Occams Razor direction. If it happened out there, why couldnt it have happened here without the extraneous step of riding pre-life in on a comet? Simpler the better.

It's a network of molecules that, given a constant supply of certain molecules, can quickly and repeatedly reproduce itself because the set contains molecules which are catalysts to all the reactions that would produce the set. Given a high variation of molecules in high concentration these sets form with nearly guaranteed statistical probability. They can evolve by assimilating new molecules into the set. There's a lot more evidence than this but that's the basic idea.

Gunter von Kiedrowski[15], then at U. Freiburg in Germany, several years ago published work on a collectively autocatalytic set of two DNA hexamers that mutually ligated the two pairs of DNA trimers composing the two hexamers. Meanwhile, Reza Ghadiri at the Scripps Institute in La Jolla, California has made an autocatalytic peptide, Nature August 2 years ago [9,10], and nearly collectively autocatalytic sets more recently [11,12].

They emergy reliably in computer models, but I think it is still mostly theoretical.

I guess I find it a bit odd that nobody has yet been able to mix at least some obscure chemicals, under some specific conditions to produce at least some replicative molecule.

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I guess I find it a bit odd that nobody has yet been able to mix at least some obscure chemicals, under some specific conditions to produce at least some replicative molecule.

Didn't I just give some examples of this?

ligands that replicate, like the haem group, Alu, chlorophyll, xanthophylls, etc can autocatalyze and reverse (that is, act against a chemical gradient.

Clay based polymerization of lobg chain (metal) centered molecules have been created by surface chemistry reactions. How an RNA first developed

The first process, the Tropsch process creates a long chain organic alkane and (in the presence of N) forms easily a series of nucleotides.
These , with metals and using surface chemistry reactions, the chains polymerize. The cyclic formation is a fairly common structure in nature , all the way from complex chain and "leaf " silicates to organics.
All that wasneeded was an initial atmosphere supersat in H2 and in a reducing environmenta. (And, we have evidence of these from early pyrite layers in and around the Isua and Newfoundland shales ). Pyrite is a mineral (fools gold) that forms in reducing environments.
As far as "not doing it" stuh's refs were a few of the literature on polymerization, ligands and autocatalysis.

Polycyclic Aromatic Hydrocarbons, which are stable as hell, are observable throughout the universe, from examples occurring naturally and through human intervention right here on earth, to comet dust, to the spectra of distant stars. They tend to form ordered, plate-like stacks of themselves, and in UV-irradiated aqueous solution have an affinity for amino acids, which stick to the stacks of plates. As they accrete, the space between these PAH layers is 0.34 billionths of a meter, which just happens to be precisely the distance between the ladder-like rungs of a DNA or RNA molecule. Given amino acids and long-chain polymers, protocellular membrane formation is no big deal, thats what Lipids, particularly Amphiphilic Lipids, are all about. As a simple, abiotic replicative mechanism, first at the molecular level, then, through accretion and chemical interaction, into ever more and more complex and diverse protobiotic compounds, that this phenomenon would be a logical precursor for the development both of RNA/DNA and prokaryotes is a notion which is a helluva strong candidate.