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It contains nucleobases. But does it contain ribose, or ribose linked to the nucleobases, or to phosphates? And more generally, does it also contain a grab ba
by pfdietz 8mo ago
It contains nucleobases. But does it contain ribose, or ribose linked to the nucleobases, or to phosphates? And more generally, does it also contain a grab bag of related chemicals that are not building blocks? The existence of such blocks as minor constituents of a soup of random chemicals doesn't mean much, especially as the concentration of any such constituent declines exponentially with its complexity.
- ceejayoz 8mo agohttps://www.nasa.gov/missions/osiris-rex/sugars-gum-stardust-found-in-nasas-asteroid-bennu-samples/ https://www.nasa.gov/missions/osiris-rex/sugars-gum-stardust... > The five-carbon sugar ribose and, for the first time in an extraterrestrial sample, six-carbon glucose were found. The soup does matter, as does finding that the ingredients are everywhere.
- pfdietz 8mo agoFinding exponentially decreasing amounts of specific chemicals is about as informative as finding short words in strings of random letters.
- ceejayoz 8mo agoFinding short words in strings of random letters at least establishes the existence of letters and words. It doesn't demonstrate the existence of Shakespeare's works, but it's a building block that's good to know exists.
- pfdietz 8mo agoAll it means is you can say "if life is rare, it's not because these specific small chemicals can't be produced". Which is a rather weak thing to say. It doesn't imply life isn't rare, or that further advancement the existence of these small building blocks is easy or inevitable.
- ceejayoz 8mo ago> All it means is you can say "if life is rare, it's not because these specific small chemicals can't be produced". This is absolutely a good finding to have in your pocket.
- pfdietz 8mo ago"Good"? Ok, if it makes you feel better. But scientifically, it doesn't do much.
- kakacik 8mo agoWhats your problem with this topic? Highly confronting posts about nothing. Iterative approach to science seems foreign here.
- pfdietz 8mo agoThere's a tremendous amount of confidently stated bullshit on the issue of OoL that I have long since lost all patience with. What's your problem with the debunking of falsehood?
- ceejayoz 8mo agoYou asked "does it contain ribose"; I answered (with a reputable source) in the affirmative. Where's the falsehood?
- pfdietz 8mo agoI also asked about other things you have conveniently forgotten to mention there. The overarching falsehood is that identification of biologically relevant molecules at 200 ppb levels, in a soup of tens of thousands of other chemicals, moves the needle any in figuring out OoL.
- pixl97 8mo ago
- HarHarVeryFunny 8mo agoIt's a sample of one, but I think the takeaway is just that if the nucleobases are present on a random asteroid then they probably commonly occur. Of course as you note it takes a lot more than that to form these into nucleic acids. I would guess there is a more primitive stage in the emergence of life where self-replicating soups (Kaufmann: metabolisms), including things like nucleobases and amino acids, capable of collective replication/expansion exist, before we get anything as sophisticated as nucleic acids and structural encoding.