[HN Gopher] Organic molecule compositions in samples of asteroid...
       ___________________________________________________________________
        
       Organic molecule compositions in samples of asteroid Ryugu
        
       Author : perihelions
       Score  : 90 points
       Date   : 2023-02-25 09:49 UTC (13 hours ago)
        
 (HTM) web link (global.jaxa.jp)
 (TXT) w3m dump (global.jaxa.jp)
        
       | apienx wrote:
       | > "The diversity of soluble organic molecules detected in the
       | Ryugu samples is comparable to the diversity of organic molecules
       | found in carbonaceous meteorites. However, the molecular
       | distribution of low-molecular-weight organic compounds is
       | relatively low, similar to the distribution of organic matter in
       | carbonaceous meteorites that have been strongly affected by
       | aqueous alteration. This is also consistent with mineralogical
       | characteristics revealed by the initial analysis teams."
       | 
       | So there's a class of meteorites, carbonaceous chondrites that
       | have up to 3% of organic matter. 5% of all meteorites belong to
       | this class. The Hayabusa2 samples have the same level of organic
       | matter.
       | 
       | Cool. A new rock. But the cooler part is that these rocks were
       | likely exposed to water.
        
         | sandworm101 wrote:
         | >> But the cooler part is that these rocks were likely exposed
         | to water.
         | 
         | Water is everywhere in space. Only amongst the inner planets is
         | it baked away by the heat of the sun. Out past Jupiter, most
         | every rock seems to have substantial water content. Most of
         | that is ice, but any source of heat turns that into water for a
         | time. Two asteroids colliding would produce some liquid water
         | in their interiors, long enough for some organic chemistry to
         | happen.
        
           | _a_a_a_ wrote:
           | Umm, I don't know but would guess water-ice sublimes over
           | time in a vacuum.
        
             | idlewords wrote:
             | The rings of Saturn are almost entirely little chunks of
             | water ice, and they are stable over many hundreds of
             | millions of years. Cold ice (below about 150K) has a very
             | low vapor pressure.
        
       | perardi wrote:
       | Related reading: the Murchison meteorite.
       | 
       | https://en.wikipedia.org/wiki/Murchison_meteorite
       | 
       | It's an extensively researched meteorite that is just full of
       | organic molecules.
        
       | gremlinsinc wrote:
       | Thought experiment, anyone wonder what would happen if we started
       | space mining, and all of a sudden we started finding fossils in
       | asteroids? Like they're bits from ancient worlds that had life on
       | them? Perhaps feasible in a universe just 15 billion years old,
       | that things recycle and get moved around, and on a long enough
       | time scale parts of earth could be asteroids in a far off galaxy,
       | that isn't the milky way, long after our sun supernova's.
        
       | TEP_Kim_Il_Sung wrote:
       | [flagged]
        
         | peteradio wrote:
         | [flagged]
        
         | prox wrote:
         | There are pretty free range as well!
        
       | madaxe_again wrote:
       | The fluorescence test showing racemic mixtures of the enantiomers
       | is maybe the most significant datum - we kinda knew they had a
       | whole bunch of hydrocarbons from distant observation
       | spectrography, but the demonstration of an abiotic origin is a -
       | for panspermia and a + for abiogenesis.
        
         | fit2rule wrote:
         | [dead]
        
         | doitLP wrote:
         | How can we be sure it's of abiotic origin?
        
           | dvh wrote:
           | >left and right structures were present at approximately 1:1
        
           | nicolaslegland wrote:
           | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6027462/ TL;DR:
           | Biotic implies L-chirality. Ryugu exhibits balanced
           | chirality.
        
             | kevviiinn wrote:
             | Earth biotic origin implies L, I think it is theoretically
             | possible if life developed elsewhere that other enzymes may
             | preference R. AFAIK our enzymes are generally conserved
             | throughout life
        
               | madaxe_again wrote:
               | Indeed. Asimov's "Left hand of the electron" has an essay
               | which explores and explains why life inevitably ends up
               | with a chiral preference.
        
             | _a_a_a_ wrote:
             | "Biotic implies L-chirality" on this planet sure, but it's
             | one data point to extrapolate from. It's not enought.
        
       ___________________________________________________________________
       (page generated 2023-02-25 23:01 UTC)