Re: OT: Natural recycling at the origin of life

On 27/03/2024 11:39, Jan Panteltje wrote:

On a sunny day (Tue, 26 Mar 2024 16:13:50 +0000) it happened Martin Brown
<'''newspam'''@nonad.co.uk> wrote in <utus80$1tlii$1@dont-email.me>:
 

On 26/03/2024 04:13, Jan Panteltje wrote:

Natural recycling at the origin of life
   https://www.sciencedaily.com/releases/2024/03/240322145524.htm
Source:
   Ludwig-Maximilians-Universität München
Summary:
   How was complex life able to develop on the inhospitable early Earth?
   At the beginning there must have been ribonucleic acid (RNA) to carry the first genetic information.
   To build up complexity in their sequences, these biomolecules need to release water.
   On the early Earth, which was largely covered in seawater, that was not so easy to do.
>
So, simple :-)

>
Given how quickly a misfolded protein managed to propagate as BSE when
they scrimped on the cooking for cannibalistic cattle feed I suspect
that self replicating RNA, proteins and peptides are fairly common.
>
However, life might still need a fair bit of luck to get started ab
initio from entirely inorganic but common chemicals in molecular clouds.

 Na, I think it is a natural process, happening all over the universe here conditions allow..

I think it is a bit more specialised than that. You need a planet that has something like the three phases of water all present (other solvents may be possible). Water is almost unique in that it's solid phase floats and protects the bulk liquid of oceans from freezing solid.
If we find life independently evolved on any of the other solar system planest that have or once had liquid water then life is likely to be extremely common (but complex cellular life and in particular intelligent life could still be rare). We are the result of an arms race between competing species for food with animals at the top of the chain.

One unusual feature of the Earth-Moon system is that it had large and
variable tides with a monthly cycle (Moon orbited us closer and faster
in the distant past). This has the effect of making rock pools that
isolate from bulk seawater for variable lengths of time up to half a
month so that the liquid can concentrate (and get warm in the sun).

>
Then us, then chips, AI, what's next?

>
Fermi's Paradox suggests we are amongst the first in our galaxy to get
this far. Otherwise robotic alien probes would be everywhere by now.

 There are so many stars and galaxies, our 'window of time' where we can even do radio transmissions and sent something into space
versus there 'window of time' + travel time for spacecraft would need to overlap so the things would arrive here now and we can detect them..
Hard to detect too, very small.
And may not look alike anything _we_ put into space.

Even so we are the children of a third or fourth generation star.
There has been about 5-6 billion years for a civilisation around a previous generation star to have sent out probes assuming that their evolution was similar. Their probes should be here now...

 

Incidentally we may be able to detect industrialised civilisations at a
truly great distance if they follow the same path as we did.
>
Observing CFC's in the high atmosphere can pretty much only come from a
civilisation that has mastered organofluorine chemistry. Fluorine is
just too reactive and calcium fluoride so incredibly insoluble that it
is all scavenged into an inert form very quickly even if some occurs in
vulcanism. You have to separate it electrolytically from a molten salt
eutectic mix (scary stuff it is too).

 Absolutely, was some references to that on one of the sci sites I read every day..
Also there are great programs on German channels on Astra1 satellite that go into it,
show equipment, videos and shots taken by various spacecraft and professors talking about what they found.

The list of chemicals in molecular clouds is getting very long and suggestively contains a high proportion of certain common amino acids with the most duplicated/redundant codes in DNA.
Buckminster Fullerenes were seen in space as "dust" of unknown composition long before they were discovered on Earth. Amazingly you can extract them from common black soot using benzene but nobody ever did!
--
Martin Brown