Panspermia

Ok, this is a bit of a tangent but this is a smart crowd and I’ve been wondering something.<p>Was reading about the Silurian hypothesis from NASA researchers, which talks about how hard it could be to detect a previous technological society in the geological record. (Harder than I’d assumed.) [1]<p>Given that — and climate change being top-of-mind — I was thinking about Venus and wondering: how certain&#x2F;uncertain are scientists that Venus’s greenhouse effect wasn’t caused by a technologically advanced society, a very long time ago?<p>From my understanding, it’s so hot there that anything we’ve sent has burned up rather quickly. If it’s indeed very difficult to detect a previous civilization in the geological record <i>on earth</i>, what does that say about Venus?<p>1: <a href="https:&#x2F;&#x2F;en.m.wikipedia.org&#x2F;wiki&#x2F;Silurian_hypothesis" rel="nofollow">https:&#x2F;&#x2F;en.m.wikipedia.org&#x2F;wiki&#x2F;Silurian_hypothesis</a>

It&#x27;s interesting to note that, regardless of actual origin of life, a significant exchange might have been occurring (or is still occurring) between Solar System bodies (judging by how we found a number of Martian meteorites on Earth). So if we find life elsewhere in the Solar System, it might be quite compatible.<p>The idea is mentioned in Kim Stanley Robinson&#x27;s &quot;2312&quot;, where simple organisms exist in Enceladus&#x27;s ocean, and some people inject them for fun (with neutral or mildly beneficial effects).

I, for one, have been busily working in my backyard launching nano-rockets filled with water bears that I&#x27;ve manipulated via CRISPR to contain encoded messages of funny dad jokes.

There’s an interesting paper mentioned: The DNA of Bacteria of the World Ocean and the Earth in Cosmic Dust at the International Space Station <a href="https:&#x2F;&#x2F;www.hindawi.com&#x2F;journals&#x2F;tswj&#x2F;2018&#x2F;7360147&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.hindawi.com&#x2F;journals&#x2F;tswj&#x2F;2018&#x2F;7360147&#x2F;</a>

The idea explained in a computer animated video <a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=kWChhdIgT6Q&amp;gl=BE" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=kWChhdIgT6Q&amp;gl=BE</a>

I don&#x27;t see it mentioned on wikipedia, but one tin-pot theory I heard once and quite liked was:<p>* The universe at the moment is on average large, cold and quite hostile to life.<p>* At some point in the past all the energy in the universe was concentrated roughly at one point<p>* So, in between, the universe was a soup of energy that would have been, on average, warm, comfortable and conducive to life.<p>It dovetails with this because it is a plausible &quot;why would life have evolved somewhere else but not here&quot; counterargument. I wouldn&#x27;t buy it though, it seems likely to me that earth&#x27;s life is a local phenomenon.

One argument that life is common is that life appeared very early on Earth, and so by inference Origin of Life is likely to be an easy process.<p>But there&#x27;s another possibility: perhaps panspermia is easy in the dense star cluster the Solar System formed in, which packed 1000 or more stars into a cubic parsec. In that case, if life originated early, it could then spread to all the other star systems in that cluster. This would amplify the statistical weight of &quot;early&quot; OoL. Most planets on which life gains a foothold would be those in which OoL happened to occur in this birth nursery, and then spread.<p>This concept has interesting implications for SETI and science fiction. Life might be extraordinarily rare or absent elsewhere in the universe, but there may still be thousands of other systems in our galaxy that were seeded along with ours. They&#x27;d be spread out now around a ~180 degree arc around the center of the galaxy.

I had a conversation with someone about cryonics a few years ago, and they brought up an ineresting problem with the viability of cell over long periods of time. DNA repair is an active process, and if frozen in Liquid Nitrogen, all molecular activity stops, yet radiation damage can still occur. It seems like on a long interstellar voyage, gamma rays and other cosmic rays would turn an organisms DNA into soup.

<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Directed_panspermia" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Directed_panspermia</a>

Is it possible that self replication was ignited at the time of heavy bombardment? It&#x27;s really strange how origin of Life on Earth is correlated with this time. One possibility might be that our planet was covered with ice at this time while constant bombardment should produce a lot of phase shifts and randomness, contributing to significant recombinations of available molecules in water. It&#x27;s a kind of top-down approach.

Check out Nick Lane&#x27;s videos on his theory of life origins on earth. Fascinating stuff.

A theory that can never be tested is as much a religion as any.

OP, did you just watch &quot;How the universe works&quot;?

This just pushes the problem of abiogenesis one step back.

My wikipedia-chain for the past hour and a half: <a href="https:&#x2F;&#x2F;hedwig.orenhazi.com&#x2F;misc&#x2F;nerdsniped.jpg" rel="nofollow">https:&#x2F;&#x2F;hedwig.orenhazi.com&#x2F;misc&#x2F;nerdsniped.jpg</a><p>I hope you&#x27;re happy.

I remember they used a “Panspermia” animation for Pantera’s cover of “Planet Caravan” back in 1994.<p><a href="https:&#x2F;&#x2F;youtu.be&#x2F;kWChhdIgT6Q" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;kWChhdIgT6Q</a>