
Panspermia - dyukqu
https://en.wikipedia.org/wiki/Panspermia
======
gdubs
Ok, this is a bit of a tangent but this is a smart crowd and I’ve been
wondering something.

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]

Given that — and climate change being top-of-mind — I was thinking about Venus
and wondering: how certain/uncertain are scientists that Venus’s greenhouse
effect wasn’t caused by a technologically advanced society, a very long time
ago?

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 _on earth_ , what does that say about
Venus?

1:
[https://en.m.wikipedia.org/wiki/Silurian_hypothesis](https://en.m.wikipedia.org/wiki/Silurian_hypothesis)

~~~
marcosdumay
All the carbon that we are releasing into the atmosphere was there at the
beginning, and was taken out by life. So I do think it's quite unlikely that a
civilization can appear in a planet that has enough carbon on its crust to
make it completely unsuitable for life.

~~~
gdubs
Interesting - could you expand on this a little further?

(Edit: sounds like there’s been recent research suggesting there was a decent
window of time where life might have had a chance to appear on Venus:
[https://www.scientificamerican.com/article/hellish-venus-
mig...](https://www.scientificamerican.com/article/hellish-venus-might-have-
been-habitable-for-billions-of-years/))

~~~
marcosdumay
Yeah, I didn't take the Sun heating up into account. Whatever you take from
astronomers is going to be better based (and take more factor into account)
than my speculation.

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gattr
It'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.

The idea is mentioned in Kim Stanley Robinson's "2312", where simple organisms
exist in Enceladus's ocean, and some people inject them for fun (with neutral
or mildly beneficial effects).

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

~~~
bencollier49
But then, disaster strikes!

It transpires that when encoded into quaternary, and thence to base pairs, the
joke "What lies at the bottom of the sea, shivering? A nervous wreck!" encodes
a viral sequence for a novel but entirely deadly pneumatic disease.

When one of the rockets misfires and detonates in a Bernard Matthews turkey
farm, all human life on this planet is quickly extinguished.

100 million years later, a crashed alien spacecraft is discovered by the
inhabitants of Gliese 15s, triggering a cultural revolution involving terrible
puns and mildly amusing logical inconsistencies.

------
lelf
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
[https://www.hindawi.com/journals/tswj/2018/7360147/](https://www.hindawi.com/journals/tswj/2018/7360147/)

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toolslive
The idea explained in a computer animated video
[https://www.youtube.com/watch?v=kWChhdIgT6Q&gl=BE](https://www.youtube.com/watch?v=kWChhdIgT6Q&gl=BE)

~~~
lanna
The source used in the music video:
[https://archive.org/details/sims_panspermia_1990](https://archive.org/details/sims_panspermia_1990)

------
roenxi
I don't see it mentioned on wikipedia, but one tin-pot theory I heard once and
quite liked was:

* The universe at the moment is on average large, cold and quite hostile to life.

* At some point in the past all the energy in the universe was concentrated roughly at one point

* So, in between, the universe was a soup of energy that would have been, on average, warm, comfortable and conducive to life.

It dovetails with this because it is a plausible "why would life have evolved
somewhere else but not here" counterargument. I wouldn't buy it though, it
seems likely to me that earth's life is a local phenomenon.

~~~
paxys
From
[https://en.wikipedia.org/wiki/Chronology_of_the_universe](https://en.wikipedia.org/wiki/Chronology_of_the_universe):

> Between about 10 and 17 million years the universe's average temperature was
> suitable for liquid water (273 – 373K) and there has been speculation
> whether rocky planets or indeed life could have arisen briefly, since
> statistically a tiny part of the universe could have had different
> conditions from the rest, and gained warmth from the universe as a whole.

~~~
quickthrower2
But temperature alone isn't sufficient for life as we know it. Here on Earth
we enjoy an atmosphere providing us with oxygen, a large planet protecting us
from most meteor impacts, and a magnetic shield against radiation.

~~~
Thiez
Life didn't start out breathing oxygen, oxygen was actually a waste product
and the introduction of oxygen into the atmosphere was a disaster for a lot of
the life existing at that time...
[https://en.m.wikipedia.org/wiki/Great_Oxygenation_Event](https://en.m.wikipedia.org/wiki/Great_Oxygenation_Event)

------
pfdietz
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.

But there'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 "early" 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.

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'd be spread out now around a ~180 degree arc around the center
of the galaxy.

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pontifier
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.

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jajag
[https://en.wikipedia.org/wiki/Directed_panspermia](https://en.wikipedia.org/wiki/Directed_panspermia)

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novaRom
Is it possible that self replication was ignited at the time of heavy
bombardment? It'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's a kind of top-down approach.

------
locusofself
Check out Nick Lane's videos on his theory of life origins on earth.
Fascinating stuff.

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

~~~
erikpukinskis
I don’t get it... how is this a religion? Doesn’t a religion set out rules for
living and have weekly services and stuff?

Also isn’t a theory a hypothesis that has already been tested and supported
with evidence?

~~~
hossbeast
Religion is choosing to believe that something is true without evidence.

~~~
erikpukinskis
I don’t think that’s right. Here are some definitions from Google:

the belief in and worship of a superhuman controlling power, especially a
personal God or gods.

a particular system of faith and worship.

a pursuit or interest to which someone ascribes supreme importance.

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epse
OP, did you just watch "How the universe works"?

~~~
dyukqu
:-) Nope, I was reading an article: _The Milky Way Could Be Spreading Life
From Star to Star_ -> [https://www.universetoday.com/140223/the-milky-way-
could-be-...](https://www.universetoday.com/140223/the-milky-way-could-be-
spreading-life-from-star-to-star/)

------
EGreg
This just pushes the problem of abiogenesis one step back.

~~~
memebox3v
I think some believers see a steady state universe. Life then becomes a
boltzman brain. But I think panspermia is likely a thing _and_ I think life
naturally arises in open dissipative systems. Get a rock, water, and a heat
source and wait a few million years...

~~~
otabdeveloper2
> Get a rock, water, and a heat source and wait a few million years...

And you get a warm, wet rock.

Statistics, probability theory and physics don't work like that. You can't
arrive at the conclusion by stating a premise and wishful thinking.

~~~
memebox3v
Why does everyone claim to know things they don't know? The more I know the
more stupid popular opinion becomes.

[https://en.m.wikipedia.org/wiki/Ilya_Prigogine](https://en.m.wikipedia.org/wiki/Ilya_Prigogine)

~~~
darkerside
I think what's missing from your closed system is some kind of variation to
induce change. Earth might not have enjoyed life without the rotation and
revolution of the Earth generating conductive (and other) currents in the air
and water.

Side note, I think you could make stronger points by not distracting with that
kind of off-putting sarcasm.

------
ohazi
My wikipedia-chain for the past hour and a half:
[https://hedwig.orenhazi.com/misc/nerdsniped.jpg](https://hedwig.orenhazi.com/misc/nerdsniped.jpg)

I hope you're happy.

~~~
snarfy
I see that list and all I see are purple links. It's still early :)

[https://en.wikipedia.org/wiki/Geon_%28physics%29](https://en.wikipedia.org/wiki/Geon_%28physics%29)

[https://en.wikipedia.org/wiki/One-
electron_universe](https://en.wikipedia.org/wiki/One-electron_universe)

[https://en.wikipedia.org/wiki/Standard_Model](https://en.wikipedia.org/wiki/Standard_Model)

[https://en.wikipedia.org/wiki/Spin_%28physics%29](https://en.wikipedia.org/wiki/Spin_%28physics%29)

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ErikAugust
I remember they used a “Panspermia” animation for Pantera’s cover of “Planet
Caravan” back in 1994.

[https://youtu.be/kWChhdIgT6Q](https://youtu.be/kWChhdIgT6Q)

