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Possible exposure of Earth to dense interstellar medium 2-3M years ago

nature.com

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Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#51

Post by barfbagginus »

pvaldes wrote: post #40
barfbagginus wrote: post #10

Why does this make me feel a little dirty and exposed ? Like, who knows what kinda alien DNA strands or spores are carried by the ISM?! I wonder if it would be possible to track biodiversity increases caused by the transit? Assuming there is biological material in the ISM, perhaps some of it made it into our biosphere! Very fun!

> what kinda alien DNA strands or spores are carried by the ISM? None that we are aware (and would be fried by the earth atmosphere probably). > Would be possible to track biodiversity increases caused by the transit An entirely new set of new forms of life appearing from nowhere and without any known ancestor in a small line of the "evolutive script" would not be missed. This is the opposite that we observe in that…

And I think that you're misunderstanding what I meant by a impact on the biosphere.

We wouldn't see all new species. We might see some new genes in a few species, which would have started arriving around 3 million years ago in the genomic record, and would not be explained by the ordinary arrival of new genes through mutations, either because the arrival rate would be too high or the genes arriving would be too different.

So the idea would be to think up genomic experiments and metrics that would be able to detect the arrival of exobiological material 3 million years ago, assuming that the effect would be very attenuated.

Again I think that serious geneticists and xenobiologists would have fun brainstorming ideas here. I just want to be a fly on the wall for that conversation, lol.

Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#52

Post by barfbagginus »

imiric wrote: post #27
barfbagginus wrote: post #10

Why does this make me feel a little dirty and exposed ? Like, who knows what kinda alien DNA strands or spores are carried by the ISM?! I wonder if it would be possible to track biodiversity increases caused by the transit? Assuming there is biological material in the ISM, perhaps some of it made it into our biosphere! Very fun!

If you accept that we're all made of stardust, with a little sprinkling of ISM, it should make you feel more connected to the universe, not less. :)

The more I think about it the more I agree with you. I don't know why I initially felt unsettled but now that I'm thinking we might be able to actually detect if it happened (through advanced genomics techniques), I am starting to warm up to the theory.

There's even a fun tie-in with stoned ape theory (which I don't endorse, but is a fun theory). In one version of the theory, humans eat magic mushrooms and become conscious or develop higher thought. In the ISM version, magic mushroom spores - or the genes that make them psychoactive - were seeded from the ISM three million years ago, leading to the evolution of homo erectus and homo sapiens.

This is a fun theory because it would be easy to falsify with a an experiment showing that magic mushrooms evolved their hallucinatory properties much longer than 3 million years ago. But note that you'd have to do so xenogenomic theory, to control for the possibility that the material came in from the ism itself as much older than 3 million years. Such material would show terrestrial genomic age metrics, which could make us think magic mushrooms evolved long ago on the earth, when in fact it evolved in another biosphere.

Anyways, you're right! This IS making me feel more connected to the universe!

Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#53

Post by barfbagginus »

dylan604 wrote: post #14
barfbagginus wrote: post #10

Why does this make me feel a little dirty and exposed ? Like, who knows what kinda alien DNA strands or spores are carried by the ISM?! I wonder if it would be possible to track biodiversity increases caused by the transit? Assuming there is biological material in the ISM, perhaps some of it made it into our biosphere! Very fun!

Maybe it was a large cloud of mushroom spores: https://en.wikipedia.org/wiki/Panspermia

This is an amazing idea! In my response to imiric, I detail an ICM Panspermia version of the Stoned Ape Theory, and hypothesize that we could use genomic dating techniques to experimentally falsify the theory (which is probably false because we probably had magic mushrooms for many millions of years). That makes it a fun theory to work with!

Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#54

Post by FooBarBizBazz »

noobermin wrote: post #42

Just a comment, I sent this to my advisor who was an astrophysicist a few years back (he and I are in plasma physics today) and here's something he pointed out, "[...]Abraham Loeb is about as controversial of a figure in astronomy as you can find. He is also the head of a UFO monitoring project and he still insists that the rod like object that telescopes saw pass through the solar system about a decade ago had an ex…

> the rod like object that telescopes saw pass through the solar system about a decade ago had an extraterrestrial origin.

I know what you mean -- "it's an alien artifact/spaceship!" -- but, literally, the sentence is true, no? It did not originate on Earth.

Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#55

Post by FooBarBizBazz »

profsummergig wrote: post #20

Anyone here read "Neck of the Giraffe"? He hypothesizes that cosmic ray bursts are responsible for mutational leaps in evolution. This seems similar.

The timing does seem to roughly match first known tool use in Homo habilis, if my Googling serves me well.

Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#56

Post by [deleted] »

thegrim33 wrote: post #50
noobermin wrote: post #42

Just a comment, I sent this to my advisor who was an astrophysicist a few years back (he and I are in plasma physics today) and here's something he pointed out, "[...]Abraham Loeb is about as controversial of a figure in astronomy as you can find. He is also the head of a UFO monitoring project and he still insists that the rod like object that telescopes saw pass through the solar system about a decade ago had an ex…

Can you believe that Galileo guy? What a crank. What a controversial figure. He actually insists that the Earth goes around the Sun. That's not science, that's just a madman, all our scientists know that the truth is the other way around. Don't read this new paper he wrote guys, look at the controversy surrounding him. Take from this what you will.

[deleted]

Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#57

Post by mlhpdx »

itishappy wrote: post #46
mlhpdx wrote: post #22

I wonder what effect this would have had on the sun itself — not like blowing in a fire, apparently.

None! The Sun has a forcefield called the heliosphere to protect it, and this protects the planets as well. This paper is arguing that the interstellar medium may have been dense enough to shrink the heliosphere to within the orbit of some planets, but it'd take a helluva lot more to shrink it down to the Sun's surface. https://en.wikipedia.org/wiki/Heliosphere

I understand, but given the dramatic change I'd expect some things to "bend" a little. Perhaps literally, like solar flares? Does "holding them closer" increase/decrease surface temperature?

Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#58

Post by dig1 »

thegrim33 wrote: post #50
noobermin wrote: post #42

Just a comment, I sent this to my advisor who was an astrophysicist a few years back (he and I are in plasma physics today) and here's something he pointed out, "[...]Abraham Loeb is about as controversial of a figure in astronomy as you can find. He is also the head of a UFO monitoring project and he still insists that the rod like object that telescopes saw pass through the solar system about a decade ago had an ex…

Can you believe that Galileo guy? What a crank. What a controversial figure. He actually insists that the Earth goes around the Sun. That's not science, that's just a madman, all our scientists know that the truth is the other way around. Don't read this new paper he wrote guys, look at the controversy surrounding him. Take from this what you will.

I learned to keep an open mind for even the craziest ideas - not because they sound funny, but because my mind might not comprehend them yet. Remember that Einstein was ridiculed for years by respective physicists [1]. At some point, Lord Kelvin even said physics was no longer attractive because there was nothing to discover (around 1900).

[1] https://daily.jstor.org/why-no-one-believed-einstein/

Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#59

Post by atombender »

thegrim33 wrote: post #50
noobermin wrote: post #42

Just a comment, I sent this to my advisor who was an astrophysicist a few years back (he and I are in plasma physics today) and here's something he pointed out, "[...]Abraham Loeb is about as controversial of a figure in astronomy as you can find. He is also the head of a UFO monitoring project and he still insists that the rod like object that telescopes saw pass through the solar system about a decade ago had an ex…

Can you believe that Galileo guy? What a crank. What a controversial figure. He actually insists that the Earth goes around the Sun. That's not science, that's just a madman, all our scientists know that the truth is the other way around. Don't read this new paper he wrote guys, look at the controversy surrounding him. Take from this what you will.

Counter-counterpoint: "They laughed at Columbus, they laughed at Fulton, they laughed at the Wright Brothers. But they also laughed at Bozo the Clown." — Carl Sagan, Broca's Brain (1979).

Re: Possible exposure of Earth to dense interstellar medium 2-3M years ago

#60

Post by pvaldes »

barfbagginus wrote: post #51
pvaldes wrote: post #40

Earlier quoted context omitted.

> what kinda alien DNA strands or spores are carried by the ISM? None that we are aware (and would be fried by the earth atmosphere probably). > Would be possible to track biodiversity increases caused by the transit An entirely new set of new forms of life appearing from nowhere and without any known ancestor in a small line of the "evolutive script" would not be missed. This is the opposite that we observe in that…

And I think that you're misunderstanding what I meant by a impact on the biosphere. We wouldn't see all new species. We might see some new genes in a few species, which would have started arriving around 3 million years ago in the genomic record, and would not be explained by the ordinary arrival of new genes through mutations, either because the arrival rate would be too high or the genes arriving would be too diffe…

The problem is that people confuse science with science fiction. Is the same problem each time somebody says the name "spider" here. Oh "Children of time" tell us all about how smart are spiders"... hem. Not.

There aren't known spores found out of earth. Only on the books. But histories in those books aren't real. Biology is real.

There is not any reason to assume that a earth fungus or a fern could made a spore able to survive in a rock in the vacuum of space for thousands of years. And the reentry in the atmosphere would reduce it to ashes at the end. Super-spores from entirely new types of organisms would be spotted by taxonomists.

Those hypothetical "genomic experiments" to modify things extant yet could only happen in a limited amount of individuals.

Most probably they would never work. Think in a computer program and paste some code at a random position of characters. Maybe in the middle of a word. The probability that the program still keeps running after that is very low. The line would need to fall exactly between two closed blocks. DNA is more complicated that computer programs. You can't just introduce random genes here and there unless you have genetic scissors for exactly this problem (we have this tool but for a limited number of cases), and know exactly where and how.

As those life beings would be defective the modifications would be diluted first on a much bigger population, and cleaned by evolution or predators soon after that.

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