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Signs of Two Gases In Clouds of Venus Could Indicate Life, Scientists Say (theguardian.com) 39
Astronomers say they've detected two gases that could indicate the presence of life forms lurking in the clouds of Venus. The Guardian reports: Findings presented at the national astronomy meeting in Hull on Wednesday bolster evidence for a pungent gas, phosphine, whose presence on Venus has been fiercely disputed. A separate team revealed the tentative detection of ammonia, which on Earth is primarily produced by biological activity and industrial processes, and whose presence on Venus scientists said could not readily be explained by known atmospheric or geological phenomena. "It could be that if Venus went through a warm, wet phase in the past then as runaway global warming took effect [life] would have evolved to survive in the only niche left to it -- the clouds," said Dr Dave Clements, a reader in astrophysics at Imperial College London, told the meeting. "Our findings suggest that when the atmosphere is bathed in sunlight the phosphine is destroyed," Clements said. "All that we can say is that phosphine is there. We don't know what's producing it. It may be chemistry that we don't understand. Or possibly life."
In a second talk, Prof Jane Greaves, an astronomer at Cardiff University, presented preliminary observations from the Green Bank telescope indicating ammonia, which on Earth is made through either industrial processes or by nitrogen-converting bacteria. Greaves said: "Even if we confirmed both of these [findings], it is not evidence that we have found these magic microbes and they're living there today," adding that there were not yet "any ground truths." Dr Robert Massey, the deputy executive director at the Royal Astronomical Society, said in a statement: "These are very exciting findings but it must be stressed that the results are only preliminary and more work is needed to learn more about the presence of these two potential biomarkers in Venus's clouds. Nevertheless, it is fascinating to think that these detections could point to either possible signs of life or some unknown chemical processes. It will be interesting to see what further investigations unearth over the coming months and years."
In a second talk, Prof Jane Greaves, an astronomer at Cardiff University, presented preliminary observations from the Green Bank telescope indicating ammonia, which on Earth is made through either industrial processes or by nitrogen-converting bacteria. Greaves said: "Even if we confirmed both of these [findings], it is not evidence that we have found these magic microbes and they're living there today," adding that there were not yet "any ground truths." Dr Robert Massey, the deputy executive director at the Royal Astronomical Society, said in a statement: "These are very exciting findings but it must be stressed that the results are only preliminary and more work is needed to learn more about the presence of these two potential biomarkers in Venus's clouds. Nevertheless, it is fascinating to think that these detections could point to either possible signs of life or some unknown chemical processes. It will be interesting to see what further investigations unearth over the coming months and years."
Could be ... (Score:5, Insightful)
... but most probably not.
Unfortunately this kind of story is just irresistible clickbait fodder for science journalists. It was just as bad when phosphine was initially detected on Venus what, a couple of years ago? That finding was then refuted, as other studies looking at the same data couldn't detect it. If this detection actually stands and isn't refuted, then it will be very interesting, and warrant further study to find the source, but it's unlikely to be from living organisms, and I could really do without all the "signs of life" headlines until there's a bit more to go on.
Re:Could be ... (Score:5, Informative)
It's a lot more probable than you might want to admit, as even here, on earth, where the atmsphere is significantly less extreme, we have well-adapted microorganisms that live in it as their primary ecology.
https://www.ncbi.nlm.nih.gov/p... [nih.gov]
The paper mostly focuses on atmosphere as a transmigration pathway for microbial populations, but actually bona-fide atmospheric microbes exist here on earth.
A search for well adapted extremophiles on venus is not that unreasonable.
Assuming for granted they are there is unreasonable, but discounting them as "Unlikely!" without qualification, is just not sensible.
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It's a lot more probable than you might want to admit, as even here, on earth, where the atmsphere is significantly less extreme, we have well-adapted microorganisms that live in it as their primary ecology.
And it is not necessary that life began on Venus. Some particularly hardy microbes from Earth could have hitched a ride on ejectile from comet strikes.
Re:Could be ... (Score:5, Insightful)
1) Yes, microbes live in our atmosphere. It's not clear that they can actually *reproduce there*. At all, let alone faster than they're destroyed by UV, desiccation, etc.
2) Venus's atmosphere is intensely desiccating. It's so desiccating that even droplets of hydrochloric acid can't meaningfully exist in the "earthlike" middle cloud layer because the droplets of sulfuric acid want the water more and will desiccate the hydrochloric acid to HCl gas. A problem made worse by the fact that there's just not that much hydrogen to begin with - even the HCl droplets in the middle layer are sparse to the point that visibility is a couple kilometers. Venus lost almost all of its hydrogen. It's directly visible there in the isotopic signatures; it's 2H/1H ratio is over two orders of magnitude higher than Earth's. It's a planet with no intrinsic magnetic field receiving a much stronger solar wind flux than Earth. The outcome isn't hard to predict.
I like to speculate on - and am not super-pessimistic on - non-carbon-based life. But even I have trouble believing you're going to find life somewhere that microbes can't get ahold of hydrogen.
Venus is probably only second to Titan in our solar system for the complexity of its atmospheric chemistry, which is reminiscent of a chemical plant - a wide range of compounds are leached out of the rock by the hot hostile surface and transported up through radically different atmospheric layers where the chemical equilibria are radically altered en route. There's even friggin' *iron* in its atmosphere. Detecting somethig like phosgene shouldn't be at all surprising. It's not like they found RuBisCo in there or something; phosgene is a very simple molecule.
And the fact that we don't know what specific process is making it also shouldn't be at all surprising, because there's a ton we don't know about Venus, as Mars robs all the space exploration budget and other bodies like Venus just get the dregs (the US, which does the lion's share of global space spending, hasn't sent a dedicated mission to Venus since 1978). For example: calcs suggest there should be a lot of mercury in Venus's atmosphere (no shock there, it's obviously going to boil it out of cinnabar, right?). But we detect none, down to some pretty low detection limits. So where is it? Dunno, but unless you're speculating on some sort of "mercury-metabolizing life", you're not going to blame that one on life, are you?
Bit by bit we're deciphering things. For a long time it was unclear what the "mystery UV absorber" was in Venus's upper atmosphere, and there were lots of competing theories. But nowadays we're pretty sure that it's certain polysulfides (Venus has a very complex sulfur cycle), and have shown a reaction process that should produce them. But the process of decipherig the atmospheric chemistry is very difficult when it's so hard to get funding for probes to actually enter and descend through the atmosphere. The reaction you often get is "But we did study Venus!", and what they usually mean is, they launched a mission to Mars or the outer solar system, did one or more Venus flybys in the process, and from some long distance took pictures or maybe hit it with some radar during the brief time they were close. ESA and JAXA have sent (cheap) dedicated orbiters, but no probe has entered Venus's atmosphere to study it since Vega in 1984.
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** "Even HCl droplets in the middle layer -> "Even H2SO4 droplets in the middle layer"
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For a long time it was unclear what the "mystery UV absorber" was in Venus's upper atmosphere, and there were lots of competing theories. But nowadays we're pretty sure that it's certain polysulfides (Venus has a very complex sulfur cycle), and have shown a reaction process that should produce them.
Do you have a reference for this? Last I heard, there were numerous theories, but no consensus on the UV absorber identity.
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Odd, thought I replied to this earlier, but the reply doesn't seem to be here. Wrote that I hadn't seen anything in 5+ years that wasn't support for polysulfides, but that you're probably more current on the literature than I am. Then I went and did a search and found a paper from this year still arguing for iron compounds, so I retracted my statement )
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I won't claim to be up on the subject either. But thanks for checking.
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Pedantically, there was the Magellan mission launched in 1989. But your overall point still stands... https://en.wikipedia.org/wiki/Magellan_(spacecraft) [wikipedia.org]
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It's a lot more probable than you might want to admit, as even here, on earth, where the atmsphere is significantly less extreme, we have well-adapted microorganisms that live in it as their primary ecology.
https://www.ncbi.nlm.nih.gov/p... [nih.gov]= The paper mostly focuses on atmosphere as a transmigration pathway for microbial populations, but actually bona-fide atmospheric microbes exist here on earth.
Fascinating review article, thanks.
But the evidence for microbes actually reproducing in the atmosphere is somewhat weak. As you note, the article is mostly about microbes being transported in the atmosphere, not actually living there.
A search for well adapted extremophiles on venus is not that unreasonable. Assuming for granted they are there is unreasonable, but discounting them as "Unlikely!" without qualification, is just not sensible.
"Unlikely" is a good statement, but "unlikely" is not the same as "dismiss this out of hand."
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It's a lot more probable than you might want to admit, as even here, on earth, where the atmsphere is significantly less extreme, we have well-adapted microorganisms that live in it as their primary ecology.
Yes, but extremophiles here on Earth didn't likely evolve separately in their extreme conditions. If you have tons of areas that are incredibly suited for life, then life can start there and then very slowly evolve into extremophiles as its spreads into those environments.
If the extreme environment is all that you have, I don't see life starting there. Heck its hard enough to start life in general. To my knowledge we haven't even been able to create life from not-life in a lab yet. If we can't do that, t
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Yes, but extremophiles here on Earth didn't likely evolve separately in their extreme conditions. If you have tons of areas that are incredibly suited for life, then life can start there and then very slowly evolve into extremophiles as its spreads into those environments. If the extreme environment is all that you have, I don't see life starting there.
The current consensus on planetary evolution is that in the early solar system, when the sun was about 30% dimmer [sciencenews.org] than it is now, Venus had a temperate climate and an ocean. As the sun slowly got brighter, the wet greenhouse effect intensified and eventually the oceans boiled away. So, the hypothesis is that life started when the environment was benign, and then as it heated up, moved into the remaining ecological niche, the clouds.
Heck its hard enough to start life in general. To my knowledge we haven't even been able to create life from not-life in a lab yet.
Yes, the actual conditions for the origin of life is as yet unknown. We don'
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"We don't know how to do it" doesn't mean "the universe doesn't know how to do it."
We ARE the universe. Or at least the part of the universe that can think and experiment.
Evolution and abiogenesis is effectively operated by random chance. We can shape evolution very, very quickly. EG, we basically "created" the modern cow from the wild auroch (now extinct) via selective breeding, and the same with almost all modern dog breeds.
Basically placing specific intent behind trying to make something happen as opposed to waiting on it to randomly happen should speed it up. And if we can't make
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Utter speculation, with no more support than "this is my opinion."
The fact that we are part of the universe does not mean that we can do anything that the universe can do.
EG, we basically "created" the modern cow from the wild auroch (now extinct) via selective breeding, and the same with almost all modern dog breeds.
If you can breed a squid, starting with an amoeba, I'd say you have an argument. But you can't.
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If you can breed a squid, starting with an amoeba, I'd say you have an argument. But you can't.
I'd bet we could, eventually. And if nature took 500 million years to do randomly it I'd bet we could do it in 1 million years. The thing is, that's still a long time.
Unconvinced for Different Reasons (Score:5, Insightful)
It's a lot more probable than you might want to admit,
I'm still very unconvinced - not because it would be impossible for microbes to exist there but because the evidence is based on the fact that natural chemical processes cannot produce the gases detected. However, Venus is an exceptionally extreme environment with high temperatures and pressures plus a complex mix of chemicals and I'm not convinced that we know enough to be certain that these gases cannot be produced chemically in such an extreme, complex environment.
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Life on another planet could look very different to what we have on this planet. The way it is done here isn't necessarily the only way to do it.
Re: Could be ... (Score:1)
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Could be... but isn't. And, also, could not be.
Finally, It's Aliens!! (Score:2)
It's Aliens. No doubt. I can't wait to meet our rulers.
--
"It's Aliens" - Giorgio A. Tsoukalos
And when it's discovered to be sentient life (Score:1)
there is no life on venus (Score:2)
Re:there is no life on venus (Score:4, Insightful)
Extremophiles exist on earth and could potentially exist elsewhere. Anyway, we tend to think of planets of what they're like at the surface, but Venus has a very dense atmosphere and it has already been speculated that conditions higher up in the atmosphere could be amenable to life if it is inhospitable not further down. I expect scientists would love to launch a probe that floats around in the upper atmosphere to observe what is there.
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"Extremophiles exist on earth and could potentially exist elsewhere."
There seem to be a lot of them in Milwaukee at the moment.
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the conditions on venus is too harsh for life to exist, on a side note the elements for life (amino acids) is fairly common in the universe, it doesn't mean life is everywhere, but if a planet was in orbit around a stable sun in the goldilocks zone with the right environmental conditions life could get kickstarted
Because of the Goldilocks zone and our absolute dependence on it, I imagine we have a very narrow definition of what “life” might be in the greater picture. At a certain point in history we had no damn idea how fish survived underwater. We simply knew they did. We may be at that same point with understanding how life might survive in the universe too.
IIRC... (Score:4, Interesting)
James Lovelock's criteria for gasses indicating life required (a) that there be two unstable gasses, (b) that the gasses were in dynamic equilibrium, and (c) that the gasses react with each other.
His first argument was that life could only obtain energy from an unstable gas, since it takes energy to do much with a stable one, and that you needed a second form of life to complete the cycle, which must take in an unstable gas so the output from the first form of life must also be unstable.
His second argument was that an overoroduction of a food source would lead to an overoroduction in a consumer, and thus both sides of the system are going to be in dynamic equilibrium.
One can argue for days as to whether this applies to all life, but that's irrelevant in this argument, since the claim centres around two gasses.
It's been a while since I did the necessary chemistry, so I'll rely on the other nerds here.
Do these two gasses meet James Lovelock's three criteria?
If no, then the lack of knowledge of a chemical process is immaterial. There will be one, and it almost certainly isn't living.
If yes, then it gets more interesting. Then we really do have to consider the possibility of life. It still seems very improbable, but we would have a definite test of Lovelock's model. This is important as it's the only model that claims to definitely detect life remotely. If it is a sound model, we can apply it to exoplanets, where remote detection is all we can do.
High temperature proteins? (Score:2)
How is that supposed to work. Extremophiles have adapted proteins that do not unfold easily so they can remain active in temperatures up to 120C. In hundreds of degrees Celsius however I wouldn't even start looking.
I don't take serious treating phosphine as indicating signs of life . It's just taking a very speculative claim and trying to make news with it.
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How is that supposed to work. Extremophiles have adapted proteins that do not unfold easily so they can remain active in temperatures up to 120C. In hundreds of degrees Celsius however I wouldn't even start looking.
The hypothesis is that microorganisms could live in the cloud layer, where temperatures are in the liquid water range (between 0 and 100 C), not at the surface.
https://ntrs.nasa.gov/api/cita... [nasa.gov]
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Thanks. I still don't see it though. It's not like a life form would stay up there at the same altitude. You could imagine something like "it just pauses when it drops and resumes when regaining altitude" but together with it being in a gas and corrosive I think the claim could be phrased as "it's not totally impossible".
I'd like to see a probe bring a (Score:2)
...sample back to Earth, but there is a non-zero risk that we could inadvertently unleash a pathogen that Earth life has insufficient immunity to, creating a giant mess.
And yes, I do realize it is highly unlikely, but is a risk of say 0.0001% still worth the gamble?
I'd rather see a manned in-orbit or moon lab do the sample testing to limit exposure to unfortunate astronauts.
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...sample back to Earth, but there is a non-zero risk that we could inadvertently unleash a pathogen that Earth life has insufficient immunity to, creating a giant mess.
Anything that could live in the clouds of Venus would have to be a hyper-acidophile. Really no chance it could survive anywhere on Earth; even acid mine drainage isn't anywhere even close to the pH of Venus clouds.
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> would have to be a hyper-acidophile
It may end up thriving in mammal stomachs.
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> would have to be a hyper-acidophile
It may end up thriving in mammal stomachs.
Not even close to the acid content of Venus clouds.
Venus farts? (Score:2)
Of course there is life! (Score:1)