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Life on Venus?


Gargamel

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7 hours ago, Dragon01 said:

Venus has 3.5% of nitrogen in the atmosphere, so that wouldn't be a problem (aside from the fact nitrogen fixation is an energy hog).

Well, we are talking about a pressure around 1atm, so 3.5% there compared to 78% here... Dunno if that's low enough to be a problem, but yes, it would be an energy hog, lots of things for such life would be energy hogs, including producing phosphene.

Its growth could be energy limited, despite the sunlight.

 

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To be fair, life routinely does things which are energetically unfavorable, such as splitting CO2. :) In fact, that's what got people thinking about life in first place. Also, it's obviously limited by something, if it wasn't we would've seen far more obvious signs than a little excess phosphine. Might be by available energy. As for N2, remember, CO2 is 0.04% in Earth's atmosphere, and plants generally need more carbon than they do nitrogen. 3.5% should be fine.

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10 hours ago, Dragon01 said:

To be fair, life routinely does things which are energetically unfavorable, such as splitting CO2. :) In fact, that's what got people thinking about life in first place.

Well my point is that there may be an energy limitation similar to the very slow growing microbes that I included a link about.

If any life on Venus needs to do a lot of energy intensive reactions, despite the ample sunlight, it may end up with an energy limitation.

Anyway, I consider this chemical finding to be less interesting than this other 10 year old chemical finding: https://www.jpl.nasa.gov/news/news.php?release=2010-190

Its interesting and deserves further investigation, but I would still bet against life.

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Well, based on my knowledge of biology, I would hedge my bets. :) Titan is a bit harder problem, because we've known for a long time that it's very interesting and fully deserving of further, detailed study, but it's too bloody far away for that. Same with Europa. If it wasn't for the fact it's orbiting Jupiter, we'd be all over it already. Titan is even worse in that regard, that's the reason only one landing was ever attempted. The coolest historical proposals for exploring those generally launched on a Saturn V or N1 (a few on Energia or UR-700). Venus and Mars are much easier to get to, which is part of why this is getting so much attention.

Also, "energy limitation" doesn't automatically mean they'd be that slow. In fact, Venus is quite close to the Sun, which means more available sunlight, even if we account for clouds filtering it (and not all radiation is subject to this). That before we even consider chemosynthesis. Yes, they may be energy-limited to some degree, but I'd rather expect biochemistry to limit the reproduction rate. Remember, there are organisms on Earth that also have a lot of energy-heavy biochemistry, and they reproduce at a sensible pace, unless they live in an extremely energy-starved environment. 

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Pfft. I would bet an arm and a leg it isn't life. Maybe there are underground phosphine wells on Venus, and they leak, or something.

All the same, more motivation for a modern Venus mission.

Edited by SOXBLOX
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1 hour ago, kerbiloid said:

https://translate.google.com/translate?hl=ru&sl=ru&tl=en&u=https://trv-science.ru/2020/09/22/phosphine-na-venere/

Briefly: most probably, the basalts contain a lot of phosphides, and scattered pools of condensed sulfic acid react with it here and there.

Interesting. Here is a relevant quote from this paper (https://arxiv.org/abs/2009.06499)

 

The measurements suggest that the Venus’ crustal composition is extremely similar to terrestrial tholeitic basalts. Terrestrial basalts contain very low amounts of phosphorus (0.08% - 0.45%). If phosphorus is present on the surface of Venus, it is likely to be in the form of phosphate salts. We have considered phosphate salts of Mg, Ca, Al and K, with fluorapatite included as well as HF is probably present in the atmosphere. Phosphate minerals were assumed to be present as differentiated minerals, i.e. as pure solids whose activity is 1. The presence of pure solids is geologically unlikely, but (as with many other assumptions in this paper) presents a ‘best case scenario’ for making phosphine chemically.

 

This independent paper seems to agree that the phosphorus concentrations of basalts is low, at least on Earth (https://link.springer.com/article/10.1007/s11104-012-1490-2)

Edited by korwynkim
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Here is a detailed interview with one of the authors about the possibility of life on Venus: https://youtu.be/vnLqUiaWXnA

 

A few of the topics covered:

  • Correlation of phosphine with the unknown UV absorbers
  • Implausibility of contamination from Soviet probes
  • It would have to be "life as we don't know it" even if it uses water based biochemistry or has DNA
  • Possibility of silicon based life using sulfuric acid as a solvent
  • Photosynthesis isn't limited to fixing carbon
  • Whether oxygen is required for complex multicellular life
  • Whether we could tell if life on Venus and Earth shares the same origin

Also, going through past data from the ExoMars TGO orbiter suggests there is little to no phosphine on Mars: https://orbiterchspacenews.blogspot.com/2020/09/russian-spectrometer-did-not-detect.html

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14 minutes ago, kerbiloid said:

So many speculations from so few facts instead of just "we should locate the source of phosphine" looks like someone is trying to make a funding save throw.

https://www.google.com/search?q=5d10&oq=5d10&aqs=chrome..69i57j0l7.1638j0j1&sourceid=chrome&ie=UTF-8

Rolled a 25, what does that get me from NASA?

Also, AHEM, funding check

We have nerds of the other kind here, too.

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What about a chemo-synthetic organism that uses the hilarious amounts of UV to assist in breaking down the Sulfuric Acid? That's what I'd be thinking of if i thought it was life; especially since there's similar extremophiles on earth.

Mind you i think it's actually that we don't know the geology/atmosphere of Venus as well as we'd like to think and some non-biotic process is responsible. But the idea that it's some Silicon-Based organism or even more far-fetched ideas (There's a vocal minority that REALLY wants it to be a ancient, intelligent civilization that polluted itself to extinction....despite how absolutely absurd that is (The complex life developing; not the pollution).) i think is pretty much a distraction.

If it's something weird that's fantastic! But it's more than likely way, way closer to something we find near geysers here or around hydrothermal vents if it is life at all, and i think people get way too caught up in that prospect. Venus's Atmosphere hasn't been well sounded, and the surface has only been really touched by a few probes and RADAR scans. There's likely so much geology we just don't know about because of how hostile the planet is, and how little attention it's gotten.

So i guess the bottom line to me is, that no matter what we should probably give Venus a few missions.  Because if nothing else; this has revealed a big blindspot in our backyard that we'd likely benefit from making a little clearer.

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8 hours ago, korwynkim said:

Here is a detailed interview with one of the authors about the possibility of life on Venus: https://youtu.be/vnLqUiaWXnA

 

A few of the topics covered:

  • Correlation of phosphine with the unknown UV absorbers
  • Implausibility of contamination from Soviet probes
  • It would have to be "life as we don't know it" even if it uses water based biochemistry or has DNA
  • Possibility of silicon based life using sulfuric acid as a solvent
  • Photosynthesis isn't limited to fixing carbon
  • Whether oxygen is required for complex multicellular life
  • Whether we could tell if life on Venus and Earth shares the same origin

Also, going through past data from the ExoMars TGO orbiter suggests there is little to no phosphine on Mars: https://orbiterchspacenews.blogspot.com/2020/09/russian-spectrometer-did-not-detect.html

The segment on panspermia is very interesting, especially the idea that life on Earth came from Venus. The origin of life on Earth has always dumbfounded scientists, as simple life appears to just have appeared suddenly in the fossil record with little evidence of precursor forms, if I remember correctly. Earth life coming from Venus seems to be a perfect explanation for this problem.

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1 hour ago, coyotesfrontier said:

The segment on panspermia is very interesting, especially the idea that life on Earth came from Venus. The origin of life on Earth has always dumbfounded scientists, as simple life appears to just have appeared suddenly in the fossil record with little evidence of precursor forms, if I remember correctly. Earth life coming from Venus seems to be a perfect explanation for this problem.

Except it really isn't; it just shifts the elusive common ancestor somewhere else. And i would heavily doubt whatever microbe might be floating in the clouds now would be too closely related either.

Plus, Mars and Venus were both reasonably habitable at this point in time. Why would it just be a two-way exchange? It could've very well been a three-way exchange, with multiple stages of material being ejected from each to the other and back over millions of years. At which point that brings in another set of issues.

Don't get me wrong; i really like the idea of "Panspermia". But until we get a decent presence on all 3 bodies i think it's going to continue to be elusive at best to prove. Doubly so on Venus, because unless something miraculous happened somewhere on Venus there's going to be no fossil evidence of anything except cataclysmic volcanic eruptions. Let alone microbes...best we might be able to do is find a primitive martian organism and whatever might be in Venus's atmosphere and sequence both...assuming either exist in the first place. 

Oh and then there's the really, really fun option #3

Life, simple microbial life developed independently on all 3 planets, and never crossed over. At which point; we'd now have to ask how. And also has the rather dire implication for the Fermi paradox that life is so common that it will spool up wherever it can, and we're surrounded by potentially habitable worlds.....many which have a 100+ year head start.

Mind you; this is just me really saying in way too many words "We need to stop messing around and get out there" again :P

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Well - in case life began independently on all three planets (+ Europa, Enceladus and whatnot) it should really help the biology to finally partially figure out the process of abiogenesis. Three (or more) data points are better than one.

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11 hours ago, kerbiloid said:

So many speculations from so few facts instead of just "we should locate the source of phosphine" looks like someone is trying to make a funding save throw.

In general, I think speculation is helpful or even necessary for generating hypotheses. In the case of this interview, the whole point was to discuss and speculate about the possibility and nature of life on Venus. Nobody is denying that we should locate the source of phosphine.

As for the origin of life, many complex organic molecules like amino acids and other building blocks of RNA/DNA have been found in comets, meteorites, the interstellar medium, and even a protostar. The gap between these molecules and microbes is still a big mystery, but at the very least, it seems like the ingredients for life as we know it are abundant or easily formed.

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3 minutes ago, korwynkim said:

many complex organic molecules like amino acids and other building blocks of RNA/DNA have been found in comets, meteorites, the interstellar medium, and even a protostar

For me it means not "the life is everywhere", but "the life needs a lot of things beyond just presence of typical compounds".

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4 minutes ago, kerbiloid said:

For me it means not "the life is everywhere", but "the life needs a lot of things beyond just presence of typical compounds".

I never said it meant that life is everywhere. It gives us a starting point. Whether or not life needs things beyond just the presence of building blocks to start is the Big Question, isn't it? On one hand, life on Earth started almost as soon as it was able. On the other hand, we have no evidence of the steps leading up to the first microbe, and we don't know how it would have happened.

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6 minutes ago, korwynkim said:

I never said it meant that life is everywhere. It gives us a starting point. Whether or not life needs things beyond just the presence of building blocks to start is the Big Question, isn't it? On one hand, life on Earth started almost as soon as it was able. On the other hand, we have no evidence of the steps leading up to the first microbe, and we don't know how it would have happened.

We have at least one thing differing from other places in Solar System. The Moon.

Its arrival has forced the geological evolution of the Earth dramatically, so unlike the Venus with its tesseras, we have a full-featured system of continental platforms and the core which had been extracted quickly and became a magneto of our bike, in both geological and magnetospherical senses of the word.

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On 9/25/2020 at 2:13 AM, coyotesfrontier said:

The origin of life on Earth has always dumbfounded scientists, as simple life appears to just have appeared suddenly in the fossil record with little evidence of precursor forms, if I remember correctly. Earth life coming from Venus seems to be a perfect explanation for this problem.

Except it ain't. "Early Earth" was inhospitable enough, don't you think? Why try to explain life by saying it came from somewhere even less likely to support stable chemistry than Earth?

I think its much more likely that aliens came and burned away the fossil records, creating the inconsistencies we see today. :D

Spoiler

Joking.

 

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On 9/25/2020 at 3:13 AM, coyotesfrontier said:

simple life appears to just have appeared suddenly in the fossil record with little evidence of precursor forms

I'm just busting your balls, but its not like there were fossils found that were non-life in origin. If life happened, it would be expected that they "appeared suddenly." Its life! It suddenly dominates everywhere that is conducive to life...at least where we can observe life exists. I am not going to bet on a bunch of rocks to kill off microbes.

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It's not life that "suddenly appeared", but the fossils. That is, the only thing that happened "suddenly" was life becoming complex enough to leave a fossil record. Before it, there could be any number of forms that did not, it takes a reasonably complex organism to leave anything recognizable behind. The very basic life forms could have been around for a very long time, and we wouldn't know, because they simply did not have any parts that would leave a lasting mark on the rocks.

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My guess is that there were pools of water with enough chemistry shenanigans going on inside, catalyzed by volcanic heat and solar energy and lightning, that the whole puddle acted sort of like a cell, strung up some RNA, and eventually mutated into something with membranes organizing things. It's reasonable to assume this happened on Earth, but as long as Venus or Mars had similar environments at the time I don't see why life shouldn't have sprung up on all three.

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