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From a co-author of the paper: > This means either this is life, or it’s some sort of physical or chemical process that we do not expect to happen on rocky pla

by nprz 6y ago

From a co-author of the paper: > This means either this is life, or it’s some sort of physical or chemical process that we do not expect to happen on rocky planets. We really went through all possible pathways that could produce phosphine on a rocky planet. If this is not life, then our understanding of rocky planets is severely lacking. https://webcache.googleusercontent.com/search?q=cache:dUWrpm80WHsJ:https://earthsky.org/%3Fp%3D343883+&cd=1&hl=en&ct=clnk&gl=us https://webcache.googleusercontent.com/search?q=cache:dUWrpm...

ericmay 6y ago
What’s great here is that this means it’s potentially a profound and important scientific observation either way! Obviously one is a bit more profound than the other, but nevertheless.
monkeydreams 6y ago
> If this is not life, then our understanding of rocky planets is severely lacking. While I would love for this to be true, ignorance requires fewer assumptions than life at any level of complexity.
- gfodor 6y ago
  Why would it be surprising to find bacteria next door? If life is common in the universe, this would be exactly what you’d expect. And there is plenty of reason to think life is common in the universe.
  - monkeydreams 6y ago
    > Why would it be surprising to find bacteria next door? No one said it would be surprising (though it would to a great many people), the point is that it would require a LOT of assumptions about how life develops to get us to that point whereas human ignorance is the sole assumption we need to make to assume that these measurements are not life-related. I think life is everywhere in the universe and that we will find that it descends along a great many entropic pathways in a great many frames of reference. But I also believe any given hint of life is more likely than not going to be related to human error, only because we have so many assumptions we need to make until we understand the underlying processes better.
- glenstein 6y ago
  Right. This just reminds me of the news cycle from 2011 or so about a paper reporting neutrinos moving at faster-than-light speed. Which turned out to be a false alarm. https://www.nationalgeographic.com/news/2011/9/110923-neutrinos-speed-of-light-particles-cern-physics-einstein-science/ https://www.nationalgeographic.com/news/2011/9/110923-neutri...
edjrage 6y ago
Ok, potentially stupid question, but isn't "life" just such a "pathway"? Meaning an organism already assumes a complex system of chemical reactions, and then some other chain to produce phosphine? So is it really hard to believe that if "our understanding of rocky planets" already assumes something as complex as life is possible, then something less complex than life (but still possibly quite complex) which produces phosphine is also possible?
- kittiepryde 6y ago
  Yes, "life" is a "pathway". The link for the paper didn't work for me, but I'm thinking the issue here is the "pathway" with "life" involved is now the simplest system that can produce the observed results. From the Quora article: "The volume of Phosphine observed was stunning. They ruled out minerals blown into the atmosphere, volcanism, lightning and other known sources as there is simply no process that could maintain this abundance. So much Phosphine was observed we could conclude that the atmosphere of Venus is “teeming with life”."
  - jerf 6y ago
    One wonders if that isn't proving too much; if the atmosphere of Venus is "teeming with life" one would not expect the only such signature to be an excess of phosphine only noticed after centuries of observation. I mean, I realize not all life necessarily engages in photosynthesis that emits highly reactive O2 into their atmosphere and radically and highly visibly transforms the entire atmosphere, but since the only energy source on the geological time frames those bacteria are going to be able to count on in the high atmosphere is going to be sunlight one would rather expect "teeming with life" to have very obvious spectra effects, i.e., "turning the planet funny colors" as life uses light energy in some sort of photosynthesis-like reaction, not merely creating an unexpected abundance of phosphine. "Life scraping by" is a lot easier to believe than "teeming with life". "Teeming" life has no compelling evolutionary reason to also be well-hidden from us, and a lot of pathways to being very obvious as it exploits the energy available.
    - TeMPOraL 6y ago
glenstein 6y ago
Thanks, but I was familiar with that conclusion already and that's not quite what I'm asking for. What I'm asking is some ballpark idea of the relative plausibility of (1) microbes, compared to (2) having discovered some new physical/chemical processes. Is it a case where we feel like we've got our understanding of (2) locked down, and so "it would have to be a chemical process we've never seen" is a way of saying it's highly likely to be life? Or is it very plausible that we do have much more to learn about chemical processes, and it's just a face value statement? Are we talking 99% life, 1% likelihood of new process? 50/50? Something else?
rorykoehler 6y ago
From my layman perspective it sounds like this is a groundbreaking discovery regardless.

by nprz 6y ago

ericmay 6y ago

What’s great here is that this means it’s potentially a profound and important scientific observation either way! Obviously one is a bit more profound than the other, but nevertheless.

monkeydreams 6y ago

> If this is not life, then our understanding of rocky planets is severely lacking. While I would love for this to be true, ignorance requires fewer assumptions than life at any level of complexity.

gfodor 6y ago
Why would it be surprising to find bacteria next door? If life is common in the universe, this would be exactly what you’d expect. And there is plenty of reason to think life is common in the universe.
- monkeydreams 6y ago
  > Why would it be surprising to find bacteria next door? No one said it would be surprising (though it would to a great many people), the point is that it would require a LOT of assumptions about how life develops to get us to that point whereas human ignorance is the sole assumption we need to make to assume that these measurements are not life-related. I think life is everywhere in the universe and that we will find that it descends along a great many entropic pathways in a great many frames of reference. But I also believe any given hint of life is more likely than not going to be related to human error, only because we have so many assumptions we need to make until we understand the underlying processes better.
glenstein 6y ago
Right. This just reminds me of the news cycle from 2011 or so about a paper reporting neutrinos moving at faster-than-light speed. Which turned out to be a false alarm. https://www.nationalgeographic.com/news/2011/9/110923-neutrinos-speed-of-light-particles-cern-physics-einstein-science/ https://www.nationalgeographic.com/news/2011/9/110923-neutri...

edjrage 6y ago

Ok, potentially stupid question, but isn't "life" just such a "pathway"? Meaning an organism already assumes a complex system of chemical reactions, and then some other chain to produce phosphine? So is it really hard to believe that if "our understanding of rocky planets" already assumes something as complex as life is possible, then something less complex than life (but still possibly quite complex) which produces phosphine is also possible?

kittiepryde 6y ago
Yes, "life" is a "pathway". The link for the paper didn't work for me, but I'm thinking the issue here is the "pathway" with "life" involved is now the simplest system that can produce the observed results. From the Quora article: "The volume of Phosphine observed was stunning. They ruled out minerals blown into the atmosphere, volcanism, lightning and other known sources as there is simply no process that could maintain this abundance. So much Phosphine was observed we could conclude that the atmosphere of Venus is “teeming with life”."
- jerf 6y ago
  One wonders if that isn't proving too much; if the atmosphere of Venus is "teeming with life" one would not expect the only such signature to be an excess of phosphine only noticed after centuries of observation. I mean, I realize not all life necessarily engages in photosynthesis that emits highly reactive O2 into their atmosphere and radically and highly visibly transforms the entire atmosphere, but since the only energy source on the geological time frames those bacteria are going to be able to count on in the high atmosphere is going to be sunlight one would rather expect "teeming with life" to have very obvious spectra effects, i.e., "turning the planet funny colors" as life uses light energy in some sort of photosynthesis-like reaction, not merely creating an unexpected abundance of phosphine. "Life scraping by" is a lot easier to believe than "teeming with life". "Teeming" life has no compelling evolutionary reason to also be well-hidden from us, and a lot of pathways to being very obvious as it exploits the energy available.
  - TeMPOraL 6y ago

glenstein 6y ago

Thanks, but I was familiar with that conclusion already and that's not quite what I'm asking for. What I'm asking is some ballpark idea of the relative plausibility of (1) microbes, compared to (2) having discovered some new physical/chemical processes. Is it a case where we feel like we've got our understanding of (2) locked down, and so "it would have to be a chemical process we've never seen" is a way of saying it's highly likely to be life? Or is it very plausible that we do have much more to learn about chemical processes, and it's just a face value statement? Are we talking 99% life, 1% likelihood of new process? 50/50? Something else?

rorykoehler 6y ago

From my layman perspective it sounds like this is a groundbreaking discovery regardless.