6 ms·

Titan is actually high on my list of places that could harbor life. I’m not talking about subsurface water though that’s possible. I mean chemically alien life

by api 2y ago

Titan is actually high on my list of places that could harbor life. I’m not talking about subsurface water though that’s possible. I mean chemically alien life. The reason I suspect this is a phenomenon understood in theory of complexity and evolutionary informatics circles called the “edge of chaos.” Oversimplifying a bit you get universal computation in the vicinity of a phase boundary. Titan is loaded with phase boundaries: solid, liquid, gas, dynamic changes between them, rain, dissolving and crystallizing solids, etc. The solvent is just light hydrocarbons not water. Life on Titan would be slow and low metabolism compared to us (probably). We should be aware of this likely difference when looking. What looks like minerals, rocks, weird films of chemicals, etc may be alive. We should look for structure, metabolism, isomer preferences, etc. Of course life on Titan is convinced there could never be life here. The third planet is a literal hell where it rains molten dihydrogen monoxide in an atmosphere of corrosive oxygen. Any life there would vaporize and oxidize instantly. Rumors of a strange disc shaped object being recovered with material and isotope ratios pointing to the third planet are entirely unfounded, as are rumors of amateur radio enthusiasts picking up signals from there.

abhijat 2y ago
At least we share concepts of hell and amateur radio.
pfdietz 2y ago
> Life on Titan would be slow and low metabolism compared to us (probably). On the other hand, maybe the chemistry there could be using less stable chemicals where less energy is needed to change them. It's at a much lower temperature, after all. I suspect we'll find nothing, though, due to Fermi. If two different Origin of Life events happen in the same system, OoL (of at least one of those kinds) must be common in the universe, and that would remove what I consider the big potential obstacle to abundant intelligence in the universe. Just an intuition without more data, of course.
- kaibee 2y ago
  Its wholly possible for the universe to be teeming with single-celled life, but I think the jump to multicellular, intelligent, civilization, and space-faring (at least signals wise) could still cut it to a factor 1/1000 stars. And we're relatively early in the life of the universe still.
  - pfdietz 2y ago
    Cutting it to 1/1000 stars wouldn't be anywhere near enough to get around Fermi, by many orders of magnitude.
  - JumpCrisscross 2y ago
    > could still cut it to a factor 1/1000 stars I’m a multicellular rare Earther. We’ve had on the order of 10^40 cells, ever [1]. Symbiogenesis occurred, from what we can tell, once [2]. (For comparison, there are 10^11 stars in the Milky Way [3] and 10^24 in the observable universe [4].) We might be able to argue that factor should be cut, since any late symbiogeneses would be outcompeted into oblivion. But that still, optimistically, puts us in the realm of the Milky Way’s star count. [1] https://www.cell.com/current-biology/abstract/S0960-9822(23)01286-1 https://www.cell.com/current-biology/abstract/S0960-9822(23)... [2] https://en.m.wikipedia.org/wiki/Symbiogenesis https://en.m.wikipedia.org/wiki/Symbiogenesis [3] https://en.m.wikipedia.org/wiki/Milky_Way https://en.m.wikipedia.org/wiki/Milky_Way [4] https://en.m.wikipedia.org/wiki/Observable_universe#Matter_and_mass https://en.m.wikipedia.org/wiki/Observable_universe#Matter_a...
    - api 2y ago
      The basic idea of rare Earth as an answer to Fermi is that if the frequency of advanced life is around 1 per galaxy per billion years or something like that then we'd likely never meet any aliens. Intergalactic travel is borderline impossible barring unknown physics or travel very close to the speed of light. Even at speeds like 0.5c (50% the speed of light) the trip would take so long you'd have problems like cosmic rays tearing you apart over such long spans of time, and in the vastness of intergalactic space there's no place to pitch a tent and chill and repair things. 0.5c would get you to the stars but not the galaxies. Intergalactic flight would require something more like 0.95c to 0.99c. The energy requirements for that are insane and possibly unachievable, and if you hit a dust particle at that speed the yield will be like a thermonuclear bomb. The cosmic microwave background also becomes a beam of hard gamma rays aimed at your head. All kinds of crazy extreme physics things happen. Lastly, why do it? Galaxies are huge and if you're alone then it's all yours. The only conceivable reason would be to flee some galactic-scale super-catastrophe like your galaxy's central black hole behaving badly and frying everything with gamma rays. Even for that it might be easier to burrow deeply into planetary bodies instead. Of course one can imagine ultra-far-future scenarios like: what if Andromeda hosts some galactic-scale super civilization by the time it hits the Milky Way which by then also hosts such a thing. That'd be a hoot.
- mtlmtlmtlmtl 2y ago
  I'm highly sceptical of the Fermi paradox being a meaningful paradox at all. I don't think we have nearly enough data to make any conclusion at all about the frequency of intelligent life in our own galaxy, let alone the universe. We've only started finding exoplanets in the last few decades, and the frequency of exoplanet detection was very low for most of that time and is still growing today. The ability to learn much of anything about the environments of these planets is even more recent, just a few years since the launch of JWST, and still very limited. It's still only "reliable" for fairly large planets, mostly gas giants. And even for those planets our ability to model the data is an area of active, painstaking research. The number of planets whose atmospheres we have any data-backed information about is very very low. So it seems like the only real argument for the Fermi paradox(certainly back in the 50s when Fermi proposed it) is that we haven't been visited or received any communication. But even that's worthy of doubt. Indeed, our ability to detect and characterise very small objects in or passing through the solar system is fairly limited even today, and was practically non-existent before. It seems very plausible that alien probes could have visited our solar system many times without us noticing. It could for instance be the case that this is only possible by way of technologies that can't easily decelerate and so they've only passed through. We'd have to be pretty lucky to spot something like that, at the size it would likely be, passing through only for a short time(given the speed it would have to move at). As for radio signals, the amount of funding that goes into projects like SETI is not exactly earth-shattering and also hasn't been going on for very long. It's a pretty fringe area of research. The amount of interference from earth-based radio sources also makes this research quite difficult. I'm not some UFO nut, btw. I'm not arguing for conspiracy theories involving the US government, alien abductions, yadda yadda. I'm just asking what do we really know? Not very much, it seems to me.
  - api 2y ago
    Obligatory XKCD: https://xkcd.com/638/ https://xkcd.com/638/ I completely agree. We haven't been looking very long and very hard and we're not even that sure what to look for or where to look. All we can say right now is that we do not see any unambiguous signs of ETI, but space is called space for a reason. We are also searching the vastness of time. I don't completely dismiss ET-origin UFOs. I don't think there's anywhere near enough evidence to make such a claim as anything more than a hypothesis, but remember that one possible answer to the Fermi paradox is that there isn't one.
- exochrono 2y ago
  obligatory reference to the dark forest hypothesis (https://en.wikipedia.org/wiki/Dark_forest_hypothesis https://en.wikipedia.org/wiki/Dark_forest_hypothesis) as an alternate explanation for the apparent rarity of life
Galatians4_16 2y ago
> light hydrocarbons Sounds like Titan needs Democracy.
tshaddox 2y ago
> Of course life on Titan is convinced there could never be life here. The third planet is a literal hell where it rains molten dihydrogen monoxide in an atmosphere of corrosive oxygen. Any life there would vaporize and oxidize instantly. What are some of the chemicals that would vaporize and oxidize instantly in Earth’s atmosphere which this hypothetical Titan life could be made of?
- dexwiz 2y ago
  Almost any light hydrocarbon (4 carbons or smaller) vaporizes in the Earths atmosphere. Oxygen is pretty corrosive and we have all sorts of biological systems to slow or prevent this.
- gus_massa 2y ago
  > Any life there would vaporize and oxidize instantly. I don't expect a fast oxydation that set them in flames, but I expect them to fell what you would feel if you take a bath in bleach. To get a nice fire instantly on Earth, you need something like the substances in https://en.wikipedia.org/wiki/Autoignition_temperature https://en.wikipedia.org/wiki/Autoignition_temperature . The ones with low temperature are Triethylborane −20 °C (−4 °F): It looks like something that you could find in Titan, but I don't remember reading about that. The structure is not so weird, and there are some similar molecules with nitrogen instead of boron. I don't remember massive natural production of organic molecules with boron, but boron chemistry is very weird and well above my chemistry level. Silane 21 °C (70 °F): It would be more strange to have too many organic molecules with silicon. Phosphorus (white) 34 °C (93 °F): I don't think it's stable enough to be acumulated naturay. It's too energetic and I expect it to react with some of the molecules in Titan.
buu700 2y ago
I'm not sure if this is what you meant, but the concept of an alien species with a totally different subjective perception of time would be interesting. As in all of our actions/movements/speech would be experienced as being on e.g. 10x fast forward to them, or vice versa.
- 0cf8612b2e1e 2y ago
  Dragon’s Egg is a story about this concept. Spoilers from the Wikipedia The rest of the story, including almost the whole history of cheela civilization, spans from 22 May 2050 to 21 June 2050. By humans' standards, a "day" on Dragon's Egg is about 0.2 seconds, and a typical cheela's lifetime is about 40 minutes.

by api 2y ago

abhijat 2y ago

At least we share concepts of hell and amateur radio.

pfdietz 2y ago

> Life on Titan would be slow and low metabolism compared to us (probably). On the other hand, maybe the chemistry there could be using less stable chemicals where less energy is needed to change them. It's at a much lower temperature, after all. I suspect we'll find nothing, though, due to Fermi. If two different Origin of Life events happen in the same system, OoL (of at least one of those kinds) must be common in the universe, and that would remove what I consider the big potential obstacle to abundant intelligence in the universe. Just an intuition without more data, of course.

kaibee 2y ago
Its wholly possible for the universe to be teeming with single-celled life, but I think the jump to multicellular, intelligent, civilization, and space-faring (at least signals wise) could still cut it to a factor 1/1000 stars. And we're relatively early in the life of the universe still.
- pfdietz 2y ago
  Cutting it to 1/1000 stars wouldn't be anywhere near enough to get around Fermi, by many orders of magnitude.
- JumpCrisscross 2y ago
  > could still cut it to a factor 1/1000 stars I’m a multicellular rare Earther. We’ve had on the order of 10^40 cells, ever [1]. Symbiogenesis occurred, from what we can tell, once [2]. (For comparison, there are 10^11 stars in the Milky Way [3] and 10^24 in the observable universe [4].) We might be able to argue that factor should be cut, since any late symbiogeneses would be outcompeted into oblivion. But that still, optimistically, puts us in the realm of the Milky Way’s star count. [1] https://www.cell.com/current-biology/abstract/S0960-9822(23)01286-1 https://www.cell.com/current-biology/abstract/S0960-9822(23)... [2] https://en.m.wikipedia.org/wiki/Symbiogenesis https://en.m.wikipedia.org/wiki/Symbiogenesis [3] https://en.m.wikipedia.org/wiki/Milky_Way https://en.m.wikipedia.org/wiki/Milky_Way [4] https://en.m.wikipedia.org/wiki/Observable_universe#Matter_and_mass https://en.m.wikipedia.org/wiki/Observable_universe#Matter_a...
  - api 2y ago
    The basic idea of rare Earth as an answer to Fermi is that if the frequency of advanced life is around 1 per galaxy per billion years or something like that then we'd likely never meet any aliens. Intergalactic travel is borderline impossible barring unknown physics or travel very close to the speed of light. Even at speeds like 0.5c (50% the speed of light) the trip would take so long you'd have problems like cosmic rays tearing you apart over such long spans of time, and in the vastness of intergalactic space there's no place to pitch a tent and chill and repair things. 0.5c would get you to the stars but not the galaxies. Intergalactic flight would require something more like 0.95c to 0.99c. The energy requirements for that are insane and possibly unachievable, and if you hit a dust particle at that speed the yield will be like a thermonuclear bomb. The cosmic microwave background also becomes a beam of hard gamma rays aimed at your head. All kinds of crazy extreme physics things happen. Lastly, why do it? Galaxies are huge and if you're alone then it's all yours. The only conceivable reason would be to flee some galactic-scale super-catastrophe like your galaxy's central black hole behaving badly and frying everything with gamma rays. Even for that it might be easier to burrow deeply into planetary bodies instead. Of course one can imagine ultra-far-future scenarios like: what if Andromeda hosts some galactic-scale super civilization by the time it hits the Milky Way which by then also hosts such a thing. That'd be a hoot.
mtlmtlmtlmtl 2y ago
I'm highly sceptical of the Fermi paradox being a meaningful paradox at all. I don't think we have nearly enough data to make any conclusion at all about the frequency of intelligent life in our own galaxy, let alone the universe. We've only started finding exoplanets in the last few decades, and the frequency of exoplanet detection was very low for most of that time and is still growing today. The ability to learn much of anything about the environments of these planets is even more recent, just a few years since the launch of JWST, and still very limited. It's still only "reliable" for fairly large planets, mostly gas giants. And even for those planets our ability to model the data is an area of active, painstaking research. The number of planets whose atmospheres we have any data-backed information about is very very low. So it seems like the only real argument for the Fermi paradox(certainly back in the 50s when Fermi proposed it) is that we haven't been visited or received any communication. But even that's worthy of doubt. Indeed, our ability to detect and characterise very small objects in or passing through the solar system is fairly limited even today, and was practically non-existent before. It seems very plausible that alien probes could have visited our solar system many times without us noticing. It could for instance be the case that this is only possible by way of technologies that can't easily decelerate and so they've only passed through. We'd have to be pretty lucky to spot something like that, at the size it would likely be, passing through only for a short time(given the speed it would have to move at). As for radio signals, the amount of funding that goes into projects like SETI is not exactly earth-shattering and also hasn't been going on for very long. It's a pretty fringe area of research. The amount of interference from earth-based radio sources also makes this research quite difficult. I'm not some UFO nut, btw. I'm not arguing for conspiracy theories involving the US government, alien abductions, yadda yadda. I'm just asking what do we really know? Not very much, it seems to me.
- api 2y ago
  Obligatory XKCD: https://xkcd.com/638/ https://xkcd.com/638/ I completely agree. We haven't been looking very long and very hard and we're not even that sure what to look for or where to look. All we can say right now is that we do not see any unambiguous signs of ETI, but space is called space for a reason. We are also searching the vastness of time. I don't completely dismiss ET-origin UFOs. I don't think there's anywhere near enough evidence to make such a claim as anything more than a hypothesis, but remember that one possible answer to the Fermi paradox is that there isn't one.
exochrono 2y ago
obligatory reference to the dark forest hypothesis (https://en.wikipedia.org/wiki/Dark_forest_hypothesis https://en.wikipedia.org/wiki/Dark_forest_hypothesis) as an alternate explanation for the apparent rarity of life

Galatians4_16 2y ago

> light hydrocarbons Sounds like Titan needs Democracy.

tshaddox 2y ago

> Of course life on Titan is convinced there could never be life here. The third planet is a literal hell where it rains molten dihydrogen monoxide in an atmosphere of corrosive oxygen. Any life there would vaporize and oxidize instantly. What are some of the chemicals that would vaporize and oxidize instantly in Earth’s atmosphere which this hypothetical Titan life could be made of?

dexwiz 2y ago
Almost any light hydrocarbon (4 carbons or smaller) vaporizes in the Earths atmosphere. Oxygen is pretty corrosive and we have all sorts of biological systems to slow or prevent this.
gus_massa 2y ago
> Any life there would vaporize and oxidize instantly. I don't expect a fast oxydation that set them in flames, but I expect them to fell what you would feel if you take a bath in bleach. To get a nice fire instantly on Earth, you need something like the substances in https://en.wikipedia.org/wiki/Autoignition_temperature https://en.wikipedia.org/wiki/Autoignition_temperature . The ones with low temperature are Triethylborane −20 °C (−4 °F): It looks like something that you could find in Titan, but I don't remember reading about that. The structure is not so weird, and there are some similar molecules with nitrogen instead of boron. I don't remember massive natural production of organic molecules with boron, but boron chemistry is very weird and well above my chemistry level. Silane 21 °C (70 °F): It would be more strange to have too many organic molecules with silicon. Phosphorus (white) 34 °C (93 °F): I don't think it's stable enough to be acumulated naturay. It's too energetic and I expect it to react with some of the molecules in Titan.

buu700 2y ago

I'm not sure if this is what you meant, but the concept of an alien species with a totally different subjective perception of time would be interesting. As in all of our actions/movements/speech would be experienced as being on e.g. 10x fast forward to them, or vice versa.

0cf8612b2e1e 2y ago
Dragon’s Egg is a story about this concept. Spoilers from the Wikipedia The rest of the story, including almost the whole history of cheela civilization, spans from 22 May 2050 to 21 June 2050. By humans' standards, a "day" on Dragon's Egg is about 0.2 seconds, and a typical cheela's lifetime is about 40 minutes.