Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost • Hacker News Board

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#31

Post by nerfhammer » Mon, Nov 13, 2017, 9:36 PM UTC

pavel_lishin wrote: post #20

delecti wrote: post #16

Earlier quoted context omitted.

Well one factor would go up (planets with life 1>2) and another would go down (planets with life developing intelligence 1>0.5), resulting in a wash. It does move towards giving additional degrees of freedom on those terms though, making the equation as a whole slightly less pseudo-science.

Depends on their intelligence if we find them, right? They might be intelligent and tool-using, but hampered by their aquatic origins.

Basically. Dinosaurs ruled the earth for 150 million years. If the asteroid had never hit the Earth, maybe they still would. The earth is probably only inhabitable for another billion years or so and has been inhabitable for 4 billion years, so we're 80% of the way through the Earth's habitable life.

Maybe it's not atypical that life-bearing planets don't end up producing a technologically advanced one. The Earth is an example of how a planet can have complex animal life for hundreds of millions of years without any of them being able to invent cake, and habitability is relatively temporary.

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#32

Post by mojomark » Mon, Nov 13, 2017, 9:37 PM UTC

nerfhammer wrote: post #19

mirimir wrote: post #4

I'm reminded of the argument[0] that conscious beings that evolved on worlds like this will be very freaked by the discovery of stuff above the ice. Seeing planets and stars, we humans have always had some sense that there's more to the Universe than Earth. 0) The Killing Star by George Zebrowski and Charles Pellegrino

Is there any light down there? Would they have eyes? Stars etc. might be more like totally abstract theoretical concepts like quantum physics is to us, or at least X-rays. They might not be able to literally look up and see things, having mostly only sonar, hearing, and touch senses; handfuls of surface-explorers wearing special environment suits report the utterly strange sensation that space seems almost totally tw…

The sun isn't the only source of radiant energy (visible light, IR, UV, etc) in a planetary system. Chemoluminescence and indeed heat itself (infrared (IR) emission) are other sources. I would think that living in a thermal environment closed off from the sun, creatures would be likely to evolve bioluminescent emitters/receptors or even fully developed IR Eyes in order to gain survival advantage.

1.) https://voices.nationalgeographic.org/2014/03/14/from-night-...

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#33

Post by crusso » Mon, Nov 13, 2017, 9:38 PM UTC

Is there a protocol for looking for life in an environment like Enceladus that would sufficiently guarantee sterility of the probe?

It seems that guaranteeing sterility would be sufficiently impossible to render Enceladus permanently unapproachable.

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#34

Post by cavanasm » Mon, Nov 13, 2017, 9:43 PM UTC

rdruxn wrote: post #14

mirimir wrote: post #4

I'm reminded of the argument[0] that conscious beings that evolved on worlds like this will be very freaked by the discovery of stuff above the ice. Seeing planets and stars, we humans have always had some sense that there's more to the Universe than Earth. 0) The Killing Star by George Zebrowski and Charles Pellegrino

I always loved this portion of The Ellimist Chronicles, one of the companion books to the Animorph Series. If I remember correctly, these god-like beings play simulated games where they develop species over eons and during one game, the catalyst the main character needed to advance his civilization was parting the perpetual clouds so his species could witness the stars and for the first time, look up.

I remember that one. The game is that you can make one single change to species/environment, and he parts the clouds. His opponent ups aggression, and his opponent's species wipes his out. They send their game out into space, and another species gets the game, thinks the game is altering real species causing drama.

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#35

Post by losteric » Mon, Nov 13, 2017, 9:43 PM UTC

delecti wrote: post #16

drewrv wrote: post #15

If alien life were discovered within our solar system, I wonder what the implications for the Drake Equation would be. Assuming panspermia is ruled out, the fact that abiogenesis occured twice within a seemingly ordinary system would imply life is incredibly common.

Well one factor would go up (planets with life 1>2) and another would go down (planets with life developing intelligence 1>0.5), resulting in a wash. It does move towards giving additional degrees of freedom on those terms though, making the equation as a whole slightly less pseudo-science.

The known probabilities will go down, but that evidence is very weak with a sample size of Personally, I've always assumed less than 100% of life-bearing planets will have intelligent life. Earth would have failed less than 1M years ago, and our species may not be around for long.

The interesting question, to me, is how often does life arise? If we find two origins in our solar system... that would change everything.

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#36

Post by drewrv » Mon, Nov 13, 2017, 9:45 PM UTC

delecti wrote: post #16

drewrv wrote: post #15

If alien life were discovered within our solar system, I wonder what the implications for the Drake Equation would be. Assuming panspermia is ruled out, the fact that abiogenesis occured twice within a seemingly ordinary system would imply life is incredibly common.

Well one factor would go up (planets with life 1>2) and another would go down (planets with life developing intelligence 1>0.5), resulting in a wash. It does move towards giving additional degrees of freedom on those terms though, making the equation as a whole slightly less pseudo-science.

It would only be a wash if you currently believe the chance of developing intelligence is > 50%. To me, the fact that intelligence is rare on earth makes me think the odds of developing intelligence elsewhere is rare too.

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#37

Post by debatem1 » Mon, Nov 13, 2017, 9:55 PM UTC

dogma1138 wrote: post #29

bochoh wrote: post #28

Earlier quoted context omitted.

Is is intriguing to me to consider the limitations of space travel if you were an aquatic organism. Simply moving that much of any fluid versus empty "air" space would make leaving your planet that much more difficult. That's not to mention the inherent issues of electricity and developing circuits underwater.

Underwater technological civilization isn’t possible, tool making is very limited, no fire, no complex chemistry, no real evolutionary path to a technological advance society without uplifting. While possibly there aren’t that many restrictions on where life can evolve and even where can different levels of intelligence can evolve there are likely quite a bit of restrictions on where and how technological intelligenc…

Why are you confident that underwater technical civilization isn't possible?

It would seem to me that techniques like hydraulics would emerge quickly, and large pressure and temperature differentials over small distances are considerably more common and easier to harness underwater than above. Fabrication is certainly harder, but not impossibly so. Some weapons like thrusting spears might be easier to make and more advantageous in the water than on land, and those developed pretty early for us.

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#38

Post by [deleted] » Mon, Nov 13, 2017, 10:00 PM UTC

delecti wrote: post #16

drewrv wrote: post #15

If alien life were discovered within our solar system, I wonder what the implications for the Drake Equation would be. Assuming panspermia is ruled out, the fact that abiogenesis occured twice within a seemingly ordinary system would imply life is incredibly common.

Well one factor would go up (planets with life 1>2) and another would go down (planets with life developing intelligence 1>0.5), resulting in a wash. It does move towards giving additional degrees of freedom on those terms though, making the equation as a whole slightly less pseudo-science.

[deleted]

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#39

Post by foreigner » Mon, Nov 13, 2017, 10:02 PM UTC

Why do these articles always assume that if we find anything it will just be microbial? There could be anything at all down there.

Re: Chances of E.T. Living Subsurface Ocean of Enceladus Given Major Boost

#40

Post by XR0CSWV3h3kZWg » Mon, Nov 13, 2017, 10:15 PM UTC

foreigner wrote: post #39

Why do these articles always assume that if we find anything it will just be microbial? There could be anything at all down there.

Most of life's time on earth was single celled (life started ~4.1 Billion years ago, multi-cellular ~1.7 Billion years ago). If the world wasn't filled with O2 or sexual reproduction didn't start life on earth could still be single celled.