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“Most promising signs yet” of alien life on a planet beyond our Solar System

skyatnightmagazine.com

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Re: “Most promising signs yet” of alien life on a planet beyond our Solar System

#71

Post by lucb1e »

londons_explore wrote: post #21

This is happening 124 light years away from earth. That means if we develop a way to make a space ship accelerate at 1g for a long period of time, you could go there in just 10 relativistic years. Unfortunately, whilst science allows such a rocket, our engineering skills are far from being able to build one.

If you find that sort of thing interesting... I don't always know how seriously to take the things on this channel, but I discovered Fraser Cain not so long ago and find the ideas mentioned in the interviews to be fascinating, for example "Interstellar Travel Without Breaking Physics with Andrew Higgins" https://www.youtube.com/watch?v=SkGRVvA23qI (warning: it's over an hour)

Re: “Most promising signs yet” of alien life on a planet beyond our Solar System

#72

Post by ta8645 »

mnky9800n wrote: post #28
ta8645 wrote: post #18

Earlier quoted context omitted.

If life is very common in the universe, then that is probably bad news for us. It means that civilizations should exist that are millions of years more technologically advanced than us; and should be leaving telltale signatures across the sky that we'd likely have detected by now. And the absence of those signs would be relatively strong evidence that life, while common, isn't long-lived. Suggesting that our demise t…

Most of the sky is left unexplored. I think it’s premature to suggest we don’t see things. There are too many things to see in a single lifetime.

But if there was a Kardashev type III civilization in the Milky Way, they would have had full control of our entire galaxy in a mere 200 million years or so. And we can be pretty sure that such a civilization doesn't actually exist. Which suggests that either advanced life is rare, or dies off long before it ever reaches such technological breadth.

Re: “Most promising signs yet” of alien life on a planet beyond our Solar System

#73

Post by cedilla »

ivan_gammel wrote: post #49
ta8645 wrote: post #18

Earlier quoted context omitted.

If life is very common in the universe, then that is probably bad news for us. It means that civilizations should exist that are millions of years more technologically advanced than us; and should be leaving telltale signatures across the sky that we'd likely have detected by now. And the absence of those signs would be relatively strong evidence that life, while common, isn't long-lived. Suggesting that our demise t…

> And the absence of those signs would be relatively strong evidence that life, while common, isn't long-lived. If dark forest theory is right, alien civilizations may stay undetectable by hiding biological signatures of their worlds.

The dark forest theory makes for a great book premise, but it probably doesn't apply in real life simply because the distances are so far.

The universe is not a forest. It's a gigantic, empty ocean. The next, dangerous tribe is not lurking behind a bush 2 meters away, but is sitting on an island that's so far away it will take centuries to go there, if it is possible at all

Re: “Most promising signs yet” of alien life on a planet beyond our Solar System

#74

Post by sjducb »

martopix wrote: post #47
aardvark179 wrote: post #27

Earlier quoted context omitted.

You seem to be conflating life, multicellular life, and intelligent life. Life appears to have developed on Earth pretty quickly, multicellular life took a long time to appear, and we are only aware of one species that developed civilisation building capabilities. Life might be very common, but intelligent life still be incrediblY rare.

It depends what you mean by "civilization building". I think we gloss over that a bit too much. We're not the largest population, not the largest total mass, not the only one that builds large structures. We're the only one that sent stuff outside of Earth, yes, and a few other things. But discussing the definition is itself interesting

If you include our crops and livestock then our civilisation has about half the land biomass. 38% of the earths land is farmland. (We use the richest parts as farmland) https://www.ncesc.com/geographic-faq/what-percentage-of-land...

Another 34% is Forrest, much of which is managed for logging.

Re: “Most promising signs yet” of alien life on a planet beyond our Solar System

#75

Post by mr_mitm »

londons_explore wrote: post #21

This is happening 124 light years away from earth. That means if we develop a way to make a space ship accelerate at 1g for a long period of time, you could go there in just 10 relativistic years. Unfortunately, whilst science allows such a rocket, our engineering skills are far from being able to build one.

Calling it simply an engineering issue is not properly conveying the ridiculousness of such a journey. For a small space ship of 1000 tons, this would take ten thousand times the current yearly energy consumption of mankind. So we'd need to figure out how to generate the energy and then store it on a space ship before even thinking about the engineering.

And that's ignoring the mass of the fuel. The classical rocket equation has the mass going exponentially with the velocity, which makes this endeavor even more mind bogglingly ridiculous. We'd actually need 2 million years worth of our current yearly energy consumption.

It's fun to think about, but being clear about the challenges puts quite the damper on it.

Re: “Most promising signs yet” of alien life on a planet beyond our Solar System

#76

Post by xrisk »

poulpy123 wrote: post #53
allan_s wrote: post #33

Earlier quoted context omitted.

actually we know how to produce it without involving living organism https://en.wikipedia.org/wiki/Dimethyl_sulfide#Industrial_pr...

actually a living organism is needed to produce it this way

Wikipedia says "In industry dimethyl sulfide is produced by treating hydrogen sulfide with excess methanol over an aluminium oxide catalyst”.

Which part requires a living organism?

Re: “Most promising signs yet” of alien life on a planet beyond our Solar System

#77

Post by StopDisinfo910 »

tomelders wrote: post #25

My understanding is that the great filter theory means this is bad news for us humans here on earth. And considering the state of the world right now, it's especially ominous. Fate loves irony.

The great filter is only one of the possible explanations of the Fermi paradox however. There are other far less bleack including that there is actually no paradox at all: life is indeed frequent and but we are just bad at detecting it/have not been looking for it long enough.

Re: “Most promising signs yet” of alien life on a planet beyond our Solar System

#78

Post by Nevermark »

meindnoch wrote: post #64
DiogenesKynikos wrote: post #58

Earlier quoted context omitted.

In 500 million years, hopefully humans (or whatever humans have become at that point) will be able to modify the Earth's atmosphere to deal with the increased luminosity of the Sun.

We'll put a giant sunshade in the Earth-Sun L1 Lagrange point.

We might need to do that by the end of this century.

If we are able to harvest the solar system resources it would take by then.

Trial run for the bigger “solar warming” event.

Re: “Most promising signs yet” of alien life on a planet beyond our Solar System

#79

Post by [deleted] »

allan_s wrote: post #33
metalman wrote: post #19

Earlier quoted context omitted.

only know to be produced.....is a whoa bessy phrase,?¿ as in 70 years ago an undergraduate figured out that dimethyl sulfide was produced by living organisms and he asked his professor what else made it, and got shrug and "nothing else I know of" and everybody has been cutting and pasting since, OR, an international team spent years and millions working on the chemistry behind dimethyl sufide in an epic known to all…

actually we know how to produce it without involving living organism https://en.wikipedia.org/wiki/Dimethyl_sulfide#Industrial_pr...

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