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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

#61

Earlier quoted context omitted.

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

We are capable of rapidly changing chemical composition of atmosphere, which may be noticeable even at our technological level.

Plenty of lifeforms have changed the composition of the atmosphere. At faster rates than we are changing it now.

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

#62

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.

It would still be >124 years from the perspective of people on Earth, though.

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

#63
post #18

Firstly that is completely badass science. The idea that you can use observations to detect the chemical composition of an exoplanet millions of kilometres away is an absolute triumph of the work of thousands of people over hundreds of years. Really amazing and deeply humbling to me. Secondly, my prior was always that life existed outside of earth. It just seems so unlikely that we are somehow that special. If life d…

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…

Not so! Humans are just early: https://www.youtube.com/watch?v=l3whaviTqqg

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

#64
post #54

Earlier quoted context omitted.

While it has more time to become a red giant, it'll become more luminous over time and life on Earth will be impossible much earlier. I've seen estimates of 0.5B to 1.5B years.

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.

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

#65

Firstly that is completely badass science. The idea that you can use observations to detect the chemical composition of an exoplanet millions of kilometres away is an absolute triumph of the work of thousands of people over hundreds of years. Really amazing and deeply humbling to me. Secondly, my prior was always that life existed outside of earth. It just seems so unlikely that we are somehow that special. If life d…

> given how incredibly unfathomably vast the universe is ... we ...

But the probability of developing a highly developed civilization can be much, much smaller than 1 / number of planets in the universe.

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

#66
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.

And the evidence of that is what? What is the mechanism behind that? How is it testable?

This is what annoys me about this field. It is just magical thinking and baseless speculation. Random ideas get given names like "dark forest theory" like they are deep and consequential.

What you said is the only consequence of that "theory", because that "theory" is literally just the idle speculation that "alien civilizations may stay undetectable by hiding biological signatures of their worlds."

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

#67
post #18

Firstly that is completely badass science. The idea that you can use observations to detect the chemical composition of an exoplanet millions of kilometres away is an absolute triumph of the work of thousands of people over hundreds of years. Really amazing and deeply humbling to me. Secondly, my prior was always that life existed outside of earth. It just seems so unlikely that we are somehow that special. If life d…

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…

Maybe technology development is not exponential but s-curve. And anything large scale is impossible. So outside some radio signals there would not be any grand things that could be observed.

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

#68
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…

>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. Or they've reached their technological plateau millions of years ago. Like we did 50 years ago. >And the absence of those signs would be relatively strong evidence that life, while common, isn't long-lived. We know f…

> Or they've reached their technological plateau millions of years ago. Like we did 50 years ago.

What a bizarre thing to say, considering this very discovery leans on decades of science and engineering over the past 50 years!

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

#69
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.

Dark forest theory is wrong. Staying undetectable is always inferior to both staying undetectable and safely deploying varyingly detectable decoy targets at safe distance to probe the situation and gather intelligence.
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