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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

#141

Post by cedilla »

autonomousErwin wrote: post #125
cedilla wrote: post #73

Earlier quoted context omitted.

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

Isn't that the point of the dark forest theory? It's not the fact that there is a dangerous tribe behind a bush it's more that you don't know if they're dangerous or not so you have to err on the side of caution - because you don't know if they're doing the same. It's the whole chain of suspicion theory that it's safer to shoot first and then ask questions later because the speed you can communicate is the same speed…

Yes, but the next bush is dozens of light years away. The analogy breaks down because the distances are different in quality.

The only reason why this becomes such a problem in the Three-Body-Problem is the existence of magic in that universe. Thinking protons, instant communication, folded dimensions, easy interstellar travel, it's all interesting speculation inspired by physics, but incompatible with our actual universe.

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

#142

Post by bathtub365 »

sph wrote: post #9

A bit clickbaity of OP to skip the operative word ‘promising’ signs of life.

And it isn’t actually signs of life. The first paragraph:

> Astronomers say they've found "the most promising signs yet" of chemicals on a planet beyond our Solar System that could indicate the presence of life on its surface.

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

#144

Post by energy123 »

Andrew_nenakhov wrote: post #40
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…

It is quite plausible that life is abundant, but sentience is not. If we take Earth, it formed 4.5 billions years ago, conditions became suitable to support life like 4B years ago and first known signs of life are dated 3.7B years ago. Now, in just .5B years Earth would likely become uninhabitable due to Sun becoming a red giant. In other words, on Earth life spent 90% of its total available time before sentience eme…

This is now much less plausible. Intelligence, like eyesight, is believed to be a result of convergent evolution[0].

[0] https://www.quantamagazine.org/intelligence-evolved-at-least...

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

#145

Post by ninetyninenine »

ta8645 wrote: post #18
seanhunter wrote: post #6

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…

The probability of advanced civilization is given the probability of life is quite low itself.

For the overwhelming majority of time life has existed on earth only a minuscule part of it involved civilization. And an even more minuscule part of it involved technology that has a small chance to send a coherent signal to another star.

Our future is easily estimated by the hardness of traveling through space and the demise of our sun. Probability points to the end humanity by way of the death of our star. We are statistically most likely to end.

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

#146

Post by perihelions »

weberer wrote: post #5

Here's the primary source https://iopscience.iop.org/article/10.3847/2041-8213/adc1c8 They possibly detected dimethyl sulfide, which is only known to be produced by living organisms.

I'm not convinced about the methods. It looks a lot like p-hacking to me: they have a highly specific hypothesis drawn from a large universe—that dozen or so molecules (§3.1) in their infrared spectrum model they're fitting experimental data against. I don't buy the way they created that hypothesis. The put a handful of highly specific biosignature gases into it, things that were proposed by exobiology theory papers. One very specific hypothesis out of many, and a low likelihood one. And that's the hypothesis they get some borderline ~3σ signals for? Really?

edit: Any chance someone might have the charity to explain why my criticism is so far off-base, according to the HN consensus?

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

#147

Post by Imustaskforhelp »

nurettin wrote: post #30
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…

Not to take away from you personally, but civilization as we understand it is our own cliche. Organisms developed on different planets could absolutely have a different view on life and society in general. Even on earth we have highly intelligent and physically capable organisms that care naught for your conceptions of how groups should function together. There are even organisms that seem to have no intersection wit…

Regarding populating earth and invading space.

I was just watching the original (first) matrix movie yesterday because I was just too bored.

And there was this dialogue by Agent Smith:- ```I’d like to share a revelation during my time here. It came to me when I tried to classify your species. I realized that you’re not actually mammals. Every mammal on this planet instinctively develops a natural equilibrium with the surrounding environment but you humans do not. You move to an area and you multiply and multiply until every natural resource is consumed. The only way you can survive is to spread to another area. There is another organism on this planet that follows the same pattern. Do you know what it is? A virus. Human beings are a disease, a cancer of this planet. You are a plague, and we are the cure.```

So yea, I totally agree with you because just as how Agent Smith compared Humans to a virus and just like we know that not every living thing is a virus, In a similar fashion, I think not every species have intersection with our sets of interests (populating earth,invading space).

I actually had just watched matrix for agent smith actually. I don't know why but the guy looks really cool to me for some reason.

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

#148

Post by nbadg »

ta8645 wrote: post #18
seanhunter wrote: post #6

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…

I often wonder if the answer to the Fermi paradox isn't just as extremely banal as "turns out that interstellar exploration just isn't economically viable". I think it's entirely plausible that advanced economies are circular, and that within a circular economy, it's just extremely difficult to justify the massive expenditure of resources that it would take to become interstellar.

I mean, think about how many stars had to align to catalyze our first steps on the moon. Now, 53 years later, we're just starting to put serious effort into going back -- not because there's any market reason to do so, but because (once again) there's political pressure for it. Which would suggest that the best case scenario for the current exploration efforts are something along the lines of what we already see in Antarctica: a well-staffed scientific presence that does really cool/valuable work, but nothing remotely approaching even a single major city in terms of human presense.

It seems to me that one of the unwritten priors to the Fermi paradox (at least in popular discourse) is that technology is the only prerequisite to expanding a civilization; in other words, if you have the technology, then interstellar expansion is only a matter of time, and that all civilizations will inevitably eventually develop the technology. And that... seems like a pretty big assumption, if human history is any indication.

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

#149

Post by ninetyninenine »

trhway wrote: post #101
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.

>we are only aware of one species that developed civilization building capabilities. well, the first one just doesn't leave any chance for any other one. >Life might be very common, but intelligent life still be incrediblY rare. the time period between big ape and nuclear bomb is extremely short - few millions years. In a hundred or a thousand - doesn't really matter - years we'll be an interstellar species or may be…

Unlikely we will ever be interstellar. The technology involved is speculative and the physics barriers needed to be surpassed are impossible and not well understood.

To reach another star by the laws of physics involves many human lifetimes and that’s just the nearest star.

That in itself makes it more likely that we will never be interstellar.

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

#150

Post by farmdve »

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.

Sadly it is still only a stop-gap measure. The sun is for all intents and purposes, dying a slow death.
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