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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

#231

Post by pfdietz »

bradleykingz wrote: post #212
TheOtherHobbes wrote: post #151

Earlier quoted context omitted.

Earth is on course to become uninhabitable for human civilisation its current form within a century, with an associated mass extinction. Even if all industrial activity stopped tomorrow there's now enough CO2 in the system to guarantee a succession of uncomfortable and expensive droughts, floods, storms, and wildfires for thousands of years. If it doesn't they will become more and more extreme very quickly. If ocean…

Indeed. Maybe once day, aliens will drop by and discover what remains of humanity. And stories will be told of how, when the time came, our species decided to bury its head in the sand and hope the problem would go away. Or maybe that we attempted to create god to come rescue us. Life imitates art. We refused to listen to the scientists.

Why do you think aliens will drop by? If aliens were visiting every planet in the universe, don't you think we would have noticed that by now? I mean, why didn't they visit the solar system and colonize it (and everywhere else) aeons ago?

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

#232

Post by pfdietz »

ninetyninenine wrote: post #149
trhway wrote: post #101

Earlier quoted context omitted.

>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.

Slow but plausible starships can be designed with 1960s technology. The obstacle is not the technology but the scale of the effort, a problem that could be solved by extension of civilization into the solar system with much larger populations.

https://galileo.phys.virginia.edu/classes/109.jvn.spring00/n...

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

#233

Post by [deleted] »

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.

[deleted]

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

#234

Post by psychoslave »

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…

Also even if it's low, it's not impossible that human technology actually is the one with the more advanced in its observable part of the universe.

That is, if there is supposedly one civilisation with clear advance in technology, it could just as well be humanity.

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

#235

Post by vladimirralev »

ivan_gammel wrote: post #102
vladimirralev wrote: post #69

Earlier quoted context omitted.

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.

Deploying decoy target requires more advanced technology (space travel) than hiding the signature (we may be able to do it long before we reach another star). I don’t think this is a good argument. Let’s say, some civilization decides to invest in decoy. It needs to shine brightly, the energy footprint is huge, a lot of work has to be done to transform the entire system. Then what? If there’s a hostile player, capabl…

Dark forest theory is about very advanced civilisations not engaging with anything around them. Limited resources are not an issue in this case. You can easily just do everything in parallel with AI or other automated control system, using stars as energy sources, including spawning whole decoy civilisations at different stages of development. Because we see so many stars we know nobody is running out of energy yet.

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

#236

Post by AlecSchueler »

DiogenesKynikos wrote: post #58
IsTom wrote: 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.

You're assuming we make it out of the industrial age while we backpedal on all of our climate commitments.

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

#237

Post by Andrew_nenakhov »

ninjagoo wrote: post #193
Andrew_nenakhov wrote: post #40

Earlier quoted context omitted.

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…

You may want to update your view that non-human animals lack sentience. [1] [1] https://pmc.ncbi.nlm.nih.gov/articles/PMC4494450/ If you're referring to technology/civilization-building capabilities, that is a different matter.

I owned quite a number of pets in my life, so I don't need explaining that they do have some kind of relatively high-order intelligence that allows them to do quite a lot of things. Yet, this is clear that no kind of animal on Earth but us exhibits potential to have capabilities to spread themeselves beyond home planet once it becomes uninhabitable. Moreover, signs show that once a type of species finds their niche, their intelligence levels off and does not tend to increase. In other words, modern crocodiles are no smarter than crocs from 10 millions of years ago, because they are doing mostly fine as they are.

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

#240

Post by layer8 »

tgv wrote: post #65
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…

> 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.

Even the probability of developing any life at all might be. We simply have no idea how rare it could be.
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