Why Habitable Exoplanets Are Bad News

[Dutch Uncle]

I don't remember any functional adults on this board who invested so much emotion on who is thanking who's posts, are getting stressed about who "likes" who.

I certainly wouldn't expect it from a 'geochem' PhD.

Agreed on functional adults. The wackadoodles often focus on minutia. It's one reason why I think Perry is slipping his gears like my friend Randy.

 

[Cypress]

You have nothing to prove, Cypress. Your posts stand on their own. It's Perry who's fretting about how he's perceived by others.

BTW, please turn on your PM. I have an idea to share.

I think my Pms are set to only accept from people in my groups. I'll see if I can send you one and maybe you can reply

 

[Dutch Uncle]

I think my Pms are set to only accept from people in my groups. I'll see if I can send you one and maybe you can reply

IIRC, that didn't work before but it doesn't hurt to try.

 

[Dutch Uncle]

Why Habitable Exoplanets Are Bad News for Humanity's Future

Kepler-186f is the first planet almost exactly the same size as Earth orbiting in the “habitable zone.”

Last week, scientists announced the discovery of Kepler-186f, a planet 492 light years away in the Cygnus constellation. Kepler-186f is special because it marks the first planet almost exactly the same size as Earth orbiting in the “habitable zone” — the distance from a star in which we might expect liquid water, and perhaps life.

What did not make the news, however, is that this discovery also slightly increases how much credence we give to the possibility of near-term human extinction. This because of a concept known as the Great Filter.

The Great Filter is an argument that attempts to resolve the Fermi Paradox: why have we not found aliens, despite the existence of hundreds of billions of solar systems in our galactic neighborhood in which life might evolve? As the namesake physicist Enrico Fermi noted, it seems rather extraordinary that not a single extraterrestrial signal or engineering project has been detected (UFO conspiracy theorists notwithstanding).

This apparent absence of thriving extraterrestrial civilizations suggests that at least one of the steps from humble planet to interstellar civilization is exceedingly unlikely. The absence could be caused because either intelligent life is extremely rare or intelligent life has a tendency to go extinct. This bottleneck for the emergence of alien civilizations from any one of the many billions of planets is referred to as the Great Filter.

Are We Alone?
What exactly is causing this bottleneck has been the subject of debate for more than 50 years. Explanations could include a paucity of Earth-like planets or self-replicating molecules.

Other possibilities could be an improbable jump from simple prokaryotic life (cells without specialized parts) to more complex eukaryotic life — after all, this transition took well over a billion years on Earth.

Proponents of this “Rare Earth” hypothesis also argue that the evolution of complex life requires an exceedingly large number of perfect conditions. In addition to Earth being in the habitable zone of the sun, our star must be far enough away from the galactic centre to avoid destructive radiation, our gas giants must be massive enough to sweep asteroids from Earth’s trajectory, and our unusually large moon stabilizes the axial tilt that gives us different seasons.

These are just a few prerequisites for complex life. The emergence of symbolic language, tools and intelligence could require other such “perfect conditions” as well.

Or Is the Filter Ahead of Us?
While emergence of intelligent life could be rare, the silence could also be the result of intelligent life emerging frequently but subsequently failing to survive for long. Might every sufficiently advanced civilization stumble across a suicidal technology or unsustainable trajectory?

Continued
https://www.discovermagazine.com/th...-exoplanets-are-bad-news-for-humanitys-future

As previously discussed elsewhere, Fermi's Paradox is quite a conundrum if life is common in the Universe.

The link below discusses a few.

The Telegraph link came up with a pay wall so I included both it and the MSN version:

MSN

Aliens probably exist – but there’s a terrifying reason why we’ve never met them

Hollywood films may be filled with chest-bursting, face-hugging extraterrestrials yet, in real life, the silence from space is deafening

www.telegraph.co.uk

....In the summer of 1950, during a lunchtime conversation with his colleagues Edward Teller, Herbert York and Emil Konopinski, at Los Alamos National Laboratory, in New Mexico, the Italian-American physicist Enrico Fermi gave voice to the problem: “Where is everybody?”

The galaxy is old enough that other intelligent species capable of interstellar travel could have visited every star system many times over. Time enough has passed for galactic empires to rise and fall. And yet, when we look up, we find absolutely no evidence for them.

We started our hunt for alien civilisations using radio telescopes in the 1960s. Our perfectly reasonable attitude was: if we are here, why shouldn’t they be there? The possibilities for life in the cosmos bloomed all around us. We found that almost all stars have planets, and most have rocky planets orbiting the habitable zone around the star. Water is everywhere: there are several alien oceans we know of just in our own solar system. On Earth, microbes have been found that can withstand the rigours of outer space. The impacts of large meteor strikes have no doubt propelled them into space from time to time. Even now, some of the hardier varieties may be flourishing in odd corners of Mars.


All of which makes the cosmic silence still more troubling....

...Travel between star systems is a whole other order of impossible. Even allowing for the series’ dodgy physics, it remains an inconvenient truth that every time Star Trek’s USS Enterprise hops between star systems, the energy required has to come from somewhere. Is the United Federation of Planets dismantling, refining and extinguishing whole moons?

Life, even intelligent life, may be common throughout the universe – but then, each instance of it must live and die in isolation. The distances between stars are so great that even radio communication is impractical. Civilisations are high-energy phenomena, and all high-energy phenomena burn out quickly. By the time we receive a possible signal from an extraterrestrial civilisation, that civilisation will most likely already be dead...

 

[Cypress]

As previously discussed elsewhere, Fermi's Paradox is quite a conundrum if life is common in the Universe.

The link below discusses a few.

The Telegraph link came up with a pay wall so I included both it and the MSN version:

MSN

Aliens probably exist – but there’s a terrifying reason why we’ve never met them

Hollywood films may be filled with chest-bursting, face-hugging extraterrestrials yet, in real life, the silence from space is deafening

www.telegraph.co.uk

....In the summer of 1950, during a lunchtime conversation with his colleagues Edward Teller, Herbert York and Emil Konopinski, at Los Alamos National Laboratory, in New Mexico, the Italian-American physicist Enrico Fermi gave voice to the problem: “Where is everybody?”

The galaxy is old enough that other intelligent species capable of interstellar travel could have visited every star system many times over. Time enough has passed for galactic empires to rise and fall. And yet, when we look up, we find absolutely no evidence for them.

We started our hunt for alien civilisations using radio telescopes in the 1960s. Our perfectly reasonable attitude was: if we are here, why shouldn’t they be there? The possibilities for life in the cosmos bloomed all around us. We found that almost all stars have planets, and most have rocky planets orbiting the habitable zone around the star. Water is everywhere: there are several alien oceans we know of just in our own solar system. On Earth, microbes have been found that can withstand the rigours of outer space. The impacts of large meteor strikes have no doubt propelled them into space from time to time. Even now, some of the hardier varieties may be flourishing in odd corners of Mars.


All of which makes the cosmic silence still more troubling....

...Travel between star systems is a whole other order of impossible. Even allowing for the series’ dodgy physics, it remains an inconvenient truth that every time Star Trek’s USS Enterprise hops between star systems, the energy required has to come from somewhere. Is the United Federation of Planets dismantling, refining and extinguishing whole moons?

Life, even intelligent life, may be common throughout the universe – but then, each instance of it must live and die in isolation. The distances between stars are so great that even radio communication is impractical. Civilisations are high-energy phenomena, and all high-energy phenomena burn out quickly. By the time we receive a possible signal from an extraterrestrial civilisation, that civilisation will most likely already be dead...

Thanks for that.

Hopefully, primitive life exists on the ocean worlds of this solar system. If not, we might have to rethink our assumptions for how readily life can arise in the presence of liquid water.