The Star at the End of Time

If we, or any conscious being is around to witness the very distant future our galaxy, what will they see? How long will life persist as the stars begin to die?

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For the sake of argument, let’s say that humanity survives the several ends of the world that await us. We somehow persist the gradual heating of our Sun and the evaporation of our oceans. Our descendants cling to existence through countless generations we watch the Andromeda galaxy merge with the Milky Way, forming a vast elliptical galaxy. We seek refuge in the outer solar system as the Sun finally expands into a red giant – twice! And finally our heirs or successors find new homes among the stars after the Sun’s final death and transformation into a dim white dwarf.

Hosted by Matt O'Dowd
Written by Drew Rosen and Matt O'Dowd
Graphics by Grayson Blackmon
Assistant Editing and Sound Design by Mike Petrow and Linda Huang

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[cheaterman]

I like this. It's not really a solution to the Fermi paradox from our viewpoint (in space-time), but at a cosmic scale, we might be the ancient aliens of the Milky Way.

[scientificlich]

So Lovecraft was wrong, if the bulk of life has yet to appear then that means... In the far future in the time of dimming Red dwarves, it is humans who shall be the ancient precursors. Bringing with us maddening tales of standard candles, galaxies, gravity waves detectors and eldritch technology to those unlucky enough to rouse us from our slumber in the dark.

[venceremosallende]

"When the last star blinks out, life must soon follow"

Isaac Arthur: Challenge accepted...

[thquark]

Imagine those civilizations, having close to no clue on what is the Universe: almost no stars in the sky, no galaxies around, even the CMB will be so faint.
That must be depressing.

[BickSnarf]

"One last long renaissance of life, as we huddle in the warmth of the last stars to burn in the darkening end of space time." That's a profound quote man.

[michaelblacktree]

It's interesting how the 'death throes' of a red dwarf roughly equates to half the lifespan of our own Sun.

[ABaumstumpf]

So 10 trillion years into the future:
Bob - "Hey John, John - wake up, i think i saw life evolving over there just now"
John - "Poor suckers, only got a few billion years left"

[Morilore]

I figured it out:

We need to stir the sun.

Someone bring me a very large spoon.

[UpcominLegend]

Red dwarfs be like "this isn't even my final form" lol

[BruceWayne-mbhk]

Isaac Arthur goes into detail on how we could outlive the stars.

[winstonknowitall]

"The Star at the End of Time" - sounds like a title of a SF novel.

[ebigunso]

*To all those who haven't watched Isaac Arthur yet:*
Go watch his "Civilizations at the End of Time" series for more stuff, extending even beyond the red dwarf stage of the Universe.

[nightmareTomek]

It's funny how the humans fear of death extends to the death of the whole universe.

[IlTrojo]

"Look", whispered Chuck, and George lifted his eyes to heaven. (There is always a last time for everything)

Overhead, without any fuss, the stars were going out.

[Restilia_ch]

So long as there's a restaurant at the end of the universe, we're good.

[FlamingAtheist]

and then we become sci fi dark souls, seeking out each dying flame in an ever dimming universe

[Netist_]

"When the last stars blink out, life is soon to follow." I think Isaac Arthur would beg to differ.

[srinitaaigaura]

That original research paper on red dwarfs and the end of their main sequence is extremely interesting. It talks about how after trillions of years of convective burning, slowly getting hotter how a radiative core finally forms in the last 500 billion years of burning when about 90% of the hydrogen is used up and how the stars get hotter and bluer in a way very similar to a Henyey track like larger stars do before fusion begins in their cores. But it also finds that as the mass of the stars increases, at the end they begin to swell up ever more until at 0.25 solar masses, they produce enough of a swell to make red giants. It even goes into detail of how and why red giants form at all - while the luminosity depends on the mass of the inert degenerate helium core, the more hydrogen is remaining in the envelope, the more opaque it gets and the more the star swells. This also explains why Wolf Rayet stars that lose their hydrogen outer layers are surprisingly small and hot and why stars with more metallicity can burn hotter. At the end, the fusion efficiency is remarkable -- a low mass red dwarf has successfully converted 99% of its hydrogen mass into helium! If that's not hacking physics, I don't know what is.

[Aethren]

"Hollow life, new rebirth
Set forth a soldier consumed by the earth
Burdened down, last to die
Laden with montrous souls deep inside
Sacrificed into flames
Now fed as kindling, they all burn the same
With warmth to stave off the end
I'll quench the cinders' desire to let there be fire again"

Aviators - Let there be Fire

Fitting song for a red dwarf hehe

[slavikvsvega]

Space time: "when the last stars blink out, life must follow".
Isaac Arthur: hold my black hole.