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Comment by phkahler | Hacker News Reader

According to the Wikipedia page Red Dwarf stars sound like they'll be around longer than our sun:

https://en.wikipedia.org/wiki/Red_dwarf

"Red dwarfs therefore develop very slowly, maintaining a constant luminosity and spectral type for trillions of years, until their fuel is depleted. Because of the comparatively short age of the universe, no red dwarfs exist at advanced stages of evolution."

And here I thought because of their small size they'd be LESS suitable for life.

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It's a complex issue:

https://en.wikipedia.org/wiki/Habitability_of_red_dwarf_syst...

It's interesting to think about the old maps with "here be dragons" around the edge... on tide-locked worlds such maps could effectively be true.

I like to think that there is a tidally locked planet somewhere out there whose inhabitants like to argue about whether life could ever evolve on a rotating planet.

"I mean, it would be so unstable! Even with a thick atmosphere, temperatures at one point would fluctuate by tens of degrees, hundreds of times a year! Plants would be unable to photosynthesise for half the time! Animals would be blinded!"

They also have TWO major drawbacks.

Habitable planets would orbit so close that they would likely be tidally locked, and one side would always face the star, while the other would always be dark. The temperature variation could pose major problems for habitability.

Red Dwarf stars are prone to intense flares, which could easily drive off an atmosphere.

Red Dwarf stars are likely not where we should look.

They're just red dwarf stars. Red Dwarf stars are stellar radio sources that continuously emit episodes of Red Dwarf. Those too are unsuitable for long term habitation.

This reminds me of when Comedy Central ran a week long Red Dwarf marathon. I think a week is probably the maximum habitable time period. The species known as cat could probably handle watching itself on TV for longer.

It's hypothetically possible that life as we know it could exist in the dim embers of stars a trillion years from now... it would be rare, it would be weird, but it could work.

The key is to remember that you have more than one variable to play with; it's not just overall stellar output, but orbital radius as well.

I wonder how well we'd adapt to living around a star with very different spectra than our own. For example, if it put out less blue light, would daytime suppress melatonin production as well as ours does? Then there's the different day length.

Not that either of those are in the top 1,000 problems of colonizing another system.

Why do we say the universe has a "comparatively short age" when we have no other universes to compare it to?

They're comparing the age of the universe (on the order of 10 billion years) to the expected lifetime of a red dwarf (on the order of a trillion years).

There is no reason to believe that the universe has a meaningful end, but it appears to have had some kind of origin less than 15 blya. Even if you posit proton decay and use heat death as and endpoint, you’re still talking about many more orders of magnitude of “future” than “past” and... well... what else do we mean when we say young?

If you use the Stelliferous Era [From 10^6 (1 million) years to 10^14 (100 trillion) years after the Big Bang. --wikipedia] as a meaningful period we are still at the very beginning, less than 0.0138% through.

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