[cletus]

It's not even a question: the Earth is absolutely facing the same fate. The Sun is getting hotter and in ~1 billion years the Earth will be uninhabitable by us in its current form.

Eventually (~4-5B years) the Sun will expand while in its dying stages and probably swallow the Earth.

What can we do? That's actually quite "easy". I mean "easy" in the essence that no weird new physics is required, it's just an engineering problem, albeit a massive one. Then again, we have a lot of time. So there are essentially three things we can do:

1. Reduce the amount of light and heat hitting the Earth. Example: large arrays of solar power collectors at the L1 Lagrange point. If the Sun is 10% hotter in 1B years and you reduce the light hitting the Earth by ~10% it about evens out. The captured energy can be put to use and I expect it wouldn't even be noticeable from Earth. The Sun will just be slightly dimmer;

2. You can move the Earth. Many people are familiar with gravity assists for spacecraft. Obviously gravity affects both bodies but the spacecraft is so low-mass it has no discernable effect on the larger body. Imagine taking large rocks and flying them past the Earth. The net interaction can be that the Earth moves slightly faster. Do this over a long enough time frame and you can move the Earth's orbit outwards.

3. The Sun itself can be manipulated to remove mass from it, particularly Helium.

A lot can be done in a billion+ years.

[T-A]

> A lot can be done in a billion+ years.

Indeed, to the point that talking about it in terms of what "we" could do about it in ordinary engineering terms becomes pointless.

A billion years ago, the first multicellular plants were beginning to move onto land; animals were still water-bound single cells who would have to wait another couple hundred million years to discover sex. Whatever life still exists on Earth a billion years from now will presumably be as far removed from us as we are from those ancient ancestors.

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

[jjcon]

Very interesting - couldn't we also just evolve to live with a hotter sun in a billion years or will it affect other systems so much that life for humanoids will be more difficult?

[cletus]

A lot of problems ultimately turn into energy problems.

Lack of recycling comes down to it mostly being uneconomic to do so. There can be a labor component to this too but the energy cost matters. A lot of labor can be automated, which then also becomes an energy problem.

It's highly likely that in 1B years, we'll have access to energy many orders of magnitude higher than we do now and it'll probably be much cheaper. My personal prediction is the space-based solar power collection is likely to be dominant. The big unknown is fusion. Personally I'm not yet convinced fusion will ever be economical, but that's a whole other topic.

We live in hot, dry climates now (eg the Middle East). What makes that possible is simply energy for food and water production, climate control and so on.

It'll likely be worse for other life on Earth but that too is an energy problem. Also, we have no real idea of what life will look like in 1B years since we'll likely have gone through several mass extinction events between now and then.

And of course, in the last 1B years we've largely gone from single-celled and early multi-cellular organisms to what we have now.

[rowanG077]

Evolution like that won't happen in a modern society like we have where we care for everyone and fight against nature.

I'd imagine evolution is possible but only under collapse of civilization as we know it.

[cletus]

So this opinion is a fairly popular one but I'm not sure there's any factual basis for it.

The idea is simple: there's little evolutionary pressure to adapt because technology and society can deal with issues that once would've been fatal.

There are a bunch of issues that still affect survivability though: recklessness, propensity for violence, inability to survive in modern society, addiction issues, mental health issues, etc. We can expect all of these to improve but go away entirely? That's less certain.

Even if you ignore mortality issues, the other side of natural selection is how many offspring you have and how many of them survive to have their own offspring. If a group with trait A has an average of 2 children each but trait B have an average of 3, it's not too many generations before B becomes dominant.

Evolution is also relatively slow and not smooth. We only identified DNA ~50 years ago and mapped the human genome in the last 10-15. It's a bit early to refute observational evidence.

Remember too that certain traits that were once advantageous can become a disadvantage or they only become a disadvantage in certain circumstances. Take the modern abundance of food. Some people have genes that predispose them to storing excess, others less so. 1000 years ago, that was probably an advantage. Now? Less so, both in terms of health effects related to, say, obesity, but also in terms of finding a mate and having offspring given changing societal standards for beauty (not universal of course).

[rowanG077]

Oh definitely. I didn't mean evolution is halted. I mean evolution that would protect us better against the elements in this case.

[GekkePrutser]

But in such a society we'll figure out how to adapt ourselves using DNA modification, doing evolution's job for it. We're getting pretty close already and a billion years is more than enough.

But we'll have other challenges first like finite resources and our self-destructive tendencies. We'll have made bigger fish to fry before we can even make it a billion years

[jeffdn]

The combination of two processes -- tectonic activity and the increased luminosity of the sun -- will mean that surface water no longer exists at that time.

[yosito]

> in ~1 billion years the Earth will be uninhabitable by us in its current form

In ~1 billion years, "we" won't be inhabiting anything in our current form. If humanity/primates haven't gone extinct by then, they will have evolved completely beyond our current form.

[idiotsecant]

4. Develop into a matrioshka brain civilization and mine all the rocky planets for materials to convert to solar computronium.

A billion years is a long time. I feel like this or extinction are the only two real scenarios.