Do we necessarily need to a planet to live on?

Like floating around in space in a spaceship?

@RayaHope Yes. Exactly.

I don’t think we could build something big enough to sustain the human race and hold the resources that we would need for any lengthy existence.

We do not, as long as we provide certain things to support homeostasis. In fact, I’m willing to wager that’s how we’ll be a space fairing civilization in the distant future if we make it that far.

We can’t manage to get along on a planet the size of earth. So, I don’t think stuffing 8 billion people into a spaceship is going to work very well. Then again, the elite don’t plan on taking us common folk with them!!! They are looking forward to setting up a New World Order without the riffraff.

If humans can master cold fusion then we will have available unlimited virtually free clean energy that could be used to build gigantic space crafts. With unlimited energy available our options become nearly unlimited. If some people decide that they would like to take off to live in space on their way to check out Alpha Centauri (about 4 light years away) then they’ll have that option. Terraforming Mars would be a piece of cake.

No. You can just build some O’neill cylinders. If you build them big enough, they can support entire ecosystems and artificial landscapes, as well as artificial gravity through centrifugal force.

@gondwanalon Well not so fast…Proxima Centauri is 4.2 light-years from Earth, a distance that would take about 6,300 years to travel using current technology. Such a trip would take many generations.

On a macro level, I would argue yes. As a sci-fi author, one can certainly assume you can create artificial gravity, a ship with perfect recycling, and so forth. But I would call that ‘sci-fi’ for now.

But you’re not supporting a large or expanding population that way. For that, you need habitable planets. And if you don’t have a large population…how long are you REALLY going to sustain that? How long before your population is inbred? How long before some TINY imperfection in your recycling causes the whole system to break down?

Your muscles could go to mush and your bone to cartilage, you would not be able to walk on Earth or any other planet.

@Tropical_Willie See @ragingloli ‘s answer. That’s essentially what I’m saying as well. Gravity wells are for suckers. We need to live on big hollowed out asteroids.

Explain to me how there could be a “hollowed out asteroid” with gravity.

@Tropical_Willie Rotation.

From what I have read, asteroids seem to be large rubble piles, large amounts of debris that coalesced into a larger mass, held together by mutual gravity, rather than monolithic rocks.
So if you you started to spin them up to speeds necessary to create artificial gravity, they would simply fly apart.

“Can we just live in deep space?”
– No, probably not.
– Watch (or re-watch) Silent Running for a science fiction notion of how that might work out, even with optimistic technology.

“Instead of terraforming another planet?”
– No, probably not.
– Trying to sustain life without any planet, poses many serious problems in terms of lack of resources, lack of gravity, lack of atmospheric protections against radiation and objects, lack of a variety of environments, etc.
– Terraforming a planet whose conditions are much farther from Earth-like, than Earth is, is VASTLY more work than maintaining life on Earth.

And, it looks doubtful that humans are even going to manage to sustain life ON EARTH. Good luck trying to do it WITHOUT EARTH.

The main advantage of leaving Earth, would be to get away from the foolish humans . . . but how would you even limit your expedition to non-foolish humans, and keep it that way?

@ragingloli Depends on composition and that varies. Some are essentially solid metal and could make good shelter.

@RayaHope Such is live on a space ship. It’s all about the journey not the destination. HA!

https://www.nasa.gov/hrp/bodyinspace This discusses challenges to people living long periods in space.

https://www.nasa.gov/sites/default/files/thumbnails/image/pinwheel_041119_me-01_0.png

This is a pinwheel summation of the TWINS STUDY which was done between Scott Kelly who spent 340 days on the international space station and his twin brother, Mark, who consented to be the control case on Earth.

I believe that long term life in space would result in genetic and other physiological changes in humans that may or may not be damaging and may or may not impact them from ever living in a normal planetary gravity again.

@gondwanalon We would have a very long journey so I guess we better enjoy ourselves. ;-)