What's NASA Up To And Other Space Stuff

[Flixy]

Forgot to reply earlier, but:

I forgot to write that I think artificial habitats are a more realistic prospect for human space habitation than living on planetary surfaces, in this or any other system.

P.S. if you put engines on a space habitat now it's called a generation ship.



I think the idea of a permanent presence on Mars al la Antarctica (these places have quite a lot in common actually) is a good idea, I just don't think a proper colony with people being born, living out their lives and dying there is viable - unless I'm wrong about the gravity thing, which I'm very happy to be.



I did.



I'm not so sure. If you can go 0.8 or 0.9c with some futuristic proposition drive then I think the time dilation gets to the point where the travellers should live to see their destination. The logistical challenge for going to nearby stars is the same as the one for going to distant stars; you just need to be able to build a ship that'll keep people alive for years or decades.

But you wouldn't be expanding your own civilisation that way, just starting new ones.

Your other option is you colonize nearby habitable exoplanets, wait a couple of centuries until they're supporting developed cultures of their own then *they* send out colony ships to worlds near to them and so on and so on. After a few million years of this, your dudes are probably on a significant %age of the milky way.

Regarding the gravity thing, obviously it's all unknown at this point. But from what I've read, most designs for, say, rotating spacecraft, aim for a much lower gravity and it's assumed/hoped that this will be enough. Most problems come from a lack of gravity (fluids not going to the proper places etc.) and are thought to be much less of a problem if you have at least some gravity. But of course this has not been tested yet. Obviously an Antarctica like base would also come before any actual colonization. But still, any problem you'll encounter trying to colonize other planets in our solar system are likely also encountered on exoplanets (unless you're extremely lucky and find a copy of Earth nearby), so I think it makes sense to try it here first. If you can do it here, you might be able to do it in another solar system. but if you can't even do it here, where the distances are relatively short and there's at least some prospect of direct aid, or even evacuation if it all goes wrong. So I think colonization in our solar system is basically an essential step to colonizing exoplanets. And even if you don't want to go terraforming and colonizing planet surfaces, you probably still want to try it out in nearby space before flying to the next solar system with nothing more than hope to try and make it.

And again, that big 'if' in 'if you can go 0.8 or 0.9c', it's a big if to speculate about future propulsion. I'm a bit rusty on time dilation etc. so I'm not sure if you're correct on that.

Lastly, if you're not going to expand your civilization but starting a new one.. Bluntly put, would a society be willing to pour vast resources into a project like that, which does not have any added benefit for their own civilization? Sure, it'd be cool, but would that warrant the presumably vast expenses? The Apollo project took NASA funding to almost 5% of US budget, but at least had direct benefit and prestige in the cold war.

[Steely Glint]

Regarding the gravity thing, obviously it's all unknown at this point. But from what I've read, most designs for, say, rotating spacecraft, aim for a much lower gravity and it's assumed/hoped that this will be enough. Most problems come from a lack of gravity (fluids not going to the proper places etc.) and are thought to be much less of a problem if you have at least some gravity. But of course this has not been tested yet.

Astronauts on the ISS currently do 6 months tours in microgravity and this is enough for noticeable but not serious health effects. For spacecraft that produce gravity, but lower than earth's, will presumably mitigate health problems to the extent that missions measured in years will be possible without astronauts suffering too badly. But over the course of human-life time, I believe there is a good chance that 0.4g is going have an impact on people living on Mars and people born on Mars. No one will want to go and live and have children on Planet Osteoporosis.

Obviously an Antarctica like base would also come before any actual colonization. But still, any problem you'll encounter trying to colonize other planets in our solar system are likely also encountered on exoplanets (unless you're extremely lucky and find a copy of Earth nearby), so I think it makes sense to try it here first.

Here's the thing: I don't think any space colony has a hope of being sustainable unless it has a genuine economic reason to exist; after the first few generations the population will just drift away otherwise. "to try it out for when we do it on exoplanets" is not a genuine economic reason; the people are there for the sake of being there, not because there's some advantage to being there. I don't say such a thing couldn't or shouldn't happen, I can picture NASA or someone doing exactly that, a little model community on Mars made up of volunteers to study long term effects of life on Mars on human beings. But that wouldn't be a true, self-sustaining colony that could survive if something bad happened to the Earth.

Lastly, if you're not going to expand your civilization but starting a new one.. Bluntly put, would a society be willing to pour vast resources into a project like that, which does not have any added benefit for their own civilization? Sure, it'd be cool, but would that warrant the presumably vast expenses? The Apollo project took NASA funding to almost 5% of US budget, but at least had direct benefit and prestige in the cold war.

Society isn't a monolith. Some entities in society made decide they just don't like the way things are being run around here (here = Sol) and take off in a generation ship.

[Wraith]

Astronauts on the ISS currently do 6 months tours in microgravity and this is enough for noticeable but not serious health effects. For spacecraft that produce gravity, but lower than earth's, will presumably mitigate health problems to the extent that missions measured in years will be possible without astronauts suffering too badly. But over the course of human-life time, I believe there is a good chance that 0.4g is going have an impact on people living on Mars and people born on Mars. No one will want to go and live and have children on Planet Osteoporosis.

I always got the impression that a lot of the biggest problems with lower gravity stem from expecting the astronauts to return to Earth. If there's no such expectation, then it's not as big a deal if you adapt to lesser gravity.

Here's the thing: I don't think any space colony has a hope of being sustainable unless it has a genuine economic reason to exist; after the first few generations the population will just drift away otherwise. "to try it out for when we do it on exoplanets" is not a genuine economic reason; the people are there for the sake of being there, not because there's some advantage to being there. I don't say such a thing couldn't or shouldn't happen, I can picture NASA or someone doing exactly that, a little model community on Mars made up of volunteers to study long term effects of life on Mars on human beings. But that wouldn't be a true, self-sustaining colony that could survive if something bad happened to the Earth.

A Martian space elevator can be built with currently existing materials.

Totally agree that new colonies won't survive without an economic reason to exist. We don't want Space Detroit.