very alarming..

[GUNWOUNDS]

Yes i agree... the ocean increases pressure as you continue to submerge... too many variables to consider... space void is one pressure..... easier to plan for.

[MrFlibble]

On the other hand, there might be salvageable resources in the depths that would make submarine colonization cost-effective? Seriously, I don't have any significant knowledge on the subject, so I'm just guessing ;)

[Dante]

There are certainly resources beneath the oceans... Just not any we have a hope of reaching. There's enough oil down there to keep us in plastics for centuries, for example. However, the ocean floor is an extremely inhospitable place. Colonisation of it is not currently a viable suggestion, or at least not as viable as a moon base is. And that's saying something...

It might be possible, however, to set up something above the ocean floor. And we're not talking a few metres here, we're talking kilometres. Using a combination of pressurised containers, oxygen and weights and all that, combined with several opposing means of propulsion, it should be possible to keep something more or less stationary on all three axes. It would be difficult to get to of course, and require several hours in a pressurised chamber before and after travelling up or down, and be pointless as a commercial venture... But that's about as close as we'd get for now.

Still, there would be some interesting studies to carry out down there. And who knows? Get a big enough place and it could even provide a kind of lebensraum.

[Dude_Doc]

Still, there would be some interesting studies to carry out down there. And who knows? Get a big enough place and it could even provide a kind of lebensraum.

I doubt it. The risk is already great just with recource gathering, and living there would also carry a great risk. Not to mention that people would have to depressurise if they want to go to another country above water. But well... future will tell...

[Dante]

Did I say it wasn't risky? *shrug* Some enviroments are uncomfortable. People adapt.

[Cyborg]

Not to mention that people would have to depressurise if they want to go to another country above water.

Have you ever heard about submarines?

[Dude_Doc]

Have you ever heard about submarines?

It's not that. If you mean bases in depths of 200 meters or the like, then sure, submarines would work. But what about depths up to one kilometer? You need pressure-chambers. The deeper you go the longer you stay in the chamber. Unless, of course, you figure out another method not currently known to man :) ...

[Cyborg]

Well, Alfa class submarines can (could, as I believe they are discontinued...) dive to 800 - 1 300 metres...

We're not talking about Swedish junk submarines here... :P (Sorry, as a Norwegian, it's my duty to harass your navy.)

[nemafakei]

"Not to mention that people would have to depressurise if they want to go to another country above water."

As opposed to other planets, in which we can roam happily and freely...

[Dude_Doc]

Well, Alfa class submarines can (could, as I believe they are discontinued...) dive to 800 - 1 300 metres...

You still got the pressure-question unsolved. And how would people live down there? It would be a very claustrophobic environment if you want everything to work properly I think...

We're not talking about Swedish junk submarines here...  (Sorry, as a Norwegian, it's my duty to harass your navy.)

Have we submarines?  ;D

As opposed to other planets, in which we can roam happily and freely...

Look, I'm not saying that space is easy to colonize or to travel, my point is that at this time, and in the foreseeable future, it would be easier to colonize space rather than building anything far below the ocean. Some research-station perhaps, with 10 people living in a closed and claustrophobic place for scientific purposes only. But a large scale civilization of thousands of people? No.

[MrFlibble]

I wonder if an orbital space station could accommodate any large number of people ??? Does humanity possess, as of now, means to terraform a planet, at least one of those within our Solar System? If not, then what are the advantages of building colonies on other planet's surface (OK, let's say Moon for a start) than that of building colonies under the sea? Once again, I'm not a specialist and there might be significant technical differences that make space colonization preferable.

[Cyborg]

Some research-station perhaps, with 10 people living in a closed and claustrophobic place for scientific purposes only.

Hmm, do you know what that reminds me of? A space station...

[Dude_Doc]

I wonder if an orbital space station could accommodate any large number of people

That depends. In order to live somewhat normally in an orbital platform we would have to invent artificial gravity, which we don't have yet - but when we have it then it could be possible for such a construction. Right now bases on solid ground is the closest thing we actually can do.

Does humanity possess, as of now, means to terraform a planet, at least one of those within our Solar System?

I believe that we have the means to build bases on our moon and on Mars, the questions and problems that we face right now is the question of sustainability and usefulness. For example, why would we build a base on the moon? What experiments can we do there that we can not do in orbit around earth? What risks are there?

Mars is a problem because of it's distance from us. Last time I heard, it would take a craft 6 months just to go there, and besides that, we must wait a whole year there before we can return, because otherwise we would have to travel a year or longer.

Then we also have other moons around Jupiter and Saturn, but they are too far from the sun to transform.

If not, then what are the advantages of building colonies on other planet's surface (OK, let's say Moon for a start) than that of building colonies under the sea?

For starters, we have "lived" longer in space than we have under water, and I mean weeks, not submarine missions or "underwater restaurants" which aren't even completely underwater. We have more experience in building and launching crafts into space, building orbital platforms, than we have building bases in the ocean. Besides that, it is easier to construct and add construction to bases in space than it is below water, because we haven't done that before - not in the sence of constructing living places.

[Dude_Doc]

Hmm, do you know what that reminds me of? A space station...

And has it been done below water? No.

The reason we don't have wide open spaces in the orbital bases is because we don't have space enough to carry those things into space. The larger the construct, the more money it cost, the more heavier the construct will be, thus requiring bigger spacecraft thus more fuel - thus more harder to carry into space.

And if scientists now are arguing about that we waste money on sending people into space (risk and cost, but few results/nothing new) - then why would they even consider going below water? What experiments can we do below water that we can't do now?

[Tezcatlipoca]

Artificial gravity isn't a difficult thing to achieve. Generally you have two options. An extreamly energy expensive one, and a not so expensive on.

The first works in any environment. As objects move faster, their mass increase, and thus their gravitational pull increases. However, to have any noticable difference for small objects, you have to move them *very* fast. So, imagine a number of ball bearings inside a floor pannel moving close to the speed of light. To get them going that fast, the energy costs would be obnoxious.

The other way is simply to have the station itself spinning. A colony on the moon would have trouble achieving this, but a space station wouldn't. Your "down" would be pointing away from the center of the station. Spin it at a certain speed, and you can emulate the gravity pull you want.

As for space vs ocean, the ocean has extreamly complex ecosystems, even at the "inhospitable" depths. Space, the moon, and other planets in our solar system (as far as we know) have no ecosystems. Knowing our track record at living togeather with other ecosystems, it would be better for non-human species if we took the space route. And seeing how critical the ecology of the ocean is to the atmosphere as a whole it provides more ephmisis on avoiding it any unnecessary damage.

And for getting objects into space, yes, that's the big problem. Keeping them there, and sending them back is cheap. However there are numorous (mostly theoretical) ideas for getting objects into space. The method we use is simply that because we don't want to pour the necessary funds into research. So it's dirty rockets from countries closer to the poles than the equater for all!

[Cyborg]

In order to live somewhat normally in an orbital platform we would have to invent artificial gravity, which we don't have yet

We have that. Rotate your space station, and you have your artificial gravity. (A little too simply put...)

For starters, we have "lived" longer in space than we have under water, and I mean weeks, not submarine missions or "underwater restaurants" which aren't even completely underwater. We have more experience in building and launching crafts into space, building orbital platforms, than we have building bases in the ocean.

How can you say that the crew of submarines don't live underwater? They live just as much underwater as astronauts live in space. It's not too hard to create an underwater base, but we just don't see the use for it. A submarine today can spend months underwater only disrupted by the need of food. If food could be brought to it, it could be stationary for a very long time. What would make that different from a space station?

-------------------

To terraform Mars, we must introduce atmosphere-generating living species there (bacteria? I don't know exactly what they'd use.) I think it's a better plan to terraform Mars before we inhabit it (to have a breathable atmosphere among other things) than to just build a base there.

One thing is to research somewhere. A completely different thing is to inhabit a place because Earth is starting to get over pupulated. I'm not sure which thing we are discussing here... :-

[GUNWOUNDS]

Excellent example with the submarine... it indeed is like a space station.

[MrFlibble]

BTW, I think that subs don't go in too deep not because it is no possible for us to construct such durable hulls, but because huge depths are not suitable for submarines' tasks? Another point is that there are life forms that have adapted to living underwater and sustain enormous pressure, then why don't we do it? It's not the first time humans copied some of Nature's design principles for their tools, vehicles etc.

As for now, building colonies both in space and underwater probably won't seem cost-effective to anyone, but who knows?

[Dude_Doc]

We have that. Rotate your space station, and you have your artificial gravity. (A little too simply put...)

But that is just theory. It hasn't been tested... yet.

How can you say that the crew of submarines don't live underwater? They live just as much underwater as astronauts live in space. It's not too hard to create an underwater base, but we just don't see the use for it. A submarine today can spend months underwater only disrupted by the need of food. If food could be brought to it, it could be stationary for a very long time. What would make that different from a space station?

But we have not been outside of the submarine on a depth of 1000 meters. That is what I am trying to say. Once we're in the submarine we stay there until we surface. But what we are discussing is small-time projects, think of a whole civilization. It would be pointless.

To terraform Mars, we must introduce atmosphere-generating living species there (bacteria? I don't know exactly what they'd use.) I think it's a better plan to terraform Mars before we inhabit it (to have a breathable atmosphere among other things) than to just build a base there.

Well, Mars have heavy winds and unfriendly environment. There will probably be many scientific exoeditions before any terraforming can begin. But in order to get people there and back in as short time as possible, we would have to build a small base there. 

[Cyborg]

But we have not been outside of the submarine on a depth of 1000 meters. That is what I am trying to say. Once we're in the submarine we stay there until we surface. But what we are discussing is small-time projects, think of a whole civilization. It would be pointless.

When you exit a space shuttle in space, you have to wear a suit that's more like a little space shuttle itself than a suit... The same thing would probably be possible to do under water.

[alchemi2]

bio domes have been trial on more than one occasion, cost is always the prohibitive factor, but project are now looking at cheap simpler techs to ac hive bio domes. Can't find the link to the BBC page will have to do some searching.

Basically they were looking at building with moon rock and tunnelling in to surface, then making bio sphere with plants and water. to become self sustaining. initially oxygen and soil would have to be brought in from earth but eventually a viable system could be established or so research had shown.

As ever it always comes down to commercial viability.

[TMA_1]

But that is just theory. It hasn't been tested... yet.

bah, it is more than just a theory. It would definitely work, it just hasent fully been implamented yet.

I dont think mankind will go that far into space. In fact I dont even see it happening in the far future for that matter. The dreams of deep space travel were crushed when the cold war ended. The only thing that might be done is maybe placing experimental colonies on the moon. Other than this, maybe low orbital flight, orbital facilities for scientific testing, and advancements in artificial satellites.

just my opinion though.

[Dude_Doc]

The dreams of deep space travel were crushed when the cold war ended.

I would rather say that the pace of space travel dropped drastically after the cold war, but not that it has ended completely. We just have not found a functional way out in space, or something to find or explore that could answer a bigger question. Right now, Mars is just a big rock in space and travel to Mars will be both risky and expensive, giving us nothing except, of course, the very possibility to go there.

[SpiceGuid]

I agree with TMA, i see space-habitat to remain costly, experimental and limited to the very few.

Otherwise would require a breakthough in both cost, safety and comfort, and what i see is some attempts, promises but little progress.

Some even predict the space-future would be robots-only.