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You have to freaking put the station into orbit though dontcha boy.

How much has the station we ahve up there cost so far, a Trillion? Thats massive bucks. For what? zinc? Who gives a fig? What costs bucks resource wise is not in space.

There's no wire strong enough to handle the amount of force that is being exerted upon the wire from the centrifugal force. The Earth rotates at 465.1 m/s. A wire that is 200 kilometers long supporting another end would running at exponentially higher speed. The centrifugal force on the wire would be the weight of the wire, any drag though the atmosphere and the attached object on the other end. So, in effect no object made currently can withstand the force without snapping. On top of that the friction from the rotation would heat up the wire and weaken it's material structure.

It's a great concept but no real world material to support it.

SilverMK2 wrote:Well, for one there are greater concentrations of rare materials in space, or so it is suggested, than in the Earth. And whilst you may have to mine 1,000's of tonnes of rock to get a few tonnes of it on Earth, you might have to mine a lot less to get far more in a metallic asteroid.

And it is relatively cheap to shunt asteroids, you don't even need to send a manned ship. Send an ion rocket out there, dock it to the asteroid and motor on home.

Relatively cheap? Relative to what? Not to mining things from the Earth.

I don't know what super rare materials we'll be after that only exist in asteroids. Iron? Nickle? Rock?

The rock itself tends to protect from radiation. I think 1m of packed earth reduces radiation exposure by around 50%, with each subsequent metre further reducing exposure by an 50%. So by leaving a couple of metres of rock between you and the outside world, as well as coating any habitation inside the asteroid with additional protective layers should provide all the radiation screen you require.

Gravity can be simulated by spinning up the rock.

Air, water and food can be a problem but with advances in hydroponics, water recycling, etc you can certainly mitigate the problem. The ISS does pretty well for itself, and with potentially a mile or so diameter rock to play with, you have plenty of space to grow plants, create lakes, etc...

And if you build a city underwater you don't have to worry about radiation, you can desalinate your water supply, you can have artificial air and lighting... how is this asteroid better than the most inhospitable places on Earth?

Well, bunkers will not prepare us for when the sun goes into its final stages and wipes out all life in the solar system.

They easily could, with a billion years of advancements.

It's impossible to predict anything about humanity in a billion years. We won't exist in any sort of recognizable fashion. There needs to be a better example of a disaster than that.

Who knows what things further research could produce in zero-g?

And with the way things are going, we will need more and more of these specialist materials, leading to an increased requirement for space stations etc. Plus, with an increase in production capacity, there will be a decrease in price, leading to more people being able to use the material, so an increase in demand... the circle of capitalism.

So these things will be in huge demand... but you have no idea what they are, because they haven't been invented yet?

What even uses zero-g manufactuing? I've heard it suggested for a few specialist electronic parts but that's about it.

We need them now damn it!

They'll be able to give everyone six boobs like a daemonette. Hold your horses!

Frazzled wrote:You have to freaking put the station into orbit though dontcha boy.

How much has the station we ahve up there cost so far, a Trillion? Thats massive bucks. For what? zinc? Who gives a fig? What costs bucks resource wise is not in space.

Sure, but after that your golden. Will pay for itself after a few trips.

inquisitor_bob wrote:There's no wire strong enough to handle the amount of force that is being exerted upon the wire from the centrifugal force. The Earth rotates at 465.1 m/s. A wire that is 200 kilometers long supporting another end would running at exponentially higher speed. The centrifugal force on the wire would be the weight of the wire, any drag though the atmosphere and the attached object on the other end. So, in effect no object made currently can withstand the force without snapping. On top of that the friction from the rotation would heat up the wire and weaken it's material structure.

It's a great concept but no real world material to support it.

For one thing, you're thinking of centripetal force not "centrifugal force." For another, it is completely possible. Hence why NASA have poured billions into the idea.

whatwhat wrote: For another, it is completely possible. Hence why NASA have poured billions into the idea.

Its possible, but not with current materials. Carbon nanotubes offer a compelling direction for research, but we don't know how to bind them in a way which will allow for the creation of anything like a cable or ribbon tether (not yet, anyway).

Also, the NASA hasn't spent anything close to a billion dollars on the space elevator (their annual budget is only 17 billion). They've given out around 4 million in prizes to freelance engineers, and 35 million in funding to the NIAC, but that's about it.


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Frazzled wrote:
How much has the station we ahve up there cost so far, a Trillion?

Total cost over the lifetime of the station is expected to be around 100 billion euros/dollars; depending on the agency doing the reporting. Space exploration is actually cheaper than most people think, though its certainly not cheap enough to make a viable source of material resources. Unless of course we find an asteroid composed entirely of diamond, gold, and platinum.

We need to break the light speed barrier. Then we'd be in business.

Or we'd find ourselves at the hands of thirsting gods formed from our darkest sins.

dogma wrote:Unless of course we find an asteroid composed entirely of diamond, gold, and platinum.

Diamonds are actually spectacularly common, they are just kept expensive for retail. Had a Geology professor that used to go on about it. Let's get some emeralds!

Orkeosaurus wrote:Or we'd find ourselves at the hands of thirsting gods formed from our darkest sins.

Work your cards right now and you don't even have to leave Earth for that.

Orkeosaurus wrote:Relatively cheap? Relative to what? Not to mining things from the Earth.

I don't know what super rare materials we'll be after that only exist in asteroids. Iron? Nickle? Rock?

Well, relatively cheap compared to building your own space station. You pick an asteroid with a high metal content, send a motor ship over, fly it back to orbit then perhaps land a small team on it to set up some automated drills and manufacturing components and go back home.

Leave it for a while drilling and refining some ore and producing some basic habitat components, then come back up, assemble some shelters etc in the now cleared sections of the asteroid, and go on from there.

You can then use a space elevator or other tech to drop any spare refined metal or ore down to the surface if you want/need to.

And if you build a city underwater you don't have to worry about radiation, you can desalinate your water supply, you can have artificial air and lighting... how is this asteroid better than the most inhospitable places on Earth?

Sure, I am not denying that you will face problems, but then again, you will never have to deal with earthquakes, salt water corrosion, tidal waves, etc. Plus asteroids can be used as the space anchor for space elevators, which are good things

They easily could, with a billion years of advancements.

It's impossible to predict anything about humanity in a billion years. We won't exist in any sort of recognizable fashion. There needs to be a better example of a disaster than that.

Of course

I was just giving the most dramatic example.

So these things will be in huge demand... but you have no idea what they are, because they haven't been invented yet?

What even uses zero-g manufactuing? I've heard it suggested for a few specialist electronic parts but that's about it.[/quote

I could not tell you off the top of my head, but then that is probably because the quantity of manufacture is so small at the moment that they are not really in use outside of specialist labs etc.

They'll be able to give everyone six boobs like a daemonette. Hold your horses!

Woo!

SilverMK2 wrote:Well, relatively cheap compared to building your own space station. You pick an asteroid with a high metal content, send a motor ship over, fly it back to orbit then perhaps land a small team on it to set up some automated drills and manufacturing components and go back home.

Leave it for a while drilling and refining some ore and producing some basic habitat components, then come back up, assemble some shelters etc in the now cleared sections of the asteroid, and go on from there.

You can then use a space elevator or other tech to drop any spare refined metal or ore down to the surface if you want/need to.

All of these automated processes are quite a bit beyond our current technological ability.

I don't know if putting asteroids into orbit will ever be cheaper than building space stations (I sort of doubt it, honestly), but they for sure won't be unless they're huge and being brought in en mass, and I still don't know why we would need to have that many gigantic space stations (asteroid or conventional) in operation.

Sure, I am not denying that you will face problems, but then again, you will never have to deal with earthquakes, salt water corrosion, tidal waves, etc. Plus asteroids can be used as the space anchor for space elevators, which are good things

But you will have to deal with solar flares, high speed debris, collision with other satellites, and more.

But in any case, building a city under water is a terrible idea. Building more skyscrapers is better, building cities underground is better, building cities in the Sahara is better, building cities of ships is better, building cities in Siberia is better, building cities into mountains is better...

And space elevators are only as useful as going into space is. Building space elevators to go build more space elevators obviously isn't going to make sense.

Of course

I was just giving the most dramatic example.

But the only other one I can think of is "ridiculously huge asteroid that would actually, physically destroy the planet", and I don't think those are particularly common. And we could probably set up defenses against them, which would do a lot more for the human race than having a small colony to try and carry on with our species after the destruction of our homeworld.

I could not tell you off the top of my head, but then that is probably because the quantity of manufacture is so small at the moment that they are not really in use outside of specialist labs etc.

If you don't know what they are, what are the chances they'll suddenly become incredibly popular?

Just because there's a small supply of them doesn't mean there's not also a small demand for them. Additionally, this is all stuff that can be done in orbit; and let's face it, we're already there. We have billions of dollars worth of hardware floating around there already, contributing immensely to our daily lives. Even if we do increase the presence in our own orbit significantly, we're not really expanding by a huge degree (and I do think that we're going to be doing more in orbit in the future; I just don't see the need to migrate past that until we can break light. Except for some exploration work, maybe to investigate the possibility of life in our own system, which seems unlikely but would be a huge discovery).

whatwhat wrote:
For one thing, you're thinking of centripetal force not "centrifugal force." For another, it is completely possible. Hence why NASA have poured billions into the idea.

You're quite correct it's the Centripetal force. No, NASA hasn't put billions of dollars into a space elevator.