Space Elevators - SciFi is becoming RealityNonFi

[Squeak the Rat]

I heard something on National Radio that other day about Space Elevators which was way cool if you're interested in space and exploring etc.

These are structures that go into space so we can lift stuff up and build big spaceships and spacestations etc etc, just like in Space 1999, only a bit later.

The theory goes a little like this: the structure can't be a normal building because it would be too heavy. So it needs to have no weight......

Imagine a ball being swung around on the end of a piece of string. No weight comes down the string, it's all centrifugal forces. Now imagine if the string was realllllly long (about 10,000km), and the ball swung one revolution per day.

Then all you do is get a big laser and a lift with photoelectricthingy cells (like solar panels) to self propel itself skyward and you get payloads to orbit at a fraction of the cost of a shuttle launch and a turnaround of a couple of days.

The theory has been around since the 60's but it's only now that we have the technology. Nasa are running competitions to encourage people and companies to work out the practicalitles and reckon they'll it'll be possible by 2010, ready for 2020.

Believe it or not, all the hard questions have been answered. Check out:
Learn More! (http://www.elevator2010.org/site/primer.html)
Space Elevator Competition (Nasa) (www.elevator2010.org/)
Oh Wiki you're so fine, you're so fine you blow my mind... (http://en.wikipedia.org/wiki/Space_elevator)

Diagram Source: http://en.wikipedia.org/wiki/Image:Space_elevator_structural_diagram.svg

[Steam]

It is indeed cool, but nobody has come up with a tether material yet, even carbon nanotubes aren't strong enough. But eventually we will be in a position to continue avoiding solving poverty, starvation and war, and focus instead on building this. Hooray technology!

I especially like this from the Wiki article: "Some authors (such as science fiction writers David Gerrold in Jumping off the Planet, Kim Stanley Robinson in Red Mars, and Ben Bova in Mercury) have suggested that such a failure would be catastrophic, with the thousands of kilometers of falling cable creating a swath of meteoric destruction along Earth's surface."

[Squeak the Rat]

Did you take my grumpy pill this morning Steam? ;)


What is the current state of Carbon Nanotube Composites (CNTCs) research?
Yearly production of CNTs is increasing each year by a factor of 10. Single Wall Nanotubes (SWNT), which are the type we want, are becoming available in larger and large quantities. CNTCs are maturing very fast indeed. They are now as strong as the strongest materials available commercially, and there isn't a technological barrier to making them as strong as we need them.

[Blackbird]

Arthur C Clarke was a true visionary. I think it was one of his early books where he first suggested the concept.:rockon:

[Steam]

Did you take my grumpy pill this morning Steam? ;)

Grrr! Yes. Arrg! I need to develop anger management skills. Commute home not good.
Cool about the CNT development, it looks like a goer then.
I have some interesting pictures of space elevators in fiction, I'll track them down and post them here later tonight.

EDIT: Here they are, be warned if you are on dialup that the file sizes are from left to right 75kb, 131kb, and 300kb.

[jrandom]

Arthur C Clarke was a true visionary. I think it was one of his early books...

'The Fountains of Paradise', I think.

[Pixie]

But eventually we will be in a position to continue avoiding solving poverty, starvation and war, and focus instead on building this. Hooray technology!



poverty, starvation and war...solve this and the fuckers will just overbreed anyway.
kill 'em all I say

[Winston001]

'The Fountains of Paradise', I think.

Yep, based in Sri Lanka which incidentally is where Clarke has lived for many years.

A space elevator has every prospect of becoming a reality. It needs to be based on the equator to minimise coriolis forces. If it was situated in NZ, then the space end would be swinging around trying to trace our path through space - and it ain't a straight line.

Exciting stuff.

[Steam]

Yep, based in Sri Lanka which incidentally is where Clarke has lived for many years..


EDIT: The following is apparently wrong, thanks to Lias for pointing this out. He may be a right-wing loony but he knows his Clarke-related news.


....based in Sri Lanka which incidentally has no laws against men having sex with minors, notably young boys, which is what Clarke did. THe UK justice system couldn't touch him becasue it was legal there at the time apparently.

He invented the idea of geosynchronous satellites too, and if he had patented the idea, they would have had to give him heaps of money for each launched, he'd be a billionaire right now. He didn't think it worth patenting at the time though.

[Steam]

I heard something on National Radio that other day about Space Elevators which was way cool if you're interested in space and exploring etc.


I have edited my post above, to include dem purrty pictures

[Big Dave]

I posted dem purrty pictures above

So in the third pic why did they put it in a hole?
'Hey! I know how to have to make it a bit longer!'

When Arty got stinky it kinda took the gloss off some of the best sci fi ever for me.
'Rendezvous with Rama', 'The City, the Stars',....sigh.

PS - I also find a future without Armco alarming.

[WRT]

Hang on, sounds like this is a one way ticket. Sure, you can fling stuff outwards, but how does it get back to earth?

I'm thinking, that if there is no way for it to come back down, then we are definitely onto a winner here. Imagine it, we could use nuclear power to solve the worlds energy shortage. Finished with the spent radioactive fuel? No problem, stick it in the elevator and eject it into space!

Murderers and rapists filling our jails? Into the elevator!

Dont want a stinky rubbish dump for your cities? Load the rubbish into containers and into the elevator!

Who needs space exploration? We dont need to leave this planet, all we need to do is eject the bits of it we no longer want. Poverty, starvation, war . . . load the poor, the hungry, and the corrupt leaders (Saddam, George, Bainimarama - oh, and Helen) into the elevator and be gone with them.

[Big Dave]

Hang on, sounds like this is a one way ticket. Sure, you can fling stuff outwards, but how does it get back to earth?



With a thud.

[Big Dave]

EDIT: Here they are, be warned if you are on dialup that the file sizes are from left to right 75kb, 131kb, and 300kb.

It could be worse - you could be on Ihug.
Do people still do dial up?

[Blackbird]

[QUOTE=Big Dave;859520]
'Rendezvous with Rama', 'The City, the Stars',....sigh.QUOTE]
Clarke is one of the few authors with the ability to make the hairs on my neck stand up with his phraseology. The Rama series painted an incredibly clear visual picture. One of his early books, Childhood's End, is a personal favourite and his explanation of why the Devil's classic horns, forked tail and wings entered mythology is an absolute beaut.

[Steam]

Do people still do dial up?

63% of connections in NZ are still dialup, amazing eh!

[Steam]

Hang on, sounds like this is a one way ticket. Sure, you can fling stuff outwards, but how does it get back to earth?


It's an elevator, so the most practical idea is that it has a counterweight, so some stuff goes up and some goes back down to earth.

Otherwise it's going to take exactly the same amount of energy as a shuttle launch to get a payload into orbit.

[WRT]

Still think my idea of using it as an ejector chute is better . . .

[Winston001]

Hang on, sounds like this is a one way ticket. Sure, you can fling stuff outwards, but how does it get back to earth?



As a shuttle/lift cage goes up, a counterbalancing one goes down. This isn't necessary for every design however but the beauty is that it is a free ride.

Essentially the lift/tether is hundreds of kilometers long, ending at a station where the forces of gravity are balanced against the centrifugal force of the spinning Earth. The length stops the elevator from whipping around.

Back down the lift there would be a main station, about 50km above the planet (from memory) where payloads would be delivered. This is where rockets would arrive and depart from with people and equipment. The big benefit of the elevator is that it is an energy neutral way to get into space. Once you are out of Earths gravity well, you can move around quite easily.

[WRT]

Seriously, you guys are all missing the point . . . imagine strapping Helen into a chair for the ride of his life, and knowing there is no way he could ever come back!

[Lias]

....based in Sri Lanka which incidentally has no laws against men having sex with minors, notably young boys, which is what Clarke did. THe UK justice system couldn't touch him becasue it was legal there at the time apparently.
It was an allegation made in 1998 by The Sun (Which is a piece of sensationalist tabloid shite and should hardly be considered a canonical trustworthy source for news), and the allgeations were in the end proven to be false AFAIK.

[Motu]

the allgeations were in the end proven to be false.

Aaaagh! I just burned all my Arthur C Clarke books,and now you tell me! No one mention Asimov please....

[Ixion]

You're going to turn this into another denunciation of sucky hover things, aren't you.

[WRT]

I thought hover things were blowy rather than sucky? Although I guess that's all just a matter of perception, and whether you are standing above or below it.

[Motu]

The correct designation is sucky blowy,however the diminutive of sucky is acceptable in certain circumstances.

I read a book recently where the space elevator came down leaving a path of destruction - is that one of the previously mentioned?

[Squeak the Rat]

Nah, it only weighs 1kg per kilometer of cable. Anything above 2500km would burn up on renentry so it would just be a big long light cable around the equator.....

I thought there was no such force as sucky, just a displacement of pressure caused by a blowy......

[WRT]

I know I displace a fair bit when subjected to a blowy . . .

[badlieutenant]

'The Fountains of Paradise', I think.
thanks fish, couldnt remeber the name of it.

[Motu]

No,you have to have the suck before you can blow - if you blow before the suck it's called something else.

[McJim]

So THAT'S how them ol' Indian fellas got their ropes to stand on end.

glad we sorted that out then.

[Winston001]

"Suck Mary-Beth Suck!! Blow is just a figure of speech!!!"

[Winston001]

Right, now we have that out of the way, thanks for the topic Squeak. The Wikipedia site is pretty good and has grown since I last read it.

There are all sorts of interesting science projects which we have the capacity but not the political will to explore. Fusion reactors, anti-matter, and space elevators are but 3 examples.

Jerry Pournelle told the US Congress in the 1970s that if they took the money from nuclear weapons development and devoted it to fusion power, we'd have working reactors today. Pournelle is a visionary scientist and Sc-fi author whose writings about the edges of scientific discovery are well worth reading.

[Pixie]

Essentially the lift/tether is hundreds of kilometers long,



Try 50,000 km plus long
The center of mass of the entire cable / terminus /counterweight system is in a geosynchronous orbit,which has to be 42245 km from the earth.
The actual counterweight itself is further out,at a distance that is dependent on what size asteroid that can be captured and manoeuvred into orbit

[Pixie]

It's an elevator, so the most practical idea is that it has a counterweight, so some stuff goes up and some goes back down to earth.


The systems in design at the moment don't use a counter weight like a elevator in a building.That would require 84490 km of cable.


Otherwise it's going to take exactly the same amount of energy as a shuttle launch to get a payload into orbit.

less the energy needed to lift the weight of the space shuttle and fuel