Stairway to heaven

http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2005/09/25/wspace25.xml&sSheet=/portal/2005/09/25/ixportal.html

[BladeRunner]

Good link Homer. I remember a novel written back in 1970
called Ringworld by Larry Niven with similar ideas.
http://www.larryniven.org/reviews/58.htm

[Chacal]

"Fountains of Paradise" is an excellent Clarke novel.

It would be amazing to see what seemed like an impossibly far-fetched idea turned into reality in my lifetime.

[BladeRunner]

Originally posted by Chacal
"Fountains of Paradise" is an excellent Clarke novel.

It would be amazing to see what seemed like an impossibly far-fetched idea turned into reality in my lifetime.

We/me have seen some allready
I was a big fan of si fi novels back in the sixties and seventies.

[Chacal]

Me too. Still have some good ones. I must go and buy Asimov again, this time in English.

[Namloot]

Amazing stuff.

[Gen. Ouch]

too bad thought you guys might be talking about Led Zepplin.

[TChicken]

[i]Fears that an aircraft would crash into the elevator ribbon is just one concern. Space debris and terrorism are others. [/B]

Why the heck did they put this paragraph in there?
Neat idea though.

[cavalierlwt]

One scientist talked about the possibility of a plane hitting the tether (or ribbon). He said as strong as the ribbon was, a jet airliner would be sliced neatly in two and the ribbon would remain intact.

[deathBOB]

Good song.

Anyone read the Red/Green/Blue Mars series? A lot of stuff in those books revolved around control of the space elevator.

bored today and monkeying around with some numbers on this space elevator
earth to space = 62,000 miles
1 mile= 5,280 ft.
62,000miles x 5,280 feet=327,360,000 ft.
(total weight of carbon nanotubes reaching to space station) 62,000 miles x 28 lbs. per mile =1,736,000 lbs. or 868 tons
(cost of nano tubes) $1207 per gram for the purist material
$24.15 for cheapist material
we'l say there going to have to use some pretty good stuff for this carbon nanotube ribbon at a cost of $1000 per gram or $45,000 per lb.(45 grams=aprox 1 lb) source:http://en.wikipedia.org/wiki/Carbon_nanotubes
(total weight of carbon nanotubes reaching to space station) 1,736,000 lbs.x $45,000 = $78,120,000,000


(total weight of carbon nanotubes reaching to space station) 62,000 miles x 28 lbs. per mile =1,736,000 lbs. or 868 tons
(total weight of carbon nanotubes reaching to space station and counterweight) 868 tons + 600 tons (counterweight = 600 tons) = 1468 tons

62,000 miles divided by 365 days (1 year) = 169.86 years (1 mile per day,Sat.,Sun.included)

So, to put things in prespective,
worlds largest oil tanker as of 1999,Jahre Viking fully loaded with crude oil, she has a gross tonnage of 565,000 tons.
average everyday rope (boat rope) 1 foot = 1 ounce (guessing), 16 ft. = 1 lb.
(total weight of boat rope reaching to space station)327,360,000 ft. divided by 16 (16 feet = 1 lbs.) = 20,460,000 lbs or 10,230 tons(2 of those oil tankers)
All that i have to say is they better use some good bolts to anchor the ends with because its going to have the weight of 3 fully loaded oil tankers on each end

[BladeRunner]

Just making a wild guess here but if you could ignore the
effect of air friction, the end attached to the earth does
not need to be attached at all. Centrifugal force from
the space attached end should balance the weight of the
nanotubes.

Naturally occurring spider silk is widely recognised as the strongest, toughest fibre known to man. They should probablly go with this material , its a mixture of goats and spider silk, http://news.bbc.co.uk/1/hi/sci/tech/889951.stm bored today

seems to me,everything structural has some kind of deflection(ever been on big bridge and feel it moving) which is absorbed by its mass, not allowing any ripple affect,where as this thing is going to ripple like the 3-stooges playing a hand saw ,lol, just my guess dont really know what im talking about

[PudriK]

Originally posted by BladeRunner
Just making a wild guess here but if you could ignore the
effect of air friction, the end attached to the earth does
not need to be attached at all. Centrifugal force from
the space attached end should balance the weight of the
nanotubes.

You're thinking's a little off.

From a Space.com article:

For a space elevator to function, a cable with one end attached to the Earth's surface stretches upwards, reaching beyond geosynchronous orbit, at 21,700 miles (35,000-kilometer altitude). After that, simple physics takes charge.

The competing forces of gravity at the lower end and outward centripetal acceleration at the farther end keep the cable under tension. The cable remains stationary over a single position on Earth. This cable, once in position, can be scaled from Earth by mechanical means, right into Earth orbit. An object released at the cable's far end would have sufficient energy to escape from the gravity tug of our home planet and travel to neighboring the moon or to more distant interplanetary targets.

Putting physics aside the toughest challenge has been finding a super-strong cable material. "That's what has kept this idea in science fiction for 40 years," Edwards said. But the right stuff in terms of cable material is no longer thought of as "unobtainium", he said.

The answer is carbon-nanotube-composite ribbon. Small fibers of the material are set down side-by-side, then interconnected to form a growing ribbon.

It actually needs to be attached at the base or it will fly off into space, because the design depends on tension to keep the cable straight. The cable is 62,000 miles long, well over twice the geosynchronous orbit altitude of about 22,000 miles, meaning the center of mass is past the equilibrium point.