Going up? Space elevator wins support U.S. company builds on Russian idea

National Post ^ | 8/13/02 | Dan Rowe

[Libertarianize the GOP]

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[RossA]

Careful here! In one of Larry Niven's stories the elevator breaks. At least 22,000 miles of it (all of it below geosynchronous orbit) - and maybe more - would fall and wrap itself around the equator - almost exactly once. (I'm pretty sure it's a coincidence that the geosynchrous orbit radius is close to earth's diameter).

I wouldn't want to be living near the equator if it broke.

[Quix]

bump for files

[Husker24]

I have a feeling that this is one of those things that works out better on paper than in real life.

[unixfox]

NASA THE AMERICAN TAXPAYERS have given HighLift a US$570,000 grant to continue research...

[tictoc]

HELP WANTED

MUST HAVE A GOOD HEAD FOR HEIGHTS

NOW ACCEPTING APPLICATIONS

[Brett66]

Kim Stanley Robinson must have stole that idea from him, in Red Mars the Martian elevator falls due to a terrorist attack. It was like a meteor impact, except it encircled Mars' equator.

[RightWhale]

is the design any good? 1 meter wide and paper thin is fine at each end. Something doesn't add up. What is the tensile strength of carbon nanotubes compared to ordinary spiderweb?

[Consort]

As the load gets higher, the centripetal force will rip the anchor out of its mooring.

[Saturnalia]

As stated in the article, they are shooting for 30 times the tensile strength of steel.

[cinFLA]

As the load gets higher, the centripetal force will rip the anchor out of its mooring

Check your physics textbook or at least a dictionary.

[RightWhale]

That won't do it. The band might be 1 meter wide and paper thin at each end, but it will have to be amazingly thick in the middle. The space elevator has been discussed several times on FR over the years. It is impossible at all with steel. It is barely possible with carbon fiber. Maybe carbon nanotube or spider web is better, but it won't allow a thin sheet of material all the way up. Also, with the stated load limits of this one elevator, several more elevators would be needed around the world. There will be a lot of carbon mass in these structures.

[Brett66]

The figures I get for this stuff is that a single perfect nanotube is about 10 to 100 times stronger than steel per unit weight. Amazing stuff, it still costs more than gold to produce, but we have the materials to build such an elevator. The good thing is that a lot of auto manufacturers are drooling over this material, I believe they'll find a way to bring the costs down to make such a project economically feasible.

[RightWhale]

centripetal force will rip the anchor out of its mooring

That wouldn't be the failure mode. The cable might snap in the middle, but it is balanced overall. A Boy Scout tentpeg could hold it down on the ground until the thing starts whipping around due to other factors.

[RightWhale]

centripetal force will rip the anchor out of its mooring

That wouldn't be the failure mode. The cable might snap in the middle, but it is balanced overall. A Boy Scout tentpeg could hold it down on the ground until the thing starts whipping around due to other factors.

[Brett66]

A single perfect nanotube is about 10 to 100 times stronger than steel per unit weight. Unfortunately it costs more than it's weight in gold to produce. The auto manufacturers are very interested in this material, I believe they'll find a way to bring those costs down rapidly.

[RightWhale]

10 to 100 times stronger than steel per unit weight

I don't have that old Analog Sci-Fi magazine around anymore, but in there they estimated the cable would have to be a kilometer thick at the main stresspoint. I think it was carbon fiber construction.

That's a lot of carbon.

[Brett66]

I posted the first time and my post didn't show up even after refreshing, I thought the post was lost and then I made a second response and it shows up? This server is possesed sometimes.

[billybudd]

I'm skeptical on how these nanotubes, even at 100 times stronger than steel, will be able to compensate for the extreme forces at work here.