Space Elevator in 15 years?

[KrazyHorse]

KH - I dont belive you took into account the Thickness (mass per unit of length) of the Cable above Geosyncronus Orbit.

Yes I did.

[KrazyHorse]

Also you must take into account that every part of the Cable is a differnt distance from the Earth and thus its weight is differnt.

Duh.

How much training do you have in physics, beautiful?

[KrazyHorse]

I'll give you a couple of hints:

GM/(r^2) is the acceleration due to gravity at any distance from a spherical mass

- r*w^2 is the fictitious acceleration provided by the fact that the rotating frame is noninertial

[KrazyHorse]

And as for not taking into account effects of mass above geosynchronous:

Now to get the total force on the the cable we integrate from R0 to Rf

This integral is not limited by Rg the radius of geosynchronous orbit. It's limited by the unknown Rf which I solved for by assuming a balancing of net force.

[KrazyHorse]

Originally posted by Urban Ranger


I don't think it's efficient to use a Space Elevator to put things into geosynchronous orbit. Wastes too much energy. Much better just move a rocket into low orbit and fire it from there.

?

This makes no sense.

I have the feeling you don't understand how this thing works.

[Dis]

Yeah, the hard part is getting into orbit at all.

Although the power source I'm still concerned about. To get up in orbit they want to beam a laser onto a solar panel on the underside. This technology is proven. But clouds and other debris could cause problems. And imagine the poor bird that flies through the laser . And I believe they have solar panels on the top as well. This would be used for the higher stages.

[Cruddy]

Originally posted by KrazyHorse
I'll give you a couple of hints:

GM/(r^2) is the acceleration due to gravity at any distance from a spherical mass

- r*w^2 is the fictitious acceleration provided by the fact that the rotating frame is noninertial

AH! So these cables are attached to a rotating frame? Presumably circular with a radius of 60,000 miles or so?

Yep, definitely pie in the sky.

[Dis]

The earth is the rotating frame

[KrazyHorse]

Originally posted by Cruddy


AH! So these cables are attached to a rotating frame? Presumably circular with a radius of 60,000 miles or so?

Yep, definitely pie in the sky.

frame = frame of reference

i.e. not a physical construct

[Lancer]

Out behind the Philippine house, past the banana farm, pretty close to the equator, we own a small lot that isn't being used. I suggest we start the space elevator there in September.

There is a Sari Sari store with cold beer which would be useful for the extensive planning needed.

Are you with me?

[DanS]

This is a cool exercise, but this scientist is genuinely off his rocker if he thinks it will be done in 15 years at a cost of $10 billion.

For one, buckytube rope has just recently been fabricated and it doesn't yet come anywhere near the required strength. Further, this stuff is insanely expensive right now. $500 per gram in really short tubes.

It seems to me that very high towers and skyscrapers will be built with the stuff before people are able to wrap their heads around space elevators. Buckytubes are much stiffer than steel, so people wouldn't get sick on 459th floor from swaying in the wind.

[Dis]

can it handle a plane crash into it?

[The Mad Monk]

Depends.

[Impaler[WrG]]

I dont think this material will be very usefull for conventional Buildings. Its got great TENSILE strength but as far as I know little or no COMPRESSIVE strength. Steel and Concreete will still be the best materials for compressive strength. The first aplications will be in replacing steel cables in Bridges or cranes, the elimination of Rust will be icing on the cake.


As for a plance Crash (asuming you ment lateraly into a piece of taut cable) would be a test of shear strength which I dont realy know about. Potentialy the plane might be sliced in half like cutting cheese with a wire or the cable might stretch for hundreds of miles. Or the plane would explode on impact and the fire ball would likly cosume and burn the carbon in the cable.

[:) Smiley]

Page 14 from Cornerstone