The Space Elevator Comes Closer to Reality

Ian Woollard wrote,

"A fiber with a tensile of 73 Gpa exists; the required strength
is 72.5 Gpa. However, a) we need a safety factor b) we need to
be able to splice the fibers together, and in practice that
loses 15-30% of the strength."

What is the required strength for a space elevator from the Lunar surface
to lunar orbit?
Do currently-existing materials suffice to build such a lunar elevator?
Would a lunar elevator be a simpler technological solution to the problem
of moving large amounts of material off the moon than the O'Neill-heritage
mass driver/mass catcher system?

Ron Menich
********************

Ian Woollard
03/28/02 07:24 PM
Please respond to spacesettlers

To: spacesettlers@yahoogroups.com
cc: webmind@yahoogroups.com
Subject: Re: [spacesettlers] Re: [Webmind-TLC] Fw: The Space Elevator Comes Closer
to Reality

Lucio de Souza Coelho wrote:

> This new proposal for a space elevator is most interesting, for in the
> beginning you would just have to launch a geostationary satellite with
20
> tones of carbon nanotube thread (and 20 tones is perfectly achievable
with
> current rocket technology). The tip of the thread is dropped back to
Earth
> and then you extend a lot of new threads climbing the first one. In the
end
> you have a thick cable able to hold an space elevator weighting tens of
> tones going back and forth Earth surface and GEO.

Yeah. The only problem is the tether- nobody can actually build
a tether right now with the required strength.

A fiber with a tensile of 73 Gpa exists; the required strength
is 72.5 Gpa. However, a) we need a safety factor b) we need to
be able to splice the fibers together, and in practice that
loses 15-30% of the strength.

> That is FAR more feasible than all the space elevators proposals found
in
> science fiction, were people put a carbonaceous asteroid in orbit and
then
> start building the elevator with the asteroidal materials.
Unfortunately,
> that is a chicken-and-egg problem: you cannot move an entire asteroid to
get
> easy access to space because we don't have easy access to space. This
clever
> solution of the cable 100% "made in Earth" may finally allow the chick
to
> leave the egg.

Sure. He's solved all of the problems except one: WE NEED A
CABLE!

> Lucio Coelho
>
> From: "Anton Kolonin"
> To:
> Sent: Thursday, March 28, 2002 9:08 AM
> Subject: [Webmind-TLC] Fw: The Space Elevator Comes Closer to Reality
>
>>>ALBUQUERQUE, NEW MEXICO -- Make way for the ultimate high-rise project:
>>>the space elevator. Long viewed as science fiction "imagineering",
>>>researchers are gathering momentum in their pursuit to propel this
>>>uplifting concept into actuality.
>>>
>>>For the rest of this article, see
>>>http://www.space.com/businesstechnology/technology/space_elevator_020327
>>>-1.html
--
- Ian Woollard (ian.woollard@...)

"Is a planetary surface the right place for an expanding
technological civilization?"
- Gerard O'Neill