very interesting NASA space elevator study

My apologies, looks like I was wrong, Mr. Edwards is claiming that
current materials work; and has that picture of a 3cm length!

Wow.

Still, he doesn't include any tensile strengths or anything, so I
am wondering if there's been a mistake somewhere. Who's fiber is this?

Ian Woollard wrote:

> Al Globus wrote:
>
>> What Edwards paper does is show use that existing materials can,
>> plausibly, build the elevator.
>
> If so, I've missed the news. AFAIK it's not yet possible to build, say a
> foot long length of the required strength, or even a 1 mm length; and
> 38000km is a bit more than that.
>
> (Actually I think CVD polycrystalline diamond might theoretically be
> made to do this too, but hasn't reached practical cost or production
> rate points, and its properties are difficult for this application as
> well; it atleast is being made in the cm size regime, rather than nm
> size like nanotubes.)
>
> And I dimly recall reading an article in New Scientist that says that
> macroscopic nanotubes weren't nearly as strong as hoped, in practice.
> I'm not sure they knew why; materials science is difficult. I'm hoping
> they can fix it; but it's anyone's guess when.
>

--
- Ian Woollard (ian.woollard@...)

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