My barista's '90s UVA English prof taught TRP at Cornell

[Mark Kohut]

M.H. Abrams. Although I don't find any UVA connection

--- On Sat, 9/19/09, David Kipen <kipend at arts.gov> wrote:

> From: David Kipen <kipend at arts.gov>
> Subject: My barista's '90s UVA English prof taught TRP at Cornell
> To: "'pynchon-l at waste.org'" <pynchon-l at waste.org>
> Date: Saturday, September 19, 2009, 7:21 AM
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> Any guesses? She thinks the name might've been Allen or
> Alden...
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> From: owner-pynchon-l at waste.org
> <owner-pynchon-l at waste.org>

> To: 'tbeshear'
> <tbeshear at insightbb.com>; 'Daniel Cape'
> <daniel.cape at gmail.com>; kelber at mindspring.com
> <kelber at mindspring.com>; 'pynchon-l'
> <pynchon-l at waste.org>

> Sent: Sat Sep 19 04:46:40 2009
> Subject: RE: NP Mars Trilogy

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> Tbeshear
> sez: 
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> Clarke
> introduced the
> idea of the space elevator in The Fountains of Paradise.
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> Konstantin Tsiolkovski published the idea
> of a “space
> tower” in 1895. He knew it was un-buildable,
> _gedanken_, but his
> point was the conceptual physics: IF it could be built, you
> could climb it at a
> comfortable pace, on foot or by elevator or whatever,
> acquiring a little bit more
> transverse velocity at each step as the tower swung around
> with the earth’s
> rotation, until at about 23,000 miles you’d be moving at
> orbital velocity
> and could step off and float. (23,000 miles is
> geosynchronous orbit, in which a
> satellite stays over the same point on the equator.
> Tsiolkovski seems to have
> been the first to grasp that, too, as Clarke knew and
> acknowledged whenever people
> tried to credit him with it.)  
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> In 1960, Yuri Artsutanov went most of the
> remaining conceptual distance
> by replacing the tower with a cable in tension. A
>  mass beyond geosync orbit –
> where it would revolve *faster* than orbital
> velocity for its altitude,
> and pull up/outward – would counterbalance the weight of
> the cable from
> orbit down to earth’s surface. Much more feasible, as the
> cable doesn’t
> buckle the way a tower would at even a small fraction of
> 23,000 miles, and many
> engineering materials are stronger in tension than
> compression (cf. suspension
> bridges). Artsutanov also had the crucial insight that you
> didn’t have to
> do the full- size cable all at once, but could begin with a
> lighter fiber just
> strong enough to support itself, and then use travelers to
> “spin”
> additional fibers, as we build up the main cables of
> suspension bridges. 
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> Although the counterweight remained in most
> SF versions (“start
> by maneuvering an asteroid into geosync or Mars-synchronous
> orbit”), it isn’t
> essential: the farther the cable itself extends beyond
> geosync orbit, the less
> mass you need at the far end. And if you can do a
> 23,000-mile cable in the
> first place, it’s probably easier to just do a longer one
> than to go
> asteroid-wrangling. 
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> All this was much less fantastic than the
> original space tower,
> but still out of reach. Artsutanov had been thinking of the
> graphite “whiskers”
> discovered in the late 1950s, with the highest
> strength/weight known, but still
> not good enough. Steel, even diamond were right out: even
> tapering both ways
> from geosync orbit, they’d have to be impossibly thick
> and mass  millions
> or billions of tons. If you have the tech to put that much
> mass into space, you
> don’t NEED a space elevator. 
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> The most recent step was the discovery c.
> 1990 of carbon
> nanotubes, stronger than graphite whiskers. (Mentioned in
> _Green Mars_
> as handwaving, without detail.) They *might* just be
> strong/light enough
> to do the job (still some uncertainty about basic
> measurements) if they could
> be made flawless enough  and bonded to each other on
> an adequate scale. In principle,
> a thousand tons or so could do the job. That’s what got
> the space
> elevator conferences going in 2002, and disseminated the
> idea that we’re
> ready to go. In fact, there’s a LOT of basic research
> still to do on
> growing carbon nanotubes, and a LOT of process engineering
> not even begun on
> turning them into reliable bulk material, It could easily
> take as much R&D investment
> and time as there was between the first transistor c. 1949
> and an Intel
> multi-core CPU today. Space elevators are a seriously cool
> idea to get around
> the inexorable limits of rocketry (also perceived by
> Tsiolkovski back in the
> day), but if they happen it won’t be soon.  
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