Re: space elevator

["Technician" <technician@xxxxxxxxxxxx>]

Oh dear. A space elevator. By chance did this idea spring from the current
NASA plans to actually try to do this in real life?

NASA is currently looking at this idea as a means to reduce the cost of
sending up supplies and crews to the ISS.

There are alot of members in the Anomalies communities BBS that are split on
this idea with NASA. Some say its too risky, such a long cable and too many
variables, others believe its a viable idea and safe.

Sounds fun, but Ill stick to my Centurion craft and not be tied by a rope to
mother Earth. :)


-----Original Message-----
From: David Henderson <orbiter@aibs.org.uk>
To: orbiter@firedrake.org <orbiter@firedrake.org>
Date: Wednesday, December 18, 2002 10:20 AM
Subject: Re: space elevator


>On Wed, 18 Dec 2002, DarkDAVE wrote:
>
>> what about point number 5? u didnt comment on that, the idea of using
mesh
>> objects to act as chunks of 3d landscapes for individual sections of the
>> planet sphere. Surely colision detection could be done for those objects?
>> given that their smaller than the planet themselves.
>
>I'm afriad that's not my area of expertise, so I didn't think a comment
>useful.
>
>> Regarding the space elevator, im not sure where youre coming from with
your
>> pesimism, are you saying it's not practical to SIMULATE it in orbiter? or
>> are you saying it's not practical do implement it in real life?
>
>Not a practical proposition in general. I've seen no realistic description
>of dimensions and how you combat gravity.
>
>> There has been extensive research done on the space elevator, and all the
>> experts to my knowlege has agreed it's possible and withing man's reach.
>> Only thing in dispute is the time frame to build it.
>
>These are fantasy at best and corruption at worst. I'm not a member of the
>yahoo group so those links don't work, but can you cite any credible paper
>published in a peer-reviewed scientific journal?
>
>I'll explain where I'm coming from:
>
>In order to have a fixed point on the earth extending into oblivion, the
>roational period of the far point must be 24 hours. No problem, the
>adverts say, we put an asteroid in geosync. An *asteroid*?
>
>Let's imagine, for example, the asteroid is indeed in geosync. We then
>attach a (very heavy) cable to it. That cable isn't in geosync, so it
>exerts a drag force on both the earth, and your asteroid. Most likely
>result: broken cable, other likely result: asteroid now in decaying orbit.
>
>No problem they say, we'll keep the cable permanently in tension by
>cunningly moving the asteroid out and using the cable to accelerate it
>inwards at the required rate. Now you're proposing to accelerate an
>asteroid at, say, one metre per second ad infinitum. What happens when
>there's a break? Oops, lost the asteroid.
>
>Next problem: what good does this geosync rope do you? Can you climb up it
>as they say? No. Of course not. You're exterting that force on the anchor
>at the far end. That anchor now can no longer be an asteroid, it must be a
>rocket that pulls back at the same force you extert. Energy saving over
>putting the satellite on a rocket: nil.
>
>What about low earth orbit? You can't just jump off at 200km, as you'll
>fall straight back down. You need to achieve orbital velocity. What's the
>proportion of a rocket that lifts the satellite to 200km relative to the
>proportion that accelerates it to orbital velocity at 200km? Plus this
>cannot be done instantaneously, so you're still carrying fuel for lift
>work as well.
>
>All things considered, I just don't see how it can possibly work.
>
>--
>yours etc.                                             [gin.aibs.org.uk]
>                                               Mobile:      07960 217459
>David.                             Work (Direct/Vmail): 020 8898 6565x38
>d.henderson.96@cantab.net          Work (Main):            020 8893 3884
>
>
>
>
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