# Re: shuttle disaster (space elevators)

```Ray wrote:

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```On Thursday 06 February 2003 11:55, John Hasler wrote:
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```Mike M writes:
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```Can you imagine a 100 or a 1000 of these things?
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```Yes, but why would you need that many?
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how many different airports do we have now? seems like 1000 would be normal to low.
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```Would it be possible to use them to increase the length of a day?
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```The question makes no sense.
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yes it would be possible to slow the rotation of the earth, but it would take a bit of work to do using these before it became noteable (unless you have your days down to 12 digits)
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```What would happen when the ribbon broke and came fluttering back to the
planet's surface?
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```It would break at the weakest point which would be at the bottom.  The
ribbon would not be under tension so it would pretty much just hang there
waiting to be repaired.
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it actually depends on how its done, most likely the tension which it would have would pull it away from earth (atleast the part still attached to the far end) and if it broke off high enough, then yes, there would be a line of ribbon that comes down that could cause problems.
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one of the many questions i can't answer is
Why is this thead still going? and why on Debian User?

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It is not hard to compute the tension in a space elevator ribbon. (It would be a fair question for a final exam in an undergraduate mechanics course.) It depends on position along the ribbon, on the Earth parameters (size, rate of rotation, etc. ) and on the mass-per-unit-length (kg/m) that is assumed for the ribbon. The ribbon must be at least thick enough to be strong enough to keep from breaking under its own self-generated tension. The last time I checked, there was not a material having a suitable combintation of kg/m and tensile strength.
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