In article ,
Dr. O dr.o@xxxxx wrote:
In order to clear the earth, you need to jump off at around half-way up
(rough BOTE).

Halfway to GEO? That's 15.000km upwards! Why do you need to go up that far?

Because until you're at least a few thousand kilometers up (it's not quite
as bad as the BOTE numbers suggest), if you jump off, the orbit you're in
intersects the atmosphere.

(And until you're considerably higher up, it intersects the inner Van Allen
belt, making it an unhealthy choice.)

You can just use a rocket to push you into LEO, you're already going
15.000km/hr (motion of the Earth)...

Uh, no, Earth's equatorial motion is only about 1600km/hr. The elevator
gets you clear of the atmosphere, which is nice, but otherwise it isn't a
lot of help for getting into LEO.

Mind you, an operational space elevator makes LEO a somewhat less
interesting place -- in particular, it's no longer the logical place for
an assembly/operations base for things going farther out.
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