[ RadSafe ] space elevator

[Brennan, Mike (DOH)]

I've been following Liftport, one of the leaders in the space elevator quest for some time, and it is a very interesting proposition.  We now have materials that could be used for a Moon-to-space elevator, though we do not have materials that can be used for an Earth-to-space elevator (but there is good reason to believe we will be there soon).

The Earth-to-space elevator proposed by Liftport would have a station in geosynchronous orbit (about 42,000 km), with a ribbon continuing out another 90,000 km (give or take) to act as a counterbalance.  Cars climbing the ribbon from the ground would take one to two weeks to reach the station (cars going to Low Earth Orbit to release satellites would get there in a couple of days).  The counter balance ribbon could be used as a launch system, letting probes free-wheel down the ribbon, using centrifugal force to sling (literally) the package out of the Earth-Moon system (targeting left as an exercise for the reader).

Shielding will be a non-trivial issue, as the station at geosync will be in the Van Allen Belt, rather than below it like the ISS.  It may be that a lot of the work at the station will be done via telepresence.     

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu [mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of ROY HERREN
Sent: Monday, August 17, 2015 3:35 PM
To: The International Radiation Protection (Health Physics) Mailing List; The International Radiation Protection (Health Physics) Mailing List
Subject: Re: [ RadSafe ] space elevator

An operable space elevator would be a wonderful step towards humanities reaching out and inhabiting space.  The financial cost per kilogram of material currently launched into space is a limiting factor that is holding back greater exploration of space.  It's hard to imagine though how any one company or even country could afford to build such a complicated and large of a structure.  If this is to happen, it will likely require an international consortium for financing and construction. 
Question, where in space would such an elevator terminate, i.e. a space port, a space dock for assembling space ships, etc.?
Just to rope this discussion into the mailing list topic of concern, would deep-space manned space ships assembled in a space dock initially have fission reactors?  What would propel such ship, ion propulsion? Could deep-space space ships harvest enough interstellar gas to provide propulsion, or would they have to bring all the material with them from earth?
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