Aucbvax.5580 fa.space utzoo!decvax!ucbvax!space Sun Dec 27 03:18:56 1981 SPACE Digest V2 #71 >From OTA@S1-A Sun Dec 27 03:06:21 1981 SPACE Digest Volume 2 : Issue 71 Today's Topics: North Pole Cables to an SPS ---------------------------------------------------------------------- Date: Saturday, 26 December 1981 15:13-CST From: Jon A. Webb To: Space at MC Subject: North Pole cc: cs.webb at UTEXAS-20, REM at MC I guess it's not immediately obvious that skyhooks can only be attached to the equator, not to the north pole, since geosynchronous orbit is possible only in the plane of the equator. Jon ------------------------------ Date: 26 Dec 1981 00:05:43-EST From: p-btempl at CCA-UNIX (Brad Templeton) To: space at Mit-mc Subject: Cables to an SPS It occurs to me that even aiming at a reception station just above the atmosphere for cable transmission down to earth would not stop the complainers - it might cause them to complain more. If the SPS is at geosync orbit, then a station a few hundred miles up is effectively on the earth for most of the rotation cycle, so there would be lots of earth beyond the path of the beam, and worst of all, not just one place (like the desert) Instead a whole circle of danger is sweeped out if any leakage occurs. What are the figures on how much power can be stored in how much mass of chemical fuel? For example, is it practical at all to use SPS power to create fuel cells from (say lunar) raw materials, by things such as the electrolization of water? Could this fuel then be dumped right onto the earth for parachute pickup, or is the container cost too high? If the container cost is high, then perhaps the power canisters could be fired (safely, assuming we can catch them easily) to the top of a small (200 km high or so) skyhook, and sent down to Earth for whatever use. (ie. reconverted to electricity (somewhat inefficient) or pumped down in fuel form) Anyway, the canisters, and even the raw materials can then be shot back up to the SPS for re-use. On the ion lifted skyhook, I think this is pretty unlikely. Even if you cut the weight in half, you don't save much in taper, and you need the power from your engines capable of supporting what you wanted to support with your strong material. Probably easier to lift everything up by STS! Besides, might there not be an effect from the constant stream of energy going along the cable? I think with our current technology, the low orbit rotating hook is the only way we can go right now. It's a good stepping stone to the geosyncronous one. A hook is much preferable to a linacc, since the linacc is only of use to cargo, and people are forced to take something like the STS up. This means that most of us, who want to go up (at least for a visit) might not get the chance before we buy it. ------------------------------ End of SPACE Digest ******************* ----------------------------------------------------------------- gopher://quux.org/ conversion by John Goerzen of http://communication.ucsd.edu/A-News/ This Usenet Oldnews Archive article may be copied and distributed freely, provided: 1. There is no money collected for the text(s) of the articles. 2. The following notice remains appended to each copy: The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996 Bruce Jones, Henry Spencer, David Wiseman.