Aucbvax.5457 fa.space utzoo!decvax!ucbvax!space Sun Dec 13 03:41:49 1981 SPACE Digest V2 #58 >From OTA@S1-A Sun Dec 13 03:40:36 1981 SPACE Digest Volume 2 : Issue 58 Today's Topics: Ultimate limits Space Elevator cost of power for laser launch Penthouse please Penthouse, Yes Sir! Strong cables Space Elevator ---------------------------------------------------------------------- From: FONER@MIT-AI Date: 12/12/81 22:42:02 Subject: Ultimate limits To: Space-Enthusiasts at MIT-MC I know this is a little off the subject, but as long as somebody brought it up... what ARE the ultimate limits on matter? How is the maximum theoretical strength of matter computed, and what is it? What, for that matter, is the maximum strength of single crystals, theoretical or measured? Again, what's the theoretical limit on fuel power to mass, and how is it arrived at? Any such experts out there? Thanx. ------------------------------ Date: 13 December 1981 04:42-EST From: Jerry E. Pournelle Subject: Space Elevator To: CSVAX.wildbill at UCB-C70 cc: SPACE-ENTHUSIASTS at MIT-MC Dr. Charles Sheffield, then President of AAS, did a bit on space cables out of Kevlar +; better, really, than Clarke's, and written at about the same time. HPM (Hans Moravec) has done some good analyses of space cables also; as have Minsky and Lowell Wood. ------------------------------ Date: 13 December 1981 04:48-EST From: Jerry E. Pournelle Subject: cost of power for laser launch To: VaughanW at HI-MULTICS cc: SPACE-ENTHUSIASTS at MIT-MC At then current interest rates I worked out the whole cost of building nuclear power plants in Baja Calif (thus avoiding the permit problems of building them in USA); bribing officials there; providing security; building transmission lines to the US power grid; building lasers; and setting up a launch system. The power is to be sold to the US when not used to launch spacecraft. Admittedly it is fiction, but for a multi-billion buck investment Hansen Enterprises (in my stories) got a very handsome return on investment, this in a time of economic stagnation in the US. See the book "HIGH JUSTICE" Pocket, about 1979 for details. (I make about .20 on each copy sold, so all y'all go buy one and make me rich.) JEP ------------------------------ Date: 13 December 1981 04:49-EST From: Jerry E. Pournelle Subject: Penthouse please To: Tavares.Multics at MIT-MULTICS cc: SPACE-ENTHUSIASTS at MIT-MC Incidentally, the Sheffield novel is called THE WEB BETWEEN THE WORLDS. It is perhaps not as dramatic as Clarke's (or maybe it is); it is certainly more technically detailed. It involves building a beanstalk. ------------------------------ Date: 13 December 1981 04:54-EST From: Jerry E. Pournelle Subject: Penthouse, Yes Sir! To: Hans Moravec at CMU-10A cc: SPACE at MIT-MC, Wedekind.ES at PARC-MAXC Except that it's "in principle" not "in principal" I can't think of much to disagree with. Eventually we have to escape from the rocket equation. Why not begin working on it now? ------------------------------ Date: 13 December 1981 04:57-EST From: Jerry E. Pournelle Subject: Strong cables To: FONER at MIT-AI cc: SPACE at MIT-MC One night out at Pajaro Dunes when we had nothing to do, Minsky and I (mostly Minsky) worked out the strengths and mass of cables to use a "King David" sling (centrifugal) to throw stuff off the Moon. Lo!, it's easily within the strength of Kevlar. You have to build a steel structure to give the mess rigidity, but the actual tension is held by a Kevlar cable; thus if you send up a lunar colony, Kevlar is a fairly important requirement of what to take with you. ------------------------------ Date: 13 Dec 1981 03:11:06-PST From: menlo70!sytek!zehntel!berry at Berkeley To: sytek!menlo70!ucbvax!space@Berkeley Subject: Space Elevator The space elevator was the subject of quite a bit of recent writing, not the least of which was the novel "The Fountains of Paradise" by Arthur C. Clark. At about the same time that this book was published, another author/scientist published another novel on the same subject. An extract from the novel, and an article desciribing the system in more mathematical detail than is possible in a novel appeared in Destinies, a paperback magazine (bookazine? magazook?) formerly published by Ace. I am afraid I can remember neither the date of the issue, nor the author's name, because my copy is still in one of the boxes piled in what will soon (Klono willing) be my library. Perhaps Dr. Pournelle can supply us the name/dates?? -Berry Kercheval ------------------------------ 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.