Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Sat, 30 Mar 91 02:00:58 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sat, 30 Mar 91 02:00:53 -0500 (EST) Subject: SPACE Digest V13 #325 SPACE Digest Volume 13 : Issue 325 Today's Topics: Re: railguns,superguns Magnetic projectile launcher Re: "Follies" Re: MANY QUESTIONS Re: I want to go to orbit... Space shots on CDROM for AMIGA Re: More cost/lb. follies HST update during educator satellite video conference (Forwarded) Pay as you go/Go as you pay Re: JPL spacecraft Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 27 Mar 91 04:12:14 GMT From: rochester!sol!yamauchi@louie.udel.edu (Brian Yamauchi) Subject: Re: railguns,superguns In article <7098@testeng1.misemi> stanfiel@testeng1.misemi (Chris Stanfield) writes: >In article printf@cix.compulink.co.uk (Ian Stirling) writes: >>Here in the UK there was a program on TV,about the iraqi supergun >>affair ("petrochemical" pipes were actually bits of a massive gun >>barrel) It talked about the scientist who concieved the >>idea > >The scientist in question is Gerald Bull (who was murdered under as >yet unexplained circumstances about a year ago). According to PBS's Frontline, he was assassinated by the Mossad. Evidently, it was a fairly elaborate operation, involving something like 20 agents -- most monitoring his movements, and a few performing the actual hit outside his apartment. It's interesting to speculate about what would have happened if Bull had successfully completely a gun with intercontinental or orbital launch capability. Of course, the gun would have been taken out as soon as it shelled Tel Aviv (or Washington D.C.), but the even the temporary existence of such a weapon might have been enough to spur some rather urgent interest in the development of our own gun launchers. Considering the political windfall that SDI and smart weapons have gained from the Gulf War, perhaps Sandia's coilgun and LLNL's light gas gun could have gotten a boost from an operational Iraqi supergun. I can see it now, administration officials testifying to Congress about the dire consequences of not closing the Supergun Gap... It would have been ironic if Bull, by helping an enemy of the U.S., had been able to do more for space launch technology than he was ever allowed to do when he worked from the U.S. and Canadian governments... -- _______________________________________________________________________________ Brian Yamauchi University of Rochester yamauchi@cs.rochester.edu Department of Computer Science _______________________________________________________________________________ ------------------------------ Date: Tue, 26 Mar 91 13:45:01 EST From: "S.K. Whiteman" Subject: Magnetic projectile launcher In the March 1991 issue of NASA Tech Briefs on page 48 there is a discription of a Superconducting magnetic projectile launcher. Interesting technology 8-). Sam Indiana University - Purdue University at Fort Wayne Fort Wayne, Indiana USA ------------------------------ Date: 26 Mar 91 08:19:54 GMT From: zephyr.ens.tek.com!tektronix!sequent!crg5!szabo@uunet.uu.net (Nick Szabo) Subject: Re: "Follies" In article <9103201557.AA18892@iti.org> aws@ITI.ORG ("Allen W. Sherzer") writes: > >Now figure 50 families today with two children and middle to upper income. >At $100K each raised form liquidating their net worth we have $5M. The average family net wealth in the U.S. (savings, house, car etc. minus mortgage and other debts) is near $20K, not $100K, giving us a $1M budget. >We need to >lift ~750 pounds per family (figure 500 pounds for the people and another >200 pounds for personal effects) for a total of 37.5K pounds. For 200 people, and assuming ratios somewhat better than those of the Apollo capsule and Shuttle cabin, figure in another 40,000 lb. for pressure vessel, and 40,000 lb. for life support, bringing us to 117.5K pounds. >This comes >to $133/pound which is less than two orders from current prices to LEO. This brings us to $1,000,000/117,500 = $8.51 per pound to our final destination. >Now they will need to get from LEO to the moon or some L point. However, with >access to lunar resources which will be far cheaper so I figure it rounds off >to under two order reduction. Access to lunar resources at what price? For this to be cheap requires a very diverse, automated, efficient mining and manufacturing industry. (And, BTW, the Moon cannot efficiently supply many required elements, so we might as well use asteroids and comets, which are easier to get to L-5 anyway). The contemporary rule of thumb for transport cost is a factor of 4 to GEO and spots like L-5 (the location of our proposed colony). If our destination is a planetary surface, the cost is rather higher. This brings our requirement to $2.12/lb. to LEO, in order to get to L-5. Unfortuneately, our family has spent all its money, and cannot afford to buy a home at L-5. If houses at L-5 cost half that of Earth (which also requires mature space industry), we can split 50/50 between housing and transportation costs, so that the price we really need is $1.06/lb. to LEO, which is closest to 4 orders of magnitude below current launch costs. If space industry is _extremely_ efficient and mature, and we can assume all super-LEO costs (transportation, housing, etc.) to be zero, we can use the $8.51 figure, about 3 orders of magnitude. Chem rockets cannot provide even a one order of magnitude drop, but tethers combined with suborbital airplane or laser launch, combined with very cheap EML or gas gun freight costs for the inevitable industrial "uploadings", can give us transportation for the Expansion Age. >[Need infrastructure] This is the most important point, that we need mature space mining and manufacturing technologies. This cannot be emphasized enough (and gets lost in the cost/lb. obsessions). Otherwise, space housing will remain at 300,000 times the price of earth housing, not half or zero. This issue is much more important for the Expansion Age than the launch transportation problem, and helps provide a solution for it, via tethers or other space-manufactured upper stages. >....However, this can >be provided for in the same way as all other large infrastructure jobs >are done: the government pays for it in anticipation of enough activity later >on to pay for it. Cripes. Much large infrastructure is _not_ done by the government, and when it is it is _not_ a welfare handout to would-be colonists. (Unless we are talking low-income housing, in which case we better throw in another big factor of reduction....) >ALS will not achieve an order of magnitude reduction in launch costs. In fact, >I will bet money that it ends up MORE expensive than the Shuttle. Sadly, this could be true; however the prospects for other cost/lb. ventures are not significantly better. >This program has got to be killed or we will accomplish >nothing in the 90's. I agree, and note that this reasoning applies to all $multi-billion government chemical rocket programs. There is room for incremental improvement of chemical rockets -- by _private industry_. Only private industry can judge the true limits of lauch costs. Let government work on those technologies that can provide the large, curve-changing breakthroughs. -- Nick Szabo szabo@sequent.com "If you want oil, drill lots of wells" -- J. Paul Getty The above opinions are my own and not related to those of any organization I may be affiliated with. ------------------------------ Date: 26 Mar 91 16:20:28 GMT From: dog.ee.lbl.gov!hellgate.utah.edu!caen!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo!henry@ucbvax.Berkeley.EDU (Henry Spencer) Subject: Re: MANY QUESTIONS In article <282.27EF2693@nss.FIDONET.ORG> Paul.Blase@nss.FIDONET.ORG (Paul Blase) writes: > HS> Putting the tank into orbit costs payload... > >Actually, from what I've read, it would actually ADD cargo capability. >The shuttle now has to do a complex manuver to dump the tank... You're 5+ years out of date. They don't do that any more. -- "[Some people] positively *wish* to | Henry Spencer @ U of Toronto Zoology believe ill of the modern world."-R.Peto| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 26 Mar 91 15:08:02 GMT From: vsi1!teda!ardai@ames.arc.nasa.gov (Mike Ardai) Subject: Re: I want to go to orbit... In article <1991Mar25.183132.15691@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes: -In article <1991Mar25.174621.3905@cs.mcgill.ca> msdos@cs.mcgill.ca (Mark SOKOLOWSKI) writes: -> What are the steps in order to build a reliable space-shuttle like ->spaceship in order to send myself to orbit for the summer holidays? - -First you need to locate a source of dilithium crystals. You're not going -to get off the ground without them. That won't help. Dilithium crystals are used for energy conversion in warp drives. You need either thrusters or low impulse drives until you are well outside a planet's atmosphere... /mike (visiting from the Cochrane Institure :-) -- \|/ Michael L. Ardai Teradyne EDA East --- ------------------------------------------------------------------------- /|\ ...!sun!teda!ardai (preferred) or ardai@bu-pub.bu.edu ------------------------------ Date: 26 Mar 91 17:33:24 GMT From: csus.edu!wuarchive!zaphod.mps.ohio-state.edu!usc!rpi!news-server.csri.toronto.edu!utgpu!watserv1!shine13!c8exsun@ucdavis.ucdavis.edu (Watshine - Extension Id) Subject: Space shots on CDROM for AMIGA I am thinking of purchasing a CDROM player for my AMIGA computer, and am generally interested in puchasing the Voyager pictures (and others if they are available) to view on my Amiga. What stuff is available on CDROM from NASA, and does anyone know if these CDROMs could be read from an amiga compatible CDROM drive (say XETEC, or CDTV). I've heard of the Voyager shots being in a format called VICAR. Is there a viewer available for the AMIGA computer? Or is it just for the IBM. Could someone port the viewer to the AMIGA? I've also heard that some of the CDROMs have pictures that are in condensed format. Would I be able to uncompress them on my AMIGA? I would appreciate any replies (mail would be ideal). Thanx! Jason -- --------------------------------------------------------------------------- Jason Trimble PHONE (519) 725-5397 530A Rosemeadow CR. 1B CS EEE student at the University of Waterloo Waterloo, Ont. INTERNET: c8exsun@watshine.UWaterloo.ca N2T 2A1 ------------------------------ Date: 26 Mar 91 21:07:25 GMT From: isis!isis!gaserre@uunet.uu.net (Glenn A. Serre) Subject: Re: More cost/lb. follies ... Titan rockets use chemical etching to get their tank walls thin enough.... Actually, Titan rockets only use chemical etching (chem-milling) on the tank domes (and other, similar parts). The cylindrical sections are machine-milled. It is my impression that the chem-milling is only neccessary because the edges of the sections have to be thicker so they can be welded. The newer tank domes will be machined ("spun") as one peice and so will not require chemical milling. Also, I would like to point out that Titan rockets WOULD fly if the domes weren't chem-milled, they just wouldn't lift as much payload. -- --Glenn Serre gaserre@nyx.cs.du.edu -- --Glenn Serre gaserre@nyx.cs.du.edu ------------------------------ Date: 27 Mar 91 01:38:19 GMT From: usenet@ames.arc.nasa.gov (Peter E. Yee) Subject: HST update during educator satellite video conference (Forwarded) Terri Sindelar Headquarters, Washington, D.C. (Phone: 202/453-8400) March 26, 1991 N91-23 EDITOR'S NOTE: HST UPDATE DURING EDUCATOR SATELLITE VIDEO CONFERENCE On April 2, Dr. Ed Weiler, Program Scientist for the Hubble Space Telescope (HST), will discuss the challenges encountered by the HST team as well as discuss and show images of the excellent and unique scientific findings. The April 2 conference, the last in a series of four educational video conferences conducted annually by NASA's Educational Affairs Division, will be transmitted via a Westar IV satellite, channel 19, from 2:30 to 4:00 p.m. EST. More than 30,000 educators in 50 states are expected to participate in this program. The 1-1/2 hour, interactive video conferences are designed to update teachers on NASA programs, demonstrate aerospace activities for classroom use and announce new programs, products and activities available to classroom teachers. The satellite video conference series is produced by NASA's Aerospace Education Services Project from Oklahoma State University Telecommunications Center. To register for the series, interested teachers should write to NASA Aerospace Education Services Project, Videoconference Site, 300 North Cordell, Oklahoma State University, Stillwater, Okla., 74078-0422, or call 405/744-7015. Registration is free and ensures that announcements, publications and other materials for teacher-participants are received by the school. The 1991-92 series of educational video conferences will be announced later this year. ------------------------------ Date: Tue, 26 Mar 91 09:23:38 PST From: greer%utdssa.dnet%utadnx@utspan.span.nasa.gov X-Vmsmail-To: UTADNX::UTSPAN::AMES::"space+@andrew.cmu.edu" Subject: Pay as you go/Go as you pay According to this week's (25-MAR-1991) AW&ST, Richard Truly has banned the phrase "pay as you go" from NASA's vocabulary. "Truly believes it is hard enough to garner sufficient funds when programs do have firm schedules," the article says. However, in a letter last week endorsing the revised space station, Vice President Dan Quayle wrote to Truly saying "We will 'go-as-we-pay', be we must go." _____________ Dale M. Greer, whose opinions are not to be confused with those of the Center for Space Sciences, U.T. at Dallas, UTSPAN::UTADNX::UTDSSA::GREER Separated at Birth? "Those who secede will doom themselves to failure." -- M.I.Gorbachev "If we do not succeed, then we run the risk of failure." -- J.D.Quayle ------------------------------ Date: 26 Mar 91 16:51:26 GMT From: elroy.jpl.nasa.gov!jato!mars!baalke@decwrl.dec.com (Ron Baalke) Subject: Re: JPL spacecraft In article <21413@crg5.UUCP> szabo@crg5.UUCP (Nick Szabo) writes: >nasa.gov> >Reply-To: szabo@crg5.UUCP (Nick Szabo) >Organization: Sequent Computer Systems, Inc >Lines: 19 > >In article <1991Mar20.083257.14462@jato.jpl.nasa.gov> baalke@mars.jpl.nasa.gov (Ron Baalke) writes: > >>....JPL is the only one to send spacecraft to all of >>the planets except Pluto. > >Not only that, but JPL has been _first_ to every planet, and their >Explorer probe also discovered the Van Allen belts (without which discovery, >we would have had some toasted astronauts). > I hate to disagree with you on this one, but Pioneer 10 made it to Jupiter first, and Pioneer 11 was first at Saturn, paving the way for Voyager 1 and 2. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@mars.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |___ M/S 301-355 | Change is constant. /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | |_____|/ |_|/ |_____|/ | ------------------------------ End of SPACE Digest V13 #325 *******************