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 ; Thu, 6 Jun 91 02:36:44 -0400 (EDT) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Thu, 6 Jun 91 02:36:39 -0400 (EDT) Subject: SPACE Digest V13 #608 SPACE Digest Volume 13 : Issue 608 Today's Topics: Re: Calculating delta-V Re: Budget Numbers Wanted Re: Crater Found From 65-Million Year Old Asteriod Re: Laser launchers (really microwave launchers) Re: Privatization Amateur Telescope Making Re: Rational next station design process Mars Info Requests Re: vacuum energies for propolsion Re: Rational next station design process Asteroid Hazard Avoidance Glavkosmos Joint Ventures Re: Budget Numbers Wanted Re: Asteroid Hazard Avoidance 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: 24 May 91 03:21:48 GMT From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: Calculating delta-V In article <16394.283cd090@levels.sait.edu.au> steven@rex.sait.edu.au writes: >... My question is what is the >standard (if there is one) that rocket scientists use for g? ... You just have to look at the fine print in whatever document you are using. Sutton says the "standard" is 9.8066 m/s^2, but (for example) the Thiokol solid-motor catalog specifies 9.80665. >A good solution is to give SI as the ratio of thrust (in Newtons) to >propellant consumption (in kg/s). This will give SI in m/s ... In fact, this amounts to forgetting specific impulse entirely and simply stating the effective exhaust velocity. Definitely the right approach. -- And the bean-counter replied, | Henry Spencer @ U of Toronto Zoology "beans are more important". | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 24 May 91 03:16:46 GMT From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: Budget Numbers Wanted In article <1991May23.224629.9916@csun.edu> swalton@corona.csun.edu (Stephen Walton) writes: >My letter did not bash Fred. I mentioned no other government programs, >merely wrote a short letter stating my support for the Augustine >Commission recommendations... Unfortunately, this is naive. As I've mentioned before in other connections, you must always consider not just the wording of what you are signing, but how it will be perceived and used. You may not have *said* "kill Fred", but your letter was almost certainly counted in the "kill Fred" column. Don't delude yourself; this is politics, not mathematics. -- And the bean-counter replied, | Henry Spencer @ U of Toronto Zoology "beans are more important". | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 22 May 91 14:47:32 GMT From: rochester!dietz@louie.udel.edu (Paul Dietz) Subject: Re: Crater Found From 65-Million Year Old Asteriod In article <834@newave.UUCP> john@newave.mn.org (John A. Weeks III) writes: >what I read (and partly understand). The dinosaurs did not die out in >one instant. The extinction appears to have taken hundreds if not thousands >of years. This could be consistant with a climate change, but one might >expect the effects of a major impact to be more immedieate. This reasoning is odd indeed. The dinosaurs were around for more than 100 million years. Impacts (or whatever) on the scale of the KT boundary (CT refers to another boundary) are very rare, as has been confirmed by the absence of similar iridium anomalies elsewhere in sediments. It would be an enormous coincidence indeed if the were to die out within a few hundred or thousand years of such a rare event, unless the extinction and the iridium event are causally connected. I suspect the answer is that the dinosaurs were not dying out at the time; I understand sampling errors near sharp cutoffs can give the illusion of slow decline when none exists, especially in large, rare organisms such as dinosaurs where the spacing between fossils is large (and the temporal resolution is therefore low). Oceanic microfossils of other kinds of organisms appear to document a knife-sharp discontinuity, as do pollen grains in continental fossils. Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: 21 May 91 18:27:53 GMT From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!uupsi!cci632!ritcsh!ultb!krf1061@tut.cis.ohio-state.edu (K.R. Flanagan ) Subject: Re: Laser launchers (really microwave launchers) In article <386.2838ECB9@nss.FIDONET.ORG> Paul.Blase@nss.FIDONET.ORG (Paul Blase) writes: >to: johnsson@cs.chalmers.se (Thomas Johnsson) > > TJ> I wonder if anyone has considered beaming the power to the > TJ> launch vehicle using microwaves instead of a laser. Presumably > TJ> power can be converted to microwaves with greater efficiency > TJ> than laser light. In the vehicle end, the beamed power could > TJ> either heat up a medium direcly, or be converted to electricity > TJ> (a lot!) with a rectenna to drive a mass driver. > >The trouble is the size of the rectenna required. NASA has already built a >microwave powered airplane, for long-duration upper atmospheric studies. >The thing (unmanned, of course) looks like a cross between a U-2 and >an AWACS, the big circular thing being the rectenna > >--- via Silver Xpress V2.26 [NR] >-- >Paul Blase - via FidoNet node 1:129/104 >UUCP: ...!pitt!nss!Paul.Blase >INTERNET: Paul.Blase@nss.FIDONET.ORG Sounds interesting, detials, details please, and references if possible. Just another college student during finals; -Kevin Flanagan krf@vaxc.isc.rit.edU. ------------------------------ Date: 22 May 91 17:21:31 GMT From: agate!spool.mu.edu!rex!rouge!dlbres10@ucbvax.Berkeley.EDU (Fraering Philip) Subject: Re: Privatization Would people please be careful with the nested attributations? The post by H. Rubin may or may not have attributed something Jonathan Leech wrote to me (although perhaps not; I sort of wonder who that Fraering Philip person is who keeps posting the same things I do). -- Phil Fraering || Usenet (?):dlbres10@pc.usl.edu || YellNet: 318/365-5418 ''It hardly mattered now; it was, in fact, a fine and enviable madness, this delusion that all questions have answers, and nothing is beyond the reach of a strong left arm.`` - Larry Niven and Jerry Pournelle, _The Mote in God's Eye_ ------------------------------ ReSent-Message-ID: Resent-Date: Thu, 23 May 91 09:17:09 EDT Resent-From: Harold Pritchett Resent-To: Space discussion group Date: Wed, 22 May 91 12:40:29 CDT From: THE GAR Subject: Amateur Telescope Making A trip to a nearby library at lunch yielded three books in my search: Amateur Telescope Making: Book One (1959) from Scientific American Amateur Telescope Making: Book Two Standard Handbook for Telescope Making by N.E.Howard (also 1959) I look forward to hearing any comments on my chosen (by availability) texts and suggestions regarding new techniques or sources which may have emerged in the last 32 years. /++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\ ! Later + Systems Programmer ! ! Gary Warner + Samford University Computer Services ! ! + II TIMOTHY 2:15 ! \+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/ ------------------------------ Date: 21 May 91 18:33:53 GMT From: van-bc!rsoft!mindlink!a684@ucbvax.Berkeley.EDU (Nick Janow) Subject: Re: Rational next station design process gwh@headcrash.Berkeley.EDU (George William Herbert) writes: > This isn't how space programs funding is done now... That's your argument? We should decide to go ahead with a vague project, _then_ decide the details, like who can/will use it and who might be willing to pay for the services, just because "that's the way they do it now"? > The President and VP seem to want Freedom, whatever the cost. Political advertising is a really poor excuse for an otherwise unrelated engineering project. > ) we've already decided how much one is worth. Really? I thought the project was still undefined, so how could there be a firm cost to be accepted? The cost projections seem more like tools used for the current round of budget fighting, with no real meaning beyond that. Nick_Janow@mindlink.bc.ca ------------------------------ Date: 21 May 91 07:57:29 GMT From: pdn!moody@uunet.uu.net (Steve Moody) Subject: Mars Info Requests I am about to embark on a research endeavour to aquire as much information as I can about Mars, Future Mars Missions, Theories and Proposals for Colonization, and or Exploration of our sister planet. I need to point out that this is a personal project, and not one that is affiliated with any organization. I also wish to point out that it is nonetheless important to me and I intend to treat it as such. I have access to ftp sites only through mailservers, so any bulk information must either be sent to me directly or directions to acess it through the mail system must be prescribed. It is my hopes that eventually thisdata gathering will culminate in some writing submissions. I appreciate any help given and my thanks to all who help. Steve Moody -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Steve Moody AT&T Paradyne ~~ moody@pdn.par adyne.com Mail stop LG-130 ~~ P.O Box 2826 ~~ Largo, Fla 34649-2826 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ------------------------------ Date: 21 May 91 15:45:15 GMT From: agate!spool.mu.edu!think.com!zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!sun-barr!ccut!wnoc-tyo-news!astemgw!kuis!rins!will@ucbvax.Berkeley.EDU (will) Subject: Re: vacuum energies for propolsion In article <280@rins.ryukoku.ac.jp>, will@rins.ryukoku.ac.jp (will) writes: >all the oceans of Earth. Another estimate by Jojn Wheeler gives Sorry, should be John Wheeler. Also, does anyone know where Dr. Robert Forward is and how to contact him? William Dee Rieken Researcher, Computer Visualization Faculty of Science and Technology Ryukoku University Seta, Otsu 520-21, Japan Tel: 0775-43-7418(direct) Fax: 0775-43-7749 will@rins.ryukoku.ac.jp ------------------------------ Date: 21 May 91 22:39:51 GMT From: agate!headcrash.Berkeley.EDU!gwh@ucbvax.Berkeley.EDU (George William Herbert) Subject: Re: Rational next station design process In article <5936@mindlink.bc.ca> Nick_Janow@mindlink.bc.ca (Nick Janow) writes: >I agree with Nick Szabo: you have decided the project will go ahead, and are >looking for ways to justify it. No, but anyway... >IMO, the proper approach is to first find out who is wiling to pay for a space >station; then how much are they wiling to pay, for how much/what kind of >service. It may be that the taxpayers are willing to pay $x billion for >research, exploration and national pride. The "Industrial Competitiveness" >branch of the government may be willing to allocate $x billion for >space/power/time in microgravity for materials and biological research. Some >private corporations might also be willing to spend $x billion for services>. The military may allocate a certain amount of funds for aerospace >R&D, certain services, etc. >Once you find out who is willing to pay for what sort of services, you can >start defining what sort of structure is required to meet those demands and >whether or not they can be provided at the price offered. This isn't how space programs funding is done now... Besides which, we've already Heard how much we're willing to spend. Depending on who you listen to, (congress wants something at or under the NASA estimate (30-50 billionish) as opposed to the Congressional estimate of about 100 billionish. The President and VP seem to want Freedom, whatever the cost.) we've already decided how much one is worth. -george william herbert gwh@ocf.berkeley.edu ------------------------------ Date: 23 May 91 17:02:20 GMT From: STENGEL@pucc.princeton.edu (Robert F. Stengel) Subject: Asteroid Hazard Avoidance According to Aviation Week (6/4/90): "Asteroids hurtling toward Earth are suff iciently large and numerous that the (AIAA) persuaded Vice President Dan Quayle to mention the threat in a recent speech. The impact of an asteroid that whiz zed by in 1989 would have equalled 1,000-2,500 one-megaton hydrogen bombs. The AIAA says the asteroid passed through Earth's orbit just 6 min. after the plan et was there, and no one saw it coming." How about some discussion ... ------------------------------ Date: Wed, 22 May 91 08:09:24 PDT From: greer%utdssa.dnet%utadnx@utspan.span.nasa.gov X-Vmsmail-To: UTADNX::UTSPAN::AMES::"space+@andrew.cmu.edu" Subject: Glavkosmos Joint Ventures I found an interesting tidbit in _Soviet Business & Trade_, Vol.XIX, Iss.6, April 17, 1991. News of this may have appeared on the net before, but if it did I missed it. The Soviet commercial space agency Glavkosmos is codeveloping four 18 ton satellites which are ultimately intended to provide direct-broadcast television to homes throughout the USSR. Unnamed German coporations are participating in the design, development, and financing of the satellites, which will be five times heavier than any other satellite launched into a geosynchronous orbit. The project was revealed by Mr. Alexander Dunaev, chairman of Glavkosmos, before an audience of US aerospace executives. He said Glavkosmos is willing to consider additional foreign participation in the project, including American coporate participation. The preliminary timetable calls for launching the first of the satellites in 1994. Three satellites will suffice for broadcasting television throughout the USSR, and the fourth would provide global coverage. Their signals are intended to be received by satellite dishes 1.5 feet (0.5 meter?) in diameter located on rooftops of houses and apartment buildings. Mr. Dunaev also said the Almaz radar mapping system would go commercial. Almaz images will have a resolution of 20 meters and will be marketed in the US by the Texas based Space Commerce Corporation. _____________ 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 "Mars is essentially in the same orbit as the Earth. Mars is somewhat the same distance from the Sun, which is very important. We have seen pictures where there are canals, we believe, and water. If there is water, there is oxygen. If oxygen, that means we can breathe." -- J. Danforth Quayle, 18 November, 1989 ------------------------------ Date: 23 May 91 22:45:48 GMT From: sequent!muncher.sequent.com!szabo@uunet.uu.net Subject: Re: Budget Numbers Wanted In article <1991May23.052535.18298@agate.berkeley.edu> fcrary@earthquake.Berkeley.EDU (Frank Crary) writes: >As can be seen from Stephen Walton's post, most programs did not recieve >"the money taken away from Freedom" the following items are the only ones >to recieve more money without Freedom as opposed to with Freedom: [3 items, including LANDSAT] >The following did not LOOSE money, as a result of the deletion of Freedom: [11 items, including SETI, SIRTF, AXAF, EOS, CRAF, and NASP] What is the difference between not losing money to Fred, and getting money taken away from Fred? _Both_ of these categories -- a good chunk of NASA's valuable programs -- have greatly benefited in this budget from the Fred cut. Drawing any other conclusion is, to quote some nay-sayer, "dreaming". -- Nick Szabo szabo@sequent.com "If you understand something the first time you see it, you probably knew it already. The more bewildered you are, the more successful the mission was." -- Ed Stone, Voyager space explorer ------------------------------ Date: 24 May 91 01:08:43 GMT From: leech@apple.com (Jonathan Leech) Subject: Re: Asteroid Hazard Avoidance In article <1991May24.000159.23411@sequent.com> szabo@sequent.com writes: >that has already been made during the last decade by the great explorers >Eleanor Helin and Eugene Shoemaker. Don't forget Carolyn Shoemaker while you're at it. ------------------------------ End of SPACE Digest V13 #608 *******************