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 ; Sun, 7 Apr 91 01:48:46 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sun, 7 Apr 91 01:48:41 -0500 (EST) Subject: SPACE Digest V13 #374 SPACE Digest Volume 13 : Issue 374 Today's Topics: Timberwind fallout Eclipse Photography Re: Underground Nuclear Test in Nevada Re: HST in-orbit Maintenance Re: NY Times Article: Nuclear rocket Re: Nova: The Dark Side of the Moon Re: Space Stations, Money, Startrek Re: Space Stations, Money, Startrek Space-Investors List Re: Commercial Space news (5 of 12) Re: Space Stations, Money, Startrek Re: Timberwind fallout mexico/eclipse:need info! 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: 4 Apr 91 22:49:55 GMT From: hpda!hpcupt1!hpisod2!jem@ucbvax.Berkeley.EDU (Jim McCauley) Subject: Timberwind fallout Who among your has any really good stuff on the recently-blown (that is to say, formerly black-budgetted) Timberwind nuclear heavy-lift launch vehicle project? I'm particularly interested in any connections that Tinberwind may have had with the old Dumbo high-thrust nuclear rocket program that limped through Los Alamos in the late 1950s, starved for cash because all the nuclear rocket money was going to the high-impulse Rover/NERVA program. Jim McCauley jem@hpulpcu3.cup.hp.com Disclaimer: I speak the truth, but only on my own behalf. ------------------------------ Date: 5 Apr 91 16:54:32 GMT From: ubc-cs!alberta!herald.usask.ca!ccu.umanitoba.ca!bison!sys6626!draco!swrdpnt!ford@beaver.cs.washington.edu (Ford Prefect) Subject: Eclipse Photography One point tht should be mentioned to prospective eclipse photographers: Don't expect to get good results with new equipment that you bought just for the eclipse! You should be completely familiar with your camera system, and should have done some photography of the moon with it before. The suggestion of making a checklist of exposure times and f/stops is a good idea. Another idea is to practise your routine over and over until you can do it with your eyes closed. Then try it in a dark room. It gets quite dark during totality, so knowing your equipment is essentia to get good results. If you're travelling to Mexico, the sun will be nearly overhead during totality, so a useful accessory is a right-angle focussing magnifier. It will make things easier on your neck. Above all, don't spend the whole time photographing; LOOK at it! A solar eclipse is an awsome sight that will live in your memory much more vividly than your best photograph of it. Scott Young ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Reply to: ford%swrdpnt.bison.mb.ca@niven.ccu.umanitoba.ca ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ------------------------------ Date: 7 Apr 91 00:10:13 GMT From: fernwood!portal!cup.portal.com!mmm@apple.com (Mark Robert Thorson) Subject: Re: Underground Nuclear Test in Nevada Hema Murty says: > Yesterday there was another underground nuclear test in > Nevada. Why are we allowing this to continue? I agree that it's a disgrace that underground nuclear testing is allowed to continue. I've always wanted to see a nuclear explosion from the closest possible safe distance, and underground testing has denied me this chance. Furthermore, the termination of open-air testing is what really put the kabosh on nuclear-powered launch vehicles, which are vitally important to the construction of large-scale space habitats and manned exploration of the solar system. What's really galling is that even our smallest and cleanest bombs can't be used above-ground, which puts a severe crimp in some of the most promising anti-missile technologies. Let's join Hema Murty's call for an end to underground testing! ------------------------------ Date: 6 Apr 91 22:07:56 GMT From: agate!bionet!uwm.edu!zaphod.mps.ohio-state.edu!rpi!mvk@ucbvax.Berkeley.EDU (Michael V. Kent) Subject: Re: HST in-orbit Maintenance In article <1991Apr6.162745.13342@kcbbs.gen.nz> George_Muzyka@kcbbs.gen.nz (George Muzyka) writes: >Method: >1. Assembly a large cubical frame structure made up of trusses and beams, > much like on one of the U.S. Shuttle missions; the Large Array. (?) >2. Manouevering of this cubical frame so the target spacecraft/satellite > is within its centre. Need plenty of leeway space, but also some > beams with attachment arms to temporarily hold the target object > still in attitude relation to the frame. >3. The covering of the cubical frame with a temporary skin, to hold > in any small or medium-sized items that may slip out of astronaut > gloves and drift away. Aid of a laser sensitive moving debris device > could show where a small item is heading. The skin/covering material > could be lined with a catchy texture (not a sticky adhesive!) to > prevent rebounds/deflections. >4. The target spacecraft/satellite could now be opened and large > sections separated with the attachment arms keeping hold of each > section. >5. After in-orbit repair, and reassembly, one side of the cubic frame's > covering could be removed and the whole framework carefully manoeuvered > away from the target, and the framework probably dismantled until > next time. > [Further info on in-orbit servicing deleted.] >George_Muzyka@kcbbs.gen.nz | / /~~ >Kappa Crucis Unix BBS, Auckland |_/ /\ |~\ |~\ /\ | |~ | | /~ | (~ >NEW ZEALAND. Ph. +64 9 817 3725 | \ \,\ |,/ |,/ \,\ | | |_| \_ | _) >Fidonet 3:772/90.0 | \ | | \__ Such a servicing bay was indeed planned for Freedom. If you've seen any pictures of Freedom Phase II you may have noticed a large white structure in an upper corner of the rectangular frame. This was to be a satellite serviceing facility, and it was to be large enough to hold any of the Great Observatories. Tools would be stored there to aid in refueling and refurbishing satellites. I believe it may have been pressurized too, but I'm not sure. That eliminates problems concerning the gloves and bulky suits. These plans are a few years old and date back to the time when NASA planned to have an Orbiting Maneuvering Vehicle parked at the Station and and Orbiting Transfer Vehicle to ferry satellites to and from GEO for repair. Michael Kent mvk@itsgw.rpi.edu ------------------------------ Date: 6 Apr 91 17:30:25 GMT From: agate!bionet!uwm.edu!cs.utexas.edu!ut-emx!nowhere!sking@ucbvax.Berkeley.EDU (Steven King) Subject: Re: NY Times Article: Nuclear rocket In article <2257@cluster.cs.su.oz.au> ray@cluster.cs.su.oz.au (Raymond Lister) writes: > > WASHINGTON (UPI) -- The Pentagon is trying to build a nuclear-powered >rocket to boost huge payloads, satellites or weapons into space, >scientists and government sources said Wednesday. > Rather than using conventional chemical rocket fuels to generate a >blast of hot gases to propel a rocket into space, the project involves >vaporizing liquid hyrdogen into a far stronger exhaust stream by passing >it over a bed of nuclear fuel pellets generating heat as high as 3,000 >degrees. > Internal government documents, obtained on the condition that their >source not be divulged, show the program is still young and years away >from completion. The documents also say the government already has >studied safety hazards that might be associated with a sub-orbital test >flight that could pass over the Antarctic and New Zealand. Eh? This sounds like the old fashioned "project in search of a mission" combined with media hyperbola. The fluidized bed reactor project ( scandi ? ) has been around atleast since the mid eighty's. I first saw papers reguarding it as a part of an aero & astro class at the UW; it couldnt have been too highly classified, as it was availible to students. At that time it was being proposed a megawatt powersupply for space applications that would need lots of power very quickly and for a short period ( ie. SDI ). It would use the superheated hydrogen to drive turbines to drive the generators... I wouldnt be surprised if this wasnt more of the same; that is, proposals and funding to keep research ongoing as opposed to a "real" project. There were, as I remember, a few technical problems to be considered. Pump too much energy into diatomic hydrogen and it tends to disassociate, sucking up a substancial amount of energy, pump more energy into it and one gets a wild mixture of H-, H+, H2, etc., this both limits the specific impulse and produces a very reactive exhaust that needs to be considered in the design of the nozzle and even the fuel pellets. I can't, for the life of me, remember how it was to be moderated. But I do remember that if the vehicle was forced to undergo reentry, the proposal called for the fuel to be discharged at a high altitude so that the fuel pellets would be vaporized and any radioactive residue would be uniformly distributed... -- If it don't stick, stink, or sting It ain't from Texas. ..!cs.utexas.edu!ut-emx!nowhere!sking ------------------------------ Date: 7 Apr 91 03:57:10 GMT From: wr0k+@andrew.cmu.edu (William Dow Rieder) Subject: Re: Nova: The Dark Side of the Moon Henry Spencer writes: >Don't know, I haven't seen the program. :-) (I don't own a television set.) ^^^^^^^^^^^^^^^^^^^^^^ You have my deepest respect :-) I didn't used to have one, but my wife did when we got married. Oh well. Saves a lot of your time, I'll bet. W. Dow Rieder When the only tool you have is a hammer, all your problems start to look like nails... ------------------------------ Date: 6 Apr 91 22:23:33 GMT From: dog.ee.lbl.gov!hellgate.utah.edu!caen!zaphod.mps.ohio-state.edu!rpi!mvk@ucbvax.Berkeley.EDU (Michael V. Kent) Subject: Re: Space Stations, Money, Startrek In article <10941@ncar.ucar.edu> steve@groucho.ucar.edu (Steve Emmerson) writes: >In <.6+g+vn@rpi.edu> mvk@aix01.aix.rpi.edu (Michael V. Kent) writes: > >>... The major >>task for Freedom is to learn how to live and work in space. Once we have >>that we can work on expanding the facilities. > >Odd. Don't we (i.e. the human species) already know how to live and >work in space? Haven't humans spent up to a year in space with no >major problems? No, WE don't. WE have only been to space for brief visits, with the exception of an 84 day mission in 1973. While it did provide valuable data, it answered only a few or our questions -- questions which need to be answered. There are some humans which know more than we do, but since WE don't have access to their data, we'll have to learn ourselves. True, we will be re-inventing the wheel, but the cart is our own invention. > >>..e Fourth, astronauts will spend about 1.5 hours a day exer- >>cising. One of the things we need to know is what exercise is necessary >>and why. Freedom will help provide that answer. > >Odd. Don't we already know the answer to these questions? (And isn't the >necessary amount of excercise closer to 4 hours per day?) Obviously not. :) From "Space Station Freedom: A Foothold on the Future"... "To maintain physical fitness each crew member will go through two 45-minute, individualized exercise programs a day using the treadmills and stationary bicycles in the habitation module." This is based on experience with Skylab and the Space Shuttle. Granted, this may turn out to be inadequate, but then we will answer your other question with "No, we didn't know." > >Steve Emmerson steve@unidata.ucar.edu ...!ncar!unidata!steve Michael Kent mvk@itsgw.rpi.edu ------------------------------ Date: 6 Apr 91 18:28:40 GMT From: groucho!steve@handies.ucar.edu (Steve Emmerson) Subject: Re: Space Stations, Money, Startrek In <.6+g+vn@rpi.edu> mvk@aix01.aix.rpi.edu (Michael V. Kent) writes: >... The major >task for Freedom is to learn how to live and work in space. Once we have >that we can work on expanding the facilities. Odd. Don't we (i.e. the human species) already know how to live and work in space? Haven't humans spent up to a year in space with no major problems? >... Fourth, astronauts will spend about 1.5 hours a day exer- >cising. One of the things we need to know is what exercise is necessary >and why. Freedom will help provide that answer. Odd. Don't we already know the answer to these questions? (And isn't the necessary amount of excercise closer to 4 hours per day?) Steve Emmerson steve@unidata.ucar.edu ...!ncar!unidata!steve ------------------------------ Date: 5 Apr 91 04:32:00 GMT From: sgi!cdp!kdonow@ucbvax.Berkeley.EDU Subject: Space-Investors List Can anyone provide the Internet or Bitnet address for the space-investors list? I've shifted accounts and seem to have left that information behind. Thanks in advance. Ken Donow W.L. Pritchard & Co. 7315 Wisconsin Avenue Suite 500E Bethesda, MD 20814 Voice: 301-645-1144 Fax: 301--654-1514 Email:[ cdp!kdonow@labrea.stanford.edu ------------------------------ Date: 6 Apr 91 21:55:18 GMT From: swrinde!zaphod.mps.ohio-state.edu!rpi!mvk@ucsd.edu (Michael V. Kent) Subject: Re: Commercial Space news (5 of 12) In article <10351@hub.ucsb.edu> 3001crad@ucsbuxa.ucsb.edu (Charles Frank Radley) writes: >Oh yes, when the ELV companies say they are not subsidized by the >US govt, ask who owns their tooling....... > A paraphrasing of Art Dula quoted in the LA Times. Is this a trick question? Who do you think owns their tooling? Michael Kent mvk@itsgw.rpi.edu ------------------------------ Date: 7 Apr 91 00:10:02 GMT From: usc!rpi!news-server.csri.toronto.edu!utzoo!henry@apple.com (Henry Spencer) Subject: Re: Space Stations, Money, Startrek In article <10941@ncar.ucar.edu> steve@groucho.ucar.edu (Steve Emmerson) writes: >Odd. Don't we (i.e. the human species) already know how to live and >work in space? Yes, in the sense that we know some approaches that work. No, in the sense of knowing all there is to be known about it, and being able to estimate the effectiveness of new approaches before trying them. >Haven't humans spent up to a year in space with no major problems? Two humans have done this, without major problems. More data would be very welcome, since future efforts are unlikely to precisely duplicate the exact set of conditions under which this was done. We have an existence proof, but not enough data to confidently draw graphs and define the boundaries between acceptable and unacceptable conditions. >>... One of the things we need to know is what exercise is necessary >>and why... > >Odd. Don't we already know the answer to these questions? No. We have vague notions at best. What's wanted is enough detailed knowledge to guide engineering design of future space activities. That we do not have. -- "The stories one hears about putting up | Henry Spencer @ U of Toronto Zoology SunOS 4.1.1 are all true." -D. Harrison| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 7 Apr 91 04:37:31 GMT From: usc!rpi!news-server.csri.toronto.edu!utzoo!henry@ucsd.edu (Henry Spencer) Subject: Re: Timberwind fallout In article <11140002@hpisod2.cup.hp.com> jem@hpisod2.cup.hp.com (Jim McCauley) writes: >I'm particularly interested in any connections that Tinberwind may >have had with the old Dumbo high-thrust nuclear rocket program ... If the descriptions of Timberwind's hardware -- a fluidized-bed pellet-fuel reactor -- are correct, none whatsoever. >all the nuclear rocket money was going to the high-impulse Rover/NERVA >program. Uh, we may have a slight misunderstanding here: Dumbo had *both* higher thrust and higher exhaust velocity (aka specific impulse) than NERVA. The difference between the two was ambitious high-performance vs. cautious low-performance, so it's no surprise which got canned when money was tight. -- "The stories one hears about putting up | Henry Spencer @ U of Toronto Zoology SunOS 4.1.1 are all true." -D. Harrison| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 6 Apr 91 18:53:34 GMT From: agate!bionet!uwm.edu!zaphod.mps.ohio-state.edu!casbah.acns.nwu.edu!uicvm.uic.edu!u29012@ucbvax.Berkeley.EDU Subject: mexico/eclipse:need info! I am travelling down to Mexico this July to view/photograph the eclipse. We are trying to arrane it so we will be in Tuxpan on the day of the eclipse. There is also a chance that we will be in Guadalajara (sp?) on that day. Does anyone have the times that the eclipse is supposed to occur? We need the info ASAP so we can make travel arrangements. Thanks in advance. Christina U29012@UICVM (bitnet) u29012@uicvm.uic.edu (internet) ------------------------------ End of SPACE Digest V13 #374 *******************