Date: Sat, 12 Dec 92 05:13:28 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #536 To: Space Digest Readers Precedence: bulk Space Digest Sat, 12 Dec 92 Volume 15 : Issue 536 Today's Topics: "trivial engineering" absolutely, positively overnight (2 msgs) Aurora Cassini Undergoes Intensive Design Review DC-1 passenger service DC vs Shuttle capabilities (3 msgs) Galileo Update - 12/08/92 Hubble's view of the universe Orbit Question? Saturn V fates Scud Missile technology (2 msgs) Scuttle replacement Trees in space... Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: Fri, 11 Dec 92 21:48:01 EST From: John Roberts Subject: "trivial engineering" -From: ewright@convex.com (Edward V. Wright) -Subject: Re: Terminal Velocity of DCX? (was Re: Shuttle ...) -Date: 11 Dec 92 17:28:26 GMT -Organization: Engineering, CONVEX Computer Corp., Richardson, Tx., USA -By that logic, every jet-engine design is a "radically new technology." -This "isn't trivial engineering that can be brushed aside by saying -it's been done before with other engine designs... It *should* work, -but they won't know until they try it what problems may develop." For -some reason, I don't see airliners falling out of sky because of the -"radically new" engines that are introduced, quite regularly, every -few years. Somebody (I think it was Goldin) commented recently on a jet engine company's recent design of the new engine. The design process cost something around a billion dollars - they hope to sell enough to pay off the design cost in 20 years. And it wasn't a radical new design - it just gets a few percent improvement in power or efficiency compared to an existing engine. (I would *hope* that designing a throttleable RL-10 or an RL-200 costs less than a billion dollars, but I can't say for sure. A large part of the cost has to be for testing.) One advantage for rocket engine technology is that it's "younger" than jet engine technology - a relatively inexpensive change could possibly result in a significant improvement. ->>Saying that doesn't make it so. The engine is about as "radically ->>new" as a new microprocessor. The cost of designing a new microprocessor can also approach a billion dollars. (Not sure of the exact magnitude - >$100 million appears to be fairly common.) -It's amazing that things we did routinely in the 1960's are considered -challenging today. I guess we've lost a lot of technology since then, -right? If Goldin has his way, I suspect a lot of new things will be tried. Those "smaller, faster, cheaper" spacecraft could be used to test advanced propulsion systems, for instance. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 11 Dec 92 04:18:10 GMT From: Greg Moore Subject: absolutely, positively overnight Newsgroups: sci.space In article henry@zoo.toronto.edu (Henry Spencer) writes: >In article jbh55289@uxa.cso.uiuc.edu (Josh 'K' Hopkins) writes: >>I'm no expert on jet lag. It just seems like going from breakfast to a late >>dinner in the time it takes to skim a good magazine would have to throw your >>system off. Since jet lag is way off the subject... > >Actually, not entirely off the subject. > >The problem in jet lag is the timezone change from origin to destination. >How long it takes to get there is, to a first approximation, irrelevant. >Although the airlines often make some attempt to smooth the transition, >you can think of the situation as staying on origin time until you step >off the plane, at which point you suddenly have to shift to destination >time. > I'll ahve to check wth an ex-roommate on this (she did her thesis on jet lag) but I ebleive that length of time IS important. It and the difference in time between time zones is what affects people. >However, on closer examination, trip time is relevant... because a long >fatiguing trip can only make the problem worse. The shorter the better. > Fatigue is only part of the the problem. The shorter the better is true in the sense that less fatigue and all, but, your clock is somewhat more out of whack. Also, a quick trip time may have a different effect. If it is only a 90 minute flight to Europe from North America, you may see people popping over for a meeting or the like, and then popping back the same day. That way they don't have to deal with eating and sleeping out of sync. >On the other hand, note that the Concordes seldom have many empty seats. >Their market niche may be limited, but they do make an operating profit. >You might be able to run scheduled DC-1 service on one or two well-chosen >routes. > On another note, tehre is still some talk about building Concorde II for Trans-pacifc flights. One problem with the Concorde is the limited amount of passanger space. Several studies ahve indicated that a large supersonic jet (200-400 passengers) could be profitable on flights to the East Rim. >I'm sure that if certification were suitable and appropriate facilities >were widespread, there'd be a few executive DC-1s bought. The Saudi >royal family would surely buy one. And then there's Air Force One... >-- >"God willing... we shall return." | Henry Spencer @ U of Toronto Zoology > -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 11 Dec 92 16:51:26 GMT From: Henry Spencer Subject: absolutely, positively overnight Newsgroups: sci.space In article <1g8obrINN78b@uwm.edu> anthony@csd4.csd.uwm.edu (Anthony J Stieber) writes: >>But they didn't call the SR-71 the Recon-STRIKE-71 before LBJ's mangling for >>nothing. > >Yep. And I also heard about the drone launch accident that downed both >the drone and the host SR-71... That actually happened in pre-SR-71 days, to an M-12 (the drone-carrier variant of the A-12). However, the problems are felt to be manageable, last I heard: Lockheed was saying "feasible" when NASA Dryden talked to them about carrying HALO up to Mach 3 on SR-71-back. -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Fri, 11 Dec 92 13:49:51 GMT From: Dean Adams Subject: Aurora Newsgroups: sci.space PHARABOD@FRCPN11.IN2P3.FR writes: >>From Wall Street Journal... >>Magazine Suggests Aircraft Has Flown Mach 8 for Years >Very interesting indeed. Yep. Mostly from Janes... All good stuff. >Now a few comments about this mysterious triangular aircraft: It's not totally a "triangular aircraft". If you look at the drawing with the article, it looks a little more like a NASP-ish vehicle. >1). In the article "Recent Sightings of XB-70-like Aircraft Reinforce >1990 Reports from Edwards Area", AW&ST (August 24, 1992) Right. That would almost certainly be the same craft. >The first sightings (1990-1991) were of a "primarily delta-shaped" >aircraft. Not really... The first reported Aurora design ideas were of a smaller "almond" shaped sort of vehicle, also called the "pulser". The more recent reports seem to be of something much larger. >Only in the two last sightings (1992) were reported a "narrow >fuselage" and/or a "forward wing or canard". Maybe these two last >sightings can be discarded WHAT?? The previous reports were based on "design concepts", these are much more direct reports. There is no logical reason for simply "discarding" such information. >(IMHO, all these sightings are no more convincing than UFO sightings IMHO they are VASTLY more "convincing" that any "aliens". We *know* that the Skunk Works has been working on a high-Mach follow-on recce aircraft. >If they can be discarded, then we are left with reports of "triangular" >aircrafts in the Wall Street Journal and in the AW&ST article. The one that really appears "triangular" would be the Northrop TR-3A. A subsonic counterpart to the F-117A, but totally seperate from Aurora. >My conclusion: maybe Aurora and the "XB-70-like" aircraft are the same >beast, in which case there is no TSTO, only a hypersonic spy plane. The first conclusion could possibly be correct, but I see no basis for confirming/elimiating the TSTO concept at this point... >2). Unknown triangular crafts have been reported over Belgium in >1989-1990-1991, and there have been more than a few sightings: >it has a 82-degrees nose, not far from the 75-degrees reported in the >Wall Street Journal (I know, it depends on perspective). Who knows if there is a connection or not... >However, these crafts could hover silently. And that makes the reports subject to great skepticism. > Could Aurora go at Mach 8 and also hover silently? Seems very unlikely. VERY. >So the Belgian objects were probably not Aurora, maybe just a hoax... but: Probably. >3). In its December 1991 issue, Popular Mechanics (article "America's >New Secret Aircraft") reports, near Edwards AFB, a big triangular object >which, like the Belgian object, can hover silently horizontally and >vertically... 99% of that article consisted of repeating the previous AW&ST report. Then they threw in that one extra report. It did not sound like it was very highly substantiated... >Hence the hypotheses: >a) The USA have really a extraordinary triangular plane, which can >both hover and reach Mach 8. Mach 6-8 is sounding more and more likely, "hovering"... not likely. >b) The USA have a triangular spy plane which goes at Mach 8, The current Aurora concepts do all include a delta planform wing, but just calling it a "triangle" would be a great oversimplification. >and a triangular airship which looks like this plane. Maybe the >airship has been built just in order to confuse people. I see no logic/reason/evidence for such a theory. For one thing that single "airship" report did not sound anything at all like the Aurora designs we have seen. Building such a thing merely to "confuse people" sounds pretty silly to me... >c) Popular Mechanics and AW&ST are no more serious than UFO reviews. Strike Three. :-> Where is the logic there? I can't speak for P.M., but have you ever read AW&ST? It is VERY serious. ------------------------------ Date: 11 Dec 92 16:57:08 GMT From: Henry Spencer Subject: Cassini Undergoes Intensive Design Review Newsgroups: sci.space In article <1992Dec10.232527.643937@locus.com> hayim@locus.com (Hayim Hendeles) writes: >Pardon my asking an ignorant question, but I can't understand why it >should take 7 years to get to Saturn. When Voyager went to Jupiter and >Saturn, it took (if I recall correctly) 4 years and a Jupiter flyby to >make it to Saturn. Here, you are using 4 flybys, and it's taking you 7 >years! I would think that if you were to adjust the launch date so that >Jupiter and Saturn were in the same relative positions as they were in >1977 (when Voyager was launched), you could do the same trick again... Cassini *is* using a Jupiter gravity assist, like Voyager. The main reason it's taking 7 years to Saturn is the same reason it's taking Galileo forever and a day to get to Jupiter: the spacecraft is overweight. With 1950s propulsion technology -- which is what we're still using for these missions!! -- there is a limit to how much mass we can get to Jupiter on a direct trajectory a la Voyager. Galileo and Cassini are simply too heavy, so they have to play ping-pong around the inner solar system for years first to get up enough speed to reach Jupiter. -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 11 Dec 92 17:22:36 GMT From: Henry Spencer Subject: DC-1 passenger service Newsgroups: sci.space In article jbh55289@uxa.cso.uiuc.edu (Josh 'K' Hopkins) writes: >On the subject of jet-lag, I think you may have made a few incorrect >assumptions. I use time on the plane to at least start to adapt, or at least >I think I do. I can go to sleep a little early or a little later. If I fly >aboard TranSpace airlines I won't have time to sleep - I'll just have to deal >with it when I get there. Or before you leave. Whatever you do to adapt, you can do it better in a comfortable bed in a hotel, or at home, than in an uncomfortable seat on an endless intercontinental flight. There is no practical difference between (a) sitting on your own couch for umpteen hours and then being teleported instantaneously to Paris, and (b) flying to Paris, except that (b) is less comfortable. I speak as someone who's twice spent Christmas in Australia: a 22-hour flight with an 8-hour time difference. Jet lag wasn't a problem -- I adjusted my schedule before leaving (it helped considerably that a night owl in Toronto and an early bird in Australia are on almost exactly the same time!) -- but spending nearly a full day on an airliner I really could have done without. >>(...talking about surface-to-surface travel, not surface-to-space, >>which is a very different market with a proven audience.) > >That was the subject in mind. I agree on space tourism. Do you have any >numbers to post though? I don't know what the numbers were like, but I do know that business was brisk when Society Expeditions was taking bookings for hoped-for Phoenix orbital flights at $50k a head. -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 11 Dec 92 04:22:03 GMT From: Greg Moore Subject: DC vs Shuttle capabilities Newsgroups: sci.space In article <1992Dec10.205338.9475@iti.org> aws@iti.org (Allen W. Sherzer) writes: >In article <1992Dec10.193703.16533@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: > >>From the vague descriptions I've seen, the cargo bay would seem to >>lack elementary things like an air lock. > >True but the doors can open in space. > >>Does that mean that passengers >>would ride up in a spacesuit and debark to a station? > >Depends. Remember how they do payload integration. They provide >standard interfaces and you build to that. If you need an airlock, >just build it so it works with their pallet. > >>That plus the >>short on orbit time seems to mandate an operating space station as >>destination. > >Or satellite deployment/retrieval. > Two notes: 1) Won't teh crew compartment take up part of the cargo bay? 2) Even at your launch costs, retrieval would be hard pressed to be profitable. Also, as for retrieval, the Shuttle has shown that it ain't easy to do. Will a two day on-orbit time be enough? Let's not try to have DC-1 do everything... remember that is where the shuttle went wrong. > Allen > >-- >+---------------------------------------------------------------------------+ >| Allen W. Sherzer | "A great man is one who does nothing but leaves | >| aws@iti.org | nothing undone" | >+----------------------135 DAYS TO FIRST FLIGHT OF DCX----------------------+ ------------------------------ Date: 11 Dec 92 05:03:22 GMT From: "Michael V. Kent" Subject: DC vs Shuttle capabilities Newsgroups: sci.space In article <1992Dec10.151210.21951@iti.org> aws@iti.org (Allen W. Sherzer) writes: >In article kentm@aix.rpi.edu (Michael V. Kent) writes: >>Here's a question that just popped into my head: Would a modified Spacehab >>(note the "h") module fit in the cargo bay of the Delta Clipper? >Why not just make it a module on the space station? I'm thinking more along the lines of modifying it into a man-tended free-flyer. Delta Clipper's projected 2-day on-orbit time is too short for Spacehab work, especially if you have a space station. There are some experiments that would benefit from man-tended operations instead of space-station operations. Mike -- Michael Kent kentm@rpi.edu Flight Test Engineer Tute-Screwed Aero '92 McDonnell Douglas Rensselaer Polytechnic Institute These views are solely those of the author. Apple II Forever !! ------------------------------ Date: 11 Dec 92 14:18:58 GMT From: "Allen W. Sherzer" Subject: DC vs Shuttle capabilities Newsgroups: sci.space In article strider@clotho.acm.rpi.edu (Greg Moore) writes: > 1) Won't teh crew compartment take up part of the cargo bay? Of course. On the other hand the standard interface which makes you do this reduces integration time which keeps flight rate up and costs down. > 2) Even at your launch costs, retrieval would be hard pressed >to be profitable. In the short run, no. At say, 10M per flight it would be profitable to launch a satellite and then bring back another. A new satellite costs maybe $150M so it would get about $75M used. Spending $5M to get a $75M satellits should be worthwhile. In the longer run, you may be right. Plumeting launch costs will cause payload prices to fall since there will be more and cheaper launches plus the opportunity for on site repair. > Also, as for retrieval, the Shuttle has shown that it ain't >easy to do. Will a two day on-orbit time be enough? It may take modifications to the DC. At the very least you need to add a robot arm and an airlock. > Let's not try to have DC-1 do everything... remember that is >where the shuttle went wrong. But let's use it for what we can. The way to bring costs down fast with this concept is to use it. My view is that we use the basic DC as a 'bus' which can be modified in small ways to meet diverse missions. Costs are cut because the same assembly lines are used to make DC1-EOT (Earth orbit transfer), DC1-OMV, and DC1-LM. This makes the basid DC a building block of a more extensive space infrastructure. Allen -- +---------------------------------------------------------------------------+ | Allen W. Sherzer | "A great man is one who does nothing but leaves | | aws@iti.org | nothing undone" | +----------------------134 DAYS TO FIRST FLIGHT OF DCX----------------------+ ------------------------------ Date: 11 Dec 1992 10:22:13 GMT From: Dieter Kreuer Subject: Galileo Update - 12/08/92 Newsgroups: sci.space Did Galileo take any pictures of the lunar eclipse? ----------------------- --------------------------------- Dieter Kreuer ## ======== / dieter@informatik.rwth-aachen.de Lehrstuhl Informatik IV __ /// /# / dieter%informatik.rwth- RWTH Aachen ## /// # # / aachen.de@uunet.uu.net Ahornstr. 55 ## /// ##### /...!informatik.rwth-aachen.de!dieter W-5100 Aachen, Germany ==== # / PHONE: +49 241 80 21413 ------------------------------ Date: Fri, 11 Dec 92 22:07:10 EST From: John Roberts Subject: Hubble's view of the universe -From: zellner@stsci.edu -Subject: Re: Hubble's view of the universe -Date: 11 Dec 92 16:03:04 GMT -Organization: Space Telescope Science Institute -HST _currently_ has a highly stable and computable point-spread-function with -a sharp inner core 0.1 arcsecond in diameter, with the peak intensity confined -to a single pixel of the Planetary Camera (0.04 arcsecond). The effect of -the spherical aberration is essentially to waste light, putting most of the -light in a much larger cob-web pattern. The effect of the WFPC2 and COSTAR -corrective optics will be to put that wasted light back into the central -core. I would be delighted to hear that any ground-based telescope can do -that routinely for faint objects, but it remains to be demonstrated. -Ben Could you please compare the imagers of WFPC and WFPC2? In the HST lecture I recently attended, Dana Mitchell said that WFPC uses 800 x 800 arrays (four at a time?). He said that the new imagers can be operated at a higher temperature, and implied that they have more pixels. I don't know about relative sensitity to light. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 10 Dec 92 19:02:06 GMT From: Bruce Watson Subject: Orbit Question? Newsgroups: sci.space In article <1992Dec9.140423.21030@bnr.uk| agc@bmdhh286.bnr.ca (Alan Carter) writes: |In article <1077@dgaust.dg.oz>, young@spinifex.dg.oz (Philip Young) writes: ||> In article , David.Anderman@ofa123.fidonet.org writes: ||> |> Your polar geosyncronous satellite takes out one equatorial geosynchronous ||> |> satellite every 24 hours as it passes over the equator at 24,000 miles ||> |> altitude..... ||> ||> If you have enough muscle to counteract the rebound, you should be able ||> to collect one every 12 hours (probability proportional to satellite ||> density in GEO). | |Er... Won't it just take out a *maximum* of 2, and in future fly through |the holes it's made? | Good point, but no. A polar (inclination 90 degrees) satellite's orbit plane will not rotate, so the geosynchronous satellites will intersect that plane twice each day. But don't forget that space is big and satellites are small so an actual collision is very unlikely. -- Bruce Watson (wats@scicom) Bulletin 629-49 Item 6700 Extract 75,131 ------------------------------ Date: Fri, 11 Dec 1992 14:17:11 GMT From: Henry Spencer Subject: Saturn V fates Newsgroups: sci.space.shuttle,sci.space In article <1992Dec10.234827.23650@magnus.acs.ohio-state.edu> rroberts@magnus.acs.ohio-state.edu (Ross Allan Roberts) writes: >Isn't there a SaturnV at Huntsville? Which one is this? ... There is a Saturn V *test article* at Huntsville. It is labelled as such. -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Fri, 11 Dec 1992 06:30:40 GMT From: Thomas Genereaux Subject: Scud Missile technology Newsgroups: sci.space In Lawrence Curcio writes: >Coincidentally, I roomed last year with a Russian Ph.D. physics student >who was in the missile defense command in the army. He claims to have >worked on one of the earlier scuds. He mentioned UDMH and either RFNA of >N2O4, I forget which. I'm active im model rocketry, myself, and he >caught me reviewing nozzle flow one evening. He couldn't believe that >someone would learn this stuff, which he had been forced to study, for >enjoyment. >Anyway, the most amusing part was that he claimed the missile was >programmed through the medium of *paper tape*. It's amazing they got any >of those things off the ground :) The Scud family (and most Soviet missles) use UDMH and RFNA. The stuff is relatively stable, allows for storable fueled missiles, and is generally (for rocket fuel, anyway :-} flames to /dev/null, I wouldn't want to keep it around the house...) benign. Further, it has the nice property of being hypergolic - just start the pumps, and stand back. FWIW - we programmed *our* missiles with mylarized paper tape well into the '80's. Tom G. ------------------------------ Date: Fri, 11 Dec 1992 23:27:33 -0500 From: Lawrence Curcio Subject: Scud Missile technology Newsgroups: sci.space My, I do seem to have a talent for getting people all animated. It happens that I remember paper tape quite well (though not in an aerospace context or even a mylarized context), and none of my memories suggest reliability. And I'm not that hard to please either. I *LIKED* current loop ;) But hey fellas! Can't we still be friends an' all? -Larry (I'm friendly! See! Look! I'm smiling! :) :) :) Curcio ------------------------------ Date: 11 Dec 92 04:10:30 GMT From: Greg Moore Subject: Scuttle replacement Newsgroups: sci.space In article henry@zoo.toronto.edu (Henry Spencer) writes: > >Myrabo's designs, while interesting, hardly qualify as things that are >likely to fly in the next ten years. (The ones I've seen, anyway.) >He's working on third- or fourth-generation laser-launcher techniques, >futuristic research with no immediate practical relevance. > Yes and no. I know they've done mock-ups and were planning on doing partial tests of the engine. So tehy are bending some metal. However, the engine design is fairly advanced. It is a multistage engine in the sense that it operates over a wide range of speeds and atmospheric density. I think the biggest hold up is going to be laser power. Even with SDI, the lasers just aren't there yet. I think Kare may reach orbit first. >What little was being spent on laser launchers that could actually be >built in the near term, things that might actually be useful soon, was >not NASA money. (Past tense used advisedly -- last I heard, the current >funding for laser-launcher work is zero.) > I don't know about this... -- >"God willing... we shall return." | Henry Spencer @ U of Toronto Zoology > -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Fri, 11 Dec 1992 04:05:49 GMT From: Greg Moore Subject: Trees in space... Newsgroups: sci.space In article balesej@ucunix.san.uc.edu (Eric J Bales) writes: >I posted this after having a thought on another group, but no one there >could find any information on it... > >How would a tree grow in zero-g's? I mean, if you take a tree enclose >it in a bubble of some sort, with the roots in one half and the trunk >and branches in another half, what would it look like after a couple >years? Air wouldn't be moving except what little was necessary to keep >it fresh, and the roots would be provided with nutrients. (So, please >don't see read Niven's The Integral Trees, as this is a totally different >situation! :-)) > >2. Would it grow any different in free-fall as opposed to zero-g's? It >seems to me it would not, but I don't know for sure... > Check out some work that Freeman Dyson did. He proposed genectically altering tress so that moiture loss could be controlled and then planting them on comets. (Hey Nick, have I got a job for you! :-) Also, for a good read, check out "The Starship and the Canoe" a biography of both Freeman Dyson and his son Chris. Talks about Freeman's work on Daedelus. >-- >balesej@ucunix.san.uc.edu - atreis@tso.uc.edu -Eric Bales- >ebales@ddt.eng.uc.edu - at098@Cleveland.Freenet.Edu > -The second dolphin- >Dolphins. Soon you will be one of us, and then you will understand. ------------------------------ End of Space Digest Volume 15 : Issue 536 ------------------------------