Date: Sat, 12 Dec 92 05:03:43 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #533 To: Space Digest Readers Precedence: bulk Space Digest Sat, 12 Dec 92 Volume 15 : Issue 533 Today's Topics: absolutely, positively overnight (6 msgs) DC vs Shuttle capabilities (2 msgs) Freeman Dyson biographies... Saturn V fates Scud Missile technology Terminal Velocity of DCX? (was Re: Shuttle ...) (2 msgs) WFPC-2 Will Magnify Hubble's Views of the Universe 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: 10 Dec 1992 20:35:12 GMT From: Anthony J Stieber Subject: absolutely, positively overnight Newsgroups: sci.space In article steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes: >I hate to raise this, but are there ICBM proliferation concerns >over open marketing of DCs? After all, it should have O(100 ton) >payload for IRBM ranges and multiton payload for ICBM ranges >and it can be arranged to come down hypersonically with what 1200 ft >targetting accuracy? Wouldn't it get real expensive real quick to use a billion dollar spacecraft as a dumb throw away ballistic missile? Although a DC-1 could certainly make a real nifty hypersonic ballistic bomber, I haven't heard of any studies on releasing munitions at hypersonic velocities. If it didn't release munitions up high enough, a DC might end up landing too close to ground zero. Of course, nearly any aircraft can be used as a bomber. By the way what is the projected cost for a DC-X' or DC-1? I wish we didn't have to get information in bits and pieces. -- <-:(= Anthony Stieber anthony@csd4.csd.uwm.edu uwm!uwmcsd4!anthony ------------------------------ Date: Thu, 10 Dec 1992 20:58:11 GMT From: "Allen W. Sherzer" Subject: absolutely, positively overnight Newsgroups: sci.space In article <1g89m0INN578@uwm.edu> anthony@csd4.csd.uwm.edu (Anthony J Stieber) writes: >By the way what is the projected cost for a DC-X' or DC-1? A DC-1 could cost anywhere from $250M each to about $1B each (ROM). It is important to note that the difference between these prices is amortization of development costs. Slight increases in demand can produce far larger decreases in cost. >I wish >we didn't have to get information in bits and pieces. I'm doing my best. :-) 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: 10 Dec 92 13:54:13 From: Steinn Sigurdsson Subject: absolutely, positively overnight Newsgroups: sci.space In article <1g89m0INN578@uwm.edu> anthony@csd4.csd.uwm.edu (Anthony J Stieber) writes: In article steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes: >I hate to raise this, but are there ICBM proliferation concerns >over open marketing of DCs? After all, it should have O(100 ton) >payload for IRBM ranges and multiton payload for ICBM ranges >and it can be arranged to come down hypersonically with what 1200 ft >targetting accuracy? Wouldn't it get real expensive real quick to use a billion dollar spacecraft as a dumb throw away ballistic missile? Although a DC-1 could certainly make a real nifty hypersonic ballistic bomber, I haven't heard of any studies on releasing munitions at hypersonic velocities. If it didn't release munitions up high enough, a DC might end up landing too close to ground zero. If you've spent $100 billion on nuclear technology a billion dollar throwaway ICBM is a small marginal extra. And unfortunately I can think of several scenarios where a uninterceptable one off delivery vehicle would just the item required... Of course, nearly any aircraft can be used as a bomber. Yup, but DCs would probably be lousy. As you noted hypersonic release is non-trivial. Hence use it as an unmanned ICBM (hell, make it manned, I could imagine some volunteers - although they might make lousy pilots by definition) - but just set if for an airburst using the altimeter... hell, if Gary is right all they'd have to do is hover over downtown for a few seconds ;-) | Steinn Sigurdsson |I saw two shooting stars last night | | Lick Observatory |I wished on them but they were only satellites | | steinly@lick.ucsc.edu |Is it wrong to wish on space hardware? | | "standard disclaimer" |I wish, I wish, I wish you'd care - B.B. 1983 | ------------------------------ Date: Thu, 10 Dec 1992 21:48:29 GMT From: Henry Spencer Subject: absolutely, positively overnight Newsgroups: sci.space In article <1g89m0INN578@uwm.edu> anthony@csd4.csd.uwm.edu (Anthony J Stieber) writes: >By the way what is the projected cost for a DC-X' or DC-1? I doubt that anyone has a good handle on DC-1 purchase prices yet. There is no *fundamental* reason why it should be more expensive than a small airliner (say $25M). With the exception of the thermal protection, the materials are things that are already being used in that market or are about to enter it. The vehicle is not overly large. The avionics are not far from commercial-aircraft stuff. The engines are probably grossly expensive by aircraft standards because of small production volume, but one would hope that a substantial DC-1 production run would help that. Initial price maybe that of a 747 ($150M)? Seems a plausible guess. -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Thu, 10 Dec 1992 21:55:44 GMT From: Henry Spencer Subject: absolutely, positively overnight Newsgroups: sci.space In article steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes: >I hate to raise this, but are there ICBM proliferation concerns >over open marketing of DCs? After all, it should have O(100 ton) >payload for IRBM ranges and multiton payload for ICBM ranges >and it can be arranged to come down hypersonically with what 1200 ft >targetting accuracy? It doesn't *quite* have the right capabilities, because it's not capable of hypersonic descent to low altitude. Spacecraft and warheads have very different thermal protection. Spacecraft do almost all their decelerating at very high altitude in very thin air, where thermal loads are manageable. Warheads want to keep as much velocity as possible, and can afford to just postpone the thermal loads because after detonation it won't matter. However, I imagine you could take it up into a suborbital hop, kick a few warheads out the door, and then do another burn so you land somewhere else. It probably will be subject to missile-proliferation rules, at least at the start. If spaceships start becoming common, then limited missile defences are probably going to become common too. (They have to anyway, because building a V-2 equivalent is no longer that difficult.) -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Thu, 10 Dec 92 22:58:26 GMT From: Doug Mohney Subject: absolutely, positively overnight Newsgroups: sci.space In article <1g89m0INN578@uwm.edu>, anthony@csd4.csd.uwm.edu (Anthony J Stieber) writes: > Although a DC-1 >could certainly make a real nifty hypersonic ballistic bomber, I >haven't heard of any studies on releasing munitions at hypersonic >velocities. You shouldn't. :-). But they didn't call the SR-71 the Recon-STRIKE-71 before LBJ's mangling for nothing. Play in the intelluctual sandbox of Usenet -- > SYSMGR@CADLAB.ENG.UMD.EDU < -- ------------------------------ Date: Thu, 10 Dec 1992 20:53:38 GMT From: "Allen W. Sherzer" Subject: DC vs Shuttle capabilities Newsgroups: sci.space 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. 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: 10 Dec 92 22:13:12 GMT From: Henry Spencer Subject: DC vs Shuttle capabilities Newsgroups: sci.space In article <1992Dec10.193703.16533@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >>Large payloads can go up in pieces for in-orbit assembly. In fact, if >>you believe Fairchild's old Leasecraft study, this approach is superior... > >Yeah, but I also remember how much harder in space assembly has turned >out to be than was originally expected. Hopefully they'll get better >at it with experience... Note also: in-space assembly so far has been done in spacesuits, which is one of the big obstacles. Doing it in a pressurized hangar ought to be a lot easier. (Actually, there are a few operations for which you'd prefer to work in spacesuits. If you will insist on using vile gunk like hydrazine as fuel, fuelling [say] Cassini ought to be considerably safer in vacuum with the fuelling crew in spacesuits.) >... Anything >much beyond simple mating of standard modules in space is probably >stretching things too far... I'm inclined to agree. On-ground labor is still quite a bit cheaper than in-space labor, even with very favorable assumptions about DC-1 or whatever. Plugging the boxes together, okay. Emergency troubleshooting, okay. But the birds will still be built on the ground. >>DC-1's cargo bay will easily hold more crew than the shuttle can carry. > >From the vague descriptions I've seen, the cargo bay would seem to >lack elementary things like an air lock. Does that mean that passengers >would ride up in a spacesuit and debark to a station? The cargo bay of the vehicle proper is just a box with doors; I don't think it's even pressurized. You pop a prefabricated crew compartment, which can have airlocks etc., into it. Personally, I think riding up in spacesuits is not a ridiculous idea, given that you expect to reach a pressurized destination in short order. But it's less than ideal for a number of reasons, not least being that current spacesuits are heavy. >That plus the >short on orbit time seems to mandate an operating space station as >destination. Now I like space stations, but we don't have one yet. >Nor are we likely to have a functional one in the short timeframe >until DC-1 is projected to be operational... We should be able to have one very shortly after DC-1s become available. There is no particular difficulty in building a space station within a year or two, if transport is cheap and you deal with a construction company rather than an aerospace contractor. (The one from the a.c. will weigh much less, if you don't count the paperwork, but will cost a lot more and take rather longer.) The incredible cost and schedule of SSF are because (a) it is THE space station rather than A space station and (b) every gram is precious. >... With the crew >cabin in the middle, docking with a station would seem very difficult. Not really. The shuttle's station docking point is also in its middle. You just approach sideways, so you can see what you're doing. >That's an interesting question anyway. How is docking with Freedom >supposed to be handled? Unless it's changed since I saw it described, basically the shuttle gets close, and then the station's arm reaches out, grabs it, and moves it into position. For some of the early assembly, it'll be vice-versa with the shuttle arm doing the work, but the shuttle arm isn't strong enough to move the whole shuttle around routinely. This makes considerable sense, in general. For routine use, you want a docking method that tolerates considerable error. Getting within the "capture volume" of an arm is a lot less fussy than making the docking yourself. -- "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 13:56:11 -0600 From: pgf@srl03.cacs.usl.edu (Phil G. Fraering) Subject: Freeman Dyson biographies... \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. I've read it. It's passable in most parts, but altogether it's horrible. The author feels so much more morally superior to both Dysons but apparently especially to Freeman Dyson himself. I was also disturbed by the general attitude its author seemed to have towards people working in the physical sciences and/or engineering. If you want to read a good biography of Dyson, that is fair and still (IMHO) doesn't pull any punches, try the biographical parts scattered through his own works. They're better written, more fun, and also have a lot of good ideas, _firsthand_. -- Phil Fraering "...drag them, kicking and screaming, into the Century of the Fruitbat." <<- Terry Pratchett, _Reaper Man_ PGP key available if and when I ever get around to compiling PGP... ------------------------------ Date: 10 Dec 92 23:48:27 GMT From: Ross Allan Roberts Subject: Saturn V fates Newsgroups: sci.space.shuttle,sci.space A question to cause further confusion... ;-) Isn't there a SaturnV at Huntsville? Which one is this? I haven't seen any mention of this one... I have a book simply entitled 'Apollo' that is real good at explaining the missions and planning that went into the Apollo project. Unfortunately, I just lent it to someone, so I have no other info about it at the moment. When I get it back, I'll post enough info you could find it at a library. It's a real good book. Looks at the missions from more of the control room prespective, discusses design obstcles, and special stuff such as the fire, 12's lightning strike, and of course 13. ############################################################################# #Ross Roberts (rroberts@magnus.acs.ohio-state.edu)|'85 IT200, '81 MX100 # #DoD#0340, still patiently awaiting the 6ooF2... |'88 YFM350 Warrior # #---------------------4-stroke good, 2-stroke gooder!---------------------- # Friends don't let friends drive Suzuki's ############################################################################# ------------------------------ Date: Thu, 10 Dec 1992 20:51:23 GMT From: George Wm Turner Subject: Scud Missile technology Newsgroups: sci.space In article , 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. > [deleted] >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 :) 12 years ago, our military forces used paper tape to program some of its strategic systems. its a medium that is radiation hardened, holds up well under field conditions, and is easy to use by the crews. the actual programming is done somewhere else; the paper tape only loads the program into the system. george wm turner turner@bigbang.astro.indiana.edu (812) 855-6911 ------------------------------ Date: Thu, 10 Dec 1992 21:00:08 GMT From: "Edward V. Wright" Subject: Terminal Velocity of DCX? (was Re: Shuttle ...) Newsgroups: sci.space In <1992Dec9.133030.6288@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes: >An SSTO has to haul all of it's engine and structure mass to orbit so >these have to be lighter than a staged rocket that can discard engines >and structure along the way. This is inherent in SSTO design. So a >staged rocket can be made to have lower stresses than a SSTO for the >same payload. Except that there is absolutely no relationship between the size (thrust) of an engine and the "stress" on it. Robert Truax has designed very large engines for his Sea Dragon (millions of pounds thurst) with extremely *low* chamber pressures. Faulty analogies to race cars not withstanding. >The wings impose a mass penalty, >but that's offset by not having to carry landing fuel and it's tankage >for VTOL operation. No, it's not. The mass of propellent required for a vertical landing is much less than the weight of the wings. The only way you can possibly come out ahead is if you use the wings for lift on both takeoff and landing. ------------------------------ Date: Thu, 10 Dec 1992 19:51:38 GMT From: Gary Coffman Subject: Terminal Velocity of DCX? (was Re: Shuttle ...) Newsgroups: sci.space In article ewright@convex.com (Edward V. Wright) writes: >In <1992Dec5.165219.18302@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes: > > >>Look, I'm not trying to be dense here, but in circuit design we know >>that the more parts you have in a circuit, and the harder you push >>them, the more likely you'll have a failure. So you try to simplify, >>and beef up what remains to stand the maximum expected stress. > >Well, obviously, then, you don't know anything fault-tolerant circuits, >which increase the number of parts in order to reduce the probability >of a failure. Aircraft engineers were designing fault-tolerant and >fail-safe systems before anyone even heard of electronic engineers. And electrical engineers were building and operating multi-megawatt power systems long before aircraft ever left the drawing board. We know something about reliability engineering too. We like things simple and robust. Every safety critical circuit has a separate backup, usually using a different design that is unlikely to share common failure points. Simple redundancy is all fine and good, but can lead to redundant failures. Gary ------------------------------ Date: Fri, 11 Dec 1992 05:30:31 GMT From: Ron Baalke Subject: WFPC-2 Will Magnify Hubble's Views of the Universe Newsgroups: sci.space,sci.astro From the "JPL Universe" December 4, 1992 JPL's new camera will magnify Hubble's views of the universe By Diane Ainsworth Just weeks ago, the Hubble Space Telescope's all-purpose "eyes" -- known as the Wide Field/Planetary Camera -- captured the most detailed view ever of a galaxy's core, feeding a suspected black hole in the Virgo cluster about 45 million light years from Earth. "The nucleus is probably the home of a black hole with a mass 10 million times that of our sun," said Dr. Walter Jaffe of the Leiden Observatory in the Netherlands, whose findings were published in the Astrophysical Journal. "This is our best view to date of the immediate surroundings of the nucleus of an active galaxy." While the performance of Hubble's Wide Field/Planetary Camera-1 (WF/PC-1) has been hampered by a flaw in the curvature of the telescope's primary mirror, the camera has nonetheless produced some of the most awe-inspiring photographs of planets, galaxies and exploding supernova ever taken. Now JPL's new second-generation Wide Field/Planetary Camera (WF/PC-2) -- scheduled for launch as part of the Hubble Space Telescope's servicing mission next December -- is in final assembly and promises even more spectacular views of distant galaxies in the universe. The new camera has been designed to correct the optical flaw in the Space Telescope's 95-inch (2.4-meter or 8-foot) diameter primary mirror. After installation, WF/PC-2, along with a second instrument -- COSTAR, the Corrective Optics Space Telescope Axial Replacement -- will restore the Hubble Telescope to its original capabilities of imaging fine detail with high angular resolution, photographing star clusters, detecting very faint stars, distant galaxies and objects in the ultraviolet. An innovative approach to correct the error in the primary mirror was incorporated in the design of the new secondary mirrors of the Wide Field/Planetary Camera relay optics, said Larry Simmons, WF/PC-2 program manager at JPL. "The WF/PC-2 incorporates optics that will internally refocus the beam of incoming light from Hubble," he said. "We corrected for the error in the curvature of the primary mirror by creating an error of equal and opposite magnitude on the surfaces of our WF/PC-2 relay optics. When the images reach the camera's charge-coupled detectors (CCDs), the error will be reversed and completely cancelled out." The Wide Field/Planetary Camera-2 actually consists of four camera systems -- three wide-field cameras and one planetary camera. The wide-field cameras provide extraordinary sensitivity for the detection of star clusters and distant galaxies, while the planetary camera performs high-resolution studies of individual objects, including planets and their moons, nearby galaxies and other stellar objects. As light enters the Hubble Space Telescope, it is bent at a 90-degree angle by a "pick-off" mirror and aimed into the Wide Field/Planetary Camera. Design modifications in the new WF/PC call for an adjustable pick-off mirror that ground technicians will be able to tilt to align the light beam entering the camera. "The alignment of the pick-off mirror is critical to correcting images," Simmons said. The light beam passes through one of 48 filters before a pyramid mirror inside the camera splits the light into four quadrants. Each of the four quadrants of light is relayed by tiny, nickel-size relay mirrors -- the mirrors that JPL modified to correct for the error in the telescope's primary mirror -- to a separate detector called a charge-coupled device (CCD). CCDs collect light in the same way that film collects light in a camera, but with much greater sensitivity. "The corrected images are formed on the CCD sensors," Simmons said. "The CCDs we are using in the new camera will have greater sensitivity and will allow the camera to see from the ultraviolet to the infrared." The new Wide Field/Planetary Camera and the COSTAR axial replacement instrument will restore Hubble's imaging performance to nearly 100 percent of the original specifications. Currently, the telescope is able to focus only 10 to 15 percent of the light it receives within a diameter of 0.2 arc-second. Its original performance goal was to focus 70 percent of the light received. The telescope was designed to provide three basic capabilities: high angular resolution -- the ability to image fine detail; ultraviolet performance -- photographing ultraviolet images and spectra; and high sensitivity -- the ability to detect very faint stellar objects. With its corrective optics, scientists expect the telescope will be able to provide the highest sensitivity to detect objects 10 times fainter than those visible from Earth-based telescopes, with about 10 times greater spatial resolution. ### ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | The 3 things that children /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | find the most fascinating: |_____|/ |_|/ |_____|/ | space, dinosaurs and ghosts. ------------------------------ End of Space Digest Volume 15 : Issue 533 ------------------------------