Date: Tue, 9 Mar 93 10:05:32 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #291 To: Space Digest Readers Precedence: bulk Space Digest Tue, 9 Mar 93 Volume 16 : Issue 291 Today's Topics: *** The Shuttles 5 computers. INFORMATION 20 kHz Power Supplies "blowing up"! a shining wit Aurora Update (2 msgs) a whining shit Cyrano and the Ark (was Re: Ark Discovered on the Moon) Gaspra Animation NASP (was Re: Canadian SS Pluto Fast Flyby post-flyby fate Proposed Jupiter f/c/b mission SSF Resupply (Was Re: Nobody cares about Fred?) The courage of anonymity (2 msgs) Water resupply for SSF (?) (2 msgs) 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: Mon, 8 Mar 1993 13:30:56 GMT From: Luke Plaizier Subject: *** The Shuttles 5 computers. INFORMATION Newsgroups: sci.space I am presently embarking on a year-long project to develop a fault tolerant computer system by way of having 3 computers in a Triple mode Redundant setup. I would like to find some information on the US Space Shuttle computer system which has a Triple Mode Redundand system with 2 backup spares (At least that's the way I've heard it before.) This is for the purpose of a display and seminar which will provide 'glossy posters' for people to look at while I continue the real work at hand. This request is for information of any kind - electronic or otherwise - that may help in formulating a justifiable tie between my project and the computer system of the shuttle. Please forward any information you have and are willing to release to me at this email address. I thank you for listening to my plea for assistance and hope you live and proper. Ad Astra Luke Plaizier University of Newcastle Australia ------------------------------ Date: 8 Mar 1993 10:19 EST From: "David B. Mckissock" Subject: 20 kHz Power Supplies "blowing up"! Newsgroups: sci.space In article <1n4441INN47i@access.digex.com>, prb@access.digex.com (Pat) writes... > > Before they killed the 20 kHz power bus, the main power > supply design they had approved and were designed to use > had a single fault failure mode that was explosive in > nature. This is inside the Pressure vessel. The reaction > of Management to this problem was "so what, no astronauts > will be endangered, this will never fly anyway" Balderdash. I was personally involved in the trade studies performed at WP-04 over the power system distribution frequency for SSF, and nobody in the program ever said the power supplies were single fault tolerant and would explode. To the contrary, 20 kHz was *safer* than DC, because faults could be isolated faster. Also, the scenario you describe "single fault failure mode" would violate several SSF requirements in SSP 30000, the SSF program requirements document. The EPS functions required for station survival shall be single-faulure tolerant with no degradation. Identified hazards which are evaluated to be critical shall be controlled such that no single failure or single operator error can result in the hazardous event. Finally, concerning the supposed management statement of "so what, this will never fly anyway", I have been in this program for a decade, and I have never heard an SSF manager ignore a potential hazard with the excuse that the vehicle probably won't fly. Folks on sci.space love to speculate that SSF managers are a bunch of idiots who really don't care about the success or failure of SSF. My experience with SSF managers (including the Level I program manager Dick Kohrs, Level II managers Moorehead, Bensimon, Cox, and *ALL* of the WP-04 managers) is that they are very concerned with the success of SSF. ------------------------------ Date: Mon, 8 Mar 1993 16:32:40 GMT From: Tim Pierce Subject: a shining wit Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space In article <1993Mar7.213341.29565@fuug.fi> an8785@anon.penet.fi writes: >rsk@gynko.circ.upenn.edu (Rich Kulawiec) says, in part: > >>This is ludicrous. If you do not have the courage of your own convictions, >>and are not willing to back those convictions up by using your own name, >>why should anyone pay the slightest attention to you? (I certainly won't) >>Either you have the guts to back up what you say, or you don't; and if you >>don't, then you should probably just be quiet. > >Right. So -- Anne Frank should have kept her kvetching trap shut, right, >right, Mr. Kulawiec? I believe you owe the readers of soc.culture.jewish an apology for such an insulting comparison to Anne Frank. -- ____ Tim Pierce / You never fuck me \ / twpierce@unix.amherst.edu / and I always \/ (BITnet: TWPIERCE@AMHERST) / have to drive. ------------------------------ Date: Mon, 8 Mar 93 13:24:19 GMT From: Dean Adams Subject: Aurora Update Newsgroups: sci.space prb@access.digex.com (Pat) writes: >> Designed and built at Lockheed Skunkworks in Burbank Ca. >Reasonable. Yup. >>|- operational altitude: 100,000 to 150,000 ft >100,000 I can see, 150, would have to be some sort of ballistic shot. Yea, 150K sounds a little too high. >|- 25 operational from tonapah Base Area 30 in Nevada >Grossly exagerated. More than likely. It also would have been operating from Groom Lake, not Tonapah... >I don't think there were ever more then 12 SR-71s >operational, samething with U-2s. I think there were more than that. After all, 100 U-2/TR-1s were built. >if this thing is what it's cracked up to be, you wouldn't need >more then 2-3 in say 4 bases worldwide. I'm sure they would NOT be in "4 bases". The SR-71 only operated from two primary foreign bases. I doubt an "Aurora" would have ANY. >from nevada, you get to spy on panama and nicaragua, but we overfly >them with TR-1's and RF-14s From Nevada, a *Mach 6* vehicle could go just about anywhere... >Look at the old U-2 ops bases, or SR-71 bases. Scotland, turkey, >pakistan, Nevada, Japan, Korea, Norway? The places you want to see >are not in the western hemisphere. The place we want to see is Groom Lake, NV! :-> FYI, the SR-71 Detachment bases were Mildenhall, UK and Kadena, Japan. ------------------------------ Date: Mon, 08 Mar 93 16:15:23 MET From: PHARABOD@FRCPN11.IN2P3.FR Subject: Aurora Update >|- funding in 1985: $2.3 billion > > 2.3 billion/year, over a 10 year program with funding >variation of 50%, i can see. ... [stuff deleted] ... >Pat (7 Mar 1993 14:58:13 -0500) 2.3 billion/year is not very different from the price of the B-2 program, as it was scheduled in the mid-80s: $ 36.6 billion, beginning a little after 1980 (?), completion 1995 ("B-2 Peak Production Delays Drive Up Program Costs", by Bruce A. Smith, AW&ST, July 24, 1989). Could Aurora be the B-2 ? An indication in favor this hypothesis can be found in what said the Pentagon (could it be that they don't always lie ?): NEW DAWN FOR AURORA, by Russ Britt, Los Angeles Daily News, May 17, 1992: " .... Aviation enthusiasts and analysts have mused over the plane's existence ever since a line item inadvertently appeared in a 1985 Pentagon budget under the reconnaissance aircraft category with the code name Aurora. Pentagon officials claimed it was a reference to the B-2 stealth bomber, which was still secret at the time." J. Pharabod ------------------------------ Date: Mon, 8 Mar 1993 16:42:43 GMT From: Ken Garrido Subject: a whining shit Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space jmaynard@nyx.cs.du.edu (Jay Maynard) writes: >>Right. So -- Anne Frank should have kept her kvetching trap shut, right, >>right, Mr. Kulawiec? >This comparison is one of the most odious I've seen in a long time. Anne Frank >was at danger of her life. You are not. Excuse me, but what does Anne Frank have to do with anonyminouty (sp)? As I understand it, she was writing a personal journal, not submitting articles to the Times-Herald, and she was long dead by the time anyone else read it. So what are you two talking about ? >-- >Jay Maynard, EMT-P, K5ZC, PP-ASEL | Never ascribe to malice that which can >jmaynard@oac.hsc.uth.tmc.edu | adequately be explained by stupidity. > "Support your local medical examiner - die strangely." -- Blake Bowers -- For just a minute there, I was dreaming/for just a minute, it was all so real For just a minute, she was standing there with me... Ken Garrido keng@tunfaire.den.mmc.com Martin Marietta Aerospace ------------------------------ Date: 8 Mar 93 10:57:10 -0600 From: Bill Higgins-- Beam Jockey Subject: Cyrano and the Ark (was Re: Ark Discovered on the Moon) Newsgroups: sci.space,sci.archaeology I apologize for messing up my previous attempt to post this on Friday... Let's try again. In article <1993Mar5.083819.501@news.uwyo.edu>, rtravsky@news.uwyo.edu (Rich Travsky) writes: > The following showed up on the sci.archaeology group. The article speaks > for itself, as further words can hardly do it justice... [He then quotes Eugene Powell (gpowell@ent1.ent.ncsu.edu), in an article that relates to the recent Noah's Ark controversy swirling across sci.archaeology, sci.skeptic, talk.origins, and who knows where else... a couple of Sundays ago a pseudoscientific documentary about finding the Ark appeared on CBS, the network Walter Cronkite and Ed Murrow used to work for. The rest of the quoted material is Powell's:] > It seems IYF TV, a new station on the upper reaches > of the dial, will broadcast a story from Archaicology Magazine about > half of the famous boat found (you won't believe this) on the moon! [...] Well, now, you may think that Eugene Powell is pulling your leg, but wait! I have more evidence! Take a look at Cyrano de Bergerac's (1619-1655) famous book, *Historie Comique des Etats et Empires de la Lune*, often packaged with its sequel *Historie Comique des Etats et Empires du Soleil*. Being French-impaired, I've got Richard Aldington's 1962 translation from Orion Press, *Voyages to the Moon and Sun*. These stories are often cited in histories of rocketry and of science fiction, because in proposing many methods of ascending to the Sun and the Moon, Cyrano anticipated (in a loose sense) a few modern devices. The books were published posthumously, but I'd guess the events described in them took place in the 1630s or 1640s. Arriving upon the Moon, Cyrano discovered the Garden of Eden and met the prophet Elijah. Apparently quite a few characters from the Bible made their way to the Moon by various means. One of them was Achab, a daughter of Noah. As the rain fell and the Flood rose higher and higher, it eventually reached the level of the Moon. Achab left the Ark in a small boat and grounded it on the lunar surface. Is it possible that the boat-like fragments Powell speaks of are the remains of Achab's boat, rather than the Ark itself? The House Telecommunications Subcommittee | has scheduled a hearing on the issue for | Bill Higgins next Wednesday, featuring advocates of | Fermilab tougher regulation as well as Shari | higgins@fnal.fnal.gov Lewis, host of a children's show on public | higgins@fnal.bitnet television, and her sock puppet Lamb Chop. --*N.Y. Times*, 4 Mar 93, p. A9 ------------------------------ Date: Mon, 8 Mar 1993 10:14:51 GMT From: Tero Sand Subject: Gaspra Animation Newsgroups: sci.space,sci.astro,alt.sci.planetary In article <7MAR199320200059@kelvin.jpl.nasa.gov> baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes: >will work with CGA - I'm surprised anybody is still using CGA. There is Ah, I don't have choice in the matter (for now) - my computer is an Apple IIGS*, and in it I have an IBM co-processor card, and it only emulates CGA. * Never mind. :-) Tero Sand -- EMail: cust_ts@cc.helsinki.fi or custts@cc.helsinki.fi "I feel most ministers who claim they've heard God's voice are eating too much pizza before they go to bed at night, and it's really an intestinal disorder, not a revelation." - Reverend Jerry Falwell ------------------------------ Date: Mon, 8 Mar 1993 13:56:05 GMT From: "Allen W. Sherzer" Subject: NASP (was Re: Canadian SS Newsgroups: sci.space In article <1993Mar4.232811.21483@ee.ubc.ca> davem@ee.ubc.ca (Dave Michelson) writes: >I'm amazed that the NASP was even funded. Back in 1978, the American Institute >of Aeronautics (Technical Committee on Space Systems) concluded that: > "Rapidly evolving vehicle concepts and technologies point to the feasibility > of fully reusable Earth-to-orbit vehicles, including single-stage-to-orbit > (SSTO) transports, by the early 1990's.... I don't think it was ignored as much as you think. There have been a number of classified programs working on SSTO over the past 12 years. Two in particular called Science Dawn and Have Region produced detailed designs and even prototype structures. Let's hope DC gets funded. Allen -- +---------------------------------------------------------------------------+ | Allen W. Sherzer | "A great man is one who does nothing but leaves | | aws@iti.org | nothing undone" | +----------------------990 DAYS TO FIRST FLIGHT OF DCX----------------------+ ------------------------------ Date: 8 Mar 93 13:29:36 GMT From: Gregory P Dubois Subject: Pluto Fast Flyby post-flyby fate Newsgroups: sci.space Pioneers 10 and 11, and Voyagers 1 and 2, in view of their solar system escape trajectories, each carried some form of message theoretically intended for the benefit of some extra-solar civilization that might one day locate and salvage the spacecraft. Leaving aside all the questions which can be asked about the past efforts, given that the Pluto Fast Flyby mission currently under consideration will presumably be on an escape trajectory, does anyone know if there has been any serious consideration of affixing some form of message to the two spacecraft? Given the weight restrictions, presumably something either much more modest or much more weight-efficient than the Voyager record would be necessary. I would be very sympathetic to claims that every gram of payload should be used for science, but it seems nonetheless an obvious question. On a more serious note: given the limited complement of instruments and the desire to keep operating and overall life-cycle costs down, is it envisioned that the PFF spacecraft will do any science after the flybys? At the very least, I would imagine they could do radio science and participate in, e.g., gravity experiments. Would they be able to say anything about the heliopause, and for how long could we stay in contact? I realize this is all very premature and that there is no stable design yet, but perhaps it would still be interesting to hear some speculations. Gregory Dubois ------------------------------ Date: Mon, 8 Mar 1993 14:09:42 GMT From: gawne@stsci.edu Subject: Proposed Jupiter f/c/b mission Newsgroups: sci.space Last week Bill Higgins wrote: >...you might look at the Discovery Program Workshop report. >A Jupiter mission is pretty hard to do on $150M, but there is one >tricky candidate. I don't know if it counts as a followon by your rules: > % Earth Orbital Ultraviolet Jovian Observer will study >the Jovian system from Earth orbit with a spectroscopic imaging >telescope. Principal Investigator: Paul Feldman, Johns Hopkins >University, Baltimore. Since I've had the pleasure of working with Paul Feldman in the past executing some of his HST proposals, I thought I'd go on and ask him for some more information about this. The following has been extracted from the information packet he put together for the Discovery Workshop on Nov 17, 1992. EARTH ORBITAL UV JOVIAN OBSERVER Investigators: Fran Bagenal, Univ of Colorado Michael J. S. Belton, NOAO A. Lyle Broadfoot, Univ of Arizona John T. Clark, Univ of Michigan Alan Delamere, Ball Aerospace (Technical Lead) Paul D. Feldman, Johns Hopkins Univ (PI) Arthur L. Lane, JPL David Skillman, Goddard SFC Objectives Focused, low-cost mission to study the Jovian system from Earth orbit through ultraviolet (550 - 1750 angstroms) spectroscopy and extrame ultraviolet (EUV) imaging. Investigation of long-term temporal behavior of both Jupiter and the Io plasma torus. Approach Integrated spacecraft and scientific instrument. Utilize state-of-the-art off-the-shelf technology already developed for NASA and DoD missions. No new development. 0.6 meter telescope in HEO (L1 point) [the L1 point is the sunward Lagrange point] Continuous viewing of Jupiter over 8 month period Short time (< 3 years) from project start to launch Single mission objective reduces cost of ground operations Additional solar system science objectives (e.g., comets) possible after end of Jupiter observations Proposed Telescope Optics and Instrumentation Telescope 60 cm diameter Cassegrain f/17 telescope design Normal incidence optics using Silicon Carbide (SiC) coatings to optimize UV signal Pointing Control Focal plane visible light CCD fine error sensor for accurate pointing; selection of imaging or spectroscopy requires no moving parts Science Instrumentation EUV Imager -- Spectral bandwith from 700 to 1450 angstroms. The detector is a 224 x 960 pixel MAMA (Multi-Anode Microchannel plate Array) with a KBr (Potassium Bromide) faceplate, and a pixel size of 25 um = 0.5 arcseconds on the sky. Long-slit Imaging Spectrograph -- Spectral range from 550 to 1750 angstroms. This instrument also uses a 224 x 960 MAMA detector, but with a CsI (Cesium Iodide) faceplate. It utilizes a 300 line per mm toroidal diffraction grating. Spectral resolution is selectable for delta lambda either 2.5 or 10 angstroms. The slit subtends one second of arc width on the sky. The spectrograph has a 40 cm focal length and a f/17 focal ratio. The pixel scale in high resolution mode is 1.25 angstroms per 25 um pixel. As I mentioned above the planned orbit is at the L1 Lagrange point. The mission would be launched aboard a Delta II and would employ one ground station at Goddard Space Flight Center. Data storage would utilize 250 Mbit solid state memory, and there would be one data dump per day. This provides for a minimum of ground support. The spacecraft has a design lifetime of two years, and an expected mission duration of one year. -Bill Gawne, Space Telescope Science Institute "Forgive him, he is a barbarian, who thinks the customs of his tribe are the laws of the universe." - G. J. Caesar ------------------------------ Date: Mon, 8 Mar 1993 13:47:47 GMT From: "Allen W. Sherzer" Subject: SSF Resupply (Was Re: Nobody cares about Fred?) Newsgroups: sci.space In article <1993Mar4.032241.7255@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >That's not true. NASA's budget is around $14 billion. Even the pessimists >grant that Shuttle's operational budget is around $3.5 billion a year. Plus a billion or so on sustaining engineering and NASA overhead. All together we are looking at about $5B a year. >There's dispute over how to account for some of the standing army, but >that includes costs directly associated with Shuttle. But not all costs. There is a lot of bootleg money skimmed off by center managers. For example, at JSC about half of the engineering directorate is working on Shuttle. Yet as near as I can tell, Shuttle money isn't funding these people. >If you look only >at incremental costs, a Shuttle flight costs around $300 million tops, More like $100M. However, this is a rather bogus figure since there are no incrimental flights possible. >perhaps as little as $180 million depending on flight frequency and other >issues. In neither case is Shuttle's budget HALF of NASA's budget. Some estimates which loot at total spending, not just appropriated line items, disagree. Shuttle could be consuming half the NASA budget but NASA accounting is so poor its hard to say. Allen -- +---------------------------------------------------------------------------+ | Allen W. Sherzer | "A great man is one who does nothing but leaves | | aws@iti.org | nothing undone" | +----------------------990 DAYS TO FIRST FLIGHT OF DCX----------------------+ ------------------------------ Date: Sun, 07 Mar 93 00:58:21 EST From: Ben Coleman Subject: The courage of anonymity Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space an8785@anon.penet.fi (8 February 1993) writes: > Yes, it takes more effort to get your mind around anonymous > posts than attributed ones: we get out of the habit of > evaluating arguments without the guiding badges and trappings > of authority accompanying them. Those posters who have > forgotten how to legitimately persuade and, through time and > accreting rank, have relied upon the prestige of their > posting site may well have reason to fear the new order of > things. I'm afraid all you've done for me with this argument is to further persuade me that C. S. Lewis's term "Bulverism" ought to be brought back and dusted off so we'll have an appropriate label for these kinds of argument. Ben +---------------------------------------+---------------------------------+ | Ben Coleman NJ8J | "All that is not eternal is | | Packet: NJ8J@W4QO.#EAL.#ATL.GA.USA.NA | eternally irrelevant." | | Internet: ben@nj8j.atl.ga.us | | | or ben@nj8j.blackwlf.mese.com | C. S. Lewis | +-------------------------------------------------------------------------+ ------------------------------ Date: Mon, 8 Mar 1993 16:00:41 GMT From: Dillon Pyron Subject: The courage of anonymity Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space In article <1993Mar7.004339.4397@fuug.fi>, an8785@anon.penet.fi (8 February 1993) writes: >It's been six weeks now since I posted the original >"Challenger" article to sci.space and sci.astro as a >contribution to the on-going thread reminiscing on the >tragedy. I am still surprised at the intensity of negative >reaction that several posters had to the article and >by association to the concept of anonymous posting. The article was recycled tripe. > >While the usual reader of those newsgroups may be far more >comfortable with the inhuman aspects of space flight -- >metric tons of fuel, pseudoinverse trajectory calculation, >torrs of Oxygen, kilos of payload -- I believe that the >phenomenon of crewed space flight is far more interesting at >the sharp human edge, the sharp edge that cuts a thin bead of >blood into the skin. Then talk about people, about personalities, about the stress and strain of development, testing and operation. Don't talk about crap that was published several years ago, and refuted almost instantly. > >Looking at political issues of funding and priorities as well >as the social consequences of space exploration, many of us >believe that the human angle is far more important, but fluid >and ill-defined, than the technical problems of space travel. >This protean quality of the human issue makes for many of us >a more interesting challenge to understand and integrate >into the whole picture than the relatively more deterministic >mechanical issues. Like I said, then talk about those issues, not crap. > >Sci.space and sci.astro need many more blunt posts centered >on the human theme, even if strong medicine to many readers. > One more time ... >As far as anonymous postings in general, the threats of >personal violence that the Challenger post unearthed, for me, >more than confirmed my decision to use it. The contrary >arguments that legitimate science will be swamped with >anonymous bacchanals is simply not happening, even though >over 20,000 people now have used the Finnish anon service. >The newsgroups have approximately the same mix of surplusage, >truth and tripe as they always have had. The imminent death >of the sci. and comp. groups seems a bit presumptuous. > >I think it takes far more courage to post anonymously than to >hide behind your affiliations. For me, a poster who, >although anonymously, slowly built a strong argument through >a series of well-written anonymous posts and politely >responded to counterexamples and the other stuff of a good >debate, would capture my respect far more than Dick >Reputable, Ph.D.@bigfoo.com making a simple pronouncement on >the whole matter that his net-flacks are expected to parrot. I read and accept Henry Spencer's posts, and the only credentials he posts are that he is somehow associated with the University of Toronto Zoology department and, from other posts, something of a UNIX and NNTP wizard. > >Yes, it takes more effort to get your mind around anonymous >posts than attributed ones: we get out of the habit of >evaluating arguments without the guiding badges and trappings >of authority accompanying them. Those posters who have >forgotten how to legitimately persuade and, through time and >accreting rank, have relied upon the prestige of their >posting site may well have reason to fear the new order of >things. But the content of the argument ought to be >important for all posters, not just the ones who do not have >a Keogh plan or a doctorate. Certainly most scientists agree >that the necessity of experimentation, systematic >observation, and falsifiability supporting a scientific truth >applies equally to the member of the Academy as well as the >first-year lab assistant. > >The concept of anonymous posting is the next great step in >washing away the detritus that impedes our search for truths. >Yes, it has a great capacity to annoy and anger, but it has >an even greater capacity to engage the truth for those with >courage enough to learn to use it universally and well. You way you can improve your credibility is to go back to your doctor and ask for some Stellazine and Trilifon and Benedryl for the sides. -- Dillon Pyron | The opinions expressed are those of the TI/DSEG Lewisville VAX Support | sender unless otherwise stated. (214)462-3556 (when I'm here) | (214)492-4656 (when I'm home) |When in fear, or in doubt pyron@skndiv.dseg.ti.com |Run around, scream and shout. PADI DM-54909 | And I apologize to the rest of your for burning your disk space and personal time. ------------------------------ Date: Sun, 7 Mar 1993 07:46:04 GMT From: Nick Szabo Subject: Water resupply for SSF (?) Newsgroups: sci.space gary@ke4zv.uucp (Gary Coffman) writes: >Deployment and aiming are the >stickiest problems associated with sails, or flexible mirrors. >Remember that we're talking about an organization that can't get >an antenna to deploy, or a winch to reel out cable. Gee, I get to upbraid Gary for NASA-bashing! NASA has successfully deployed several large antennas on its TDRSS series without a hitch. The U.S. military has deployed dozens of these, including 100-ft. monsters. The Russians recently tested their solar mirror (any news on that?). Henry Spencer's small group apparently thought such deployments are feasible on the cheap. I didn't say deployment was simple; I just pointed out it doesn't require advanced AI, anthropocentric robots, and other strawmen that the Luddites keep raising against automated missions. The volatile extraction business scenario assumes odds of deployment failure similar to those on commercial or military systems, and involves dozens of small ice rockets, not one big one. I never said NASA should do this project; rather they should study it, R&D to the prototype stage, buy the product, and above all include it in their vision of the future. We space activists also need to include it in our vision of the future. The mission itself should be commercial, with multiple international customers not detailed-spec contracts from a single government agency. Complexity is a function of quality, not quantity. If a large-scale volatile extraction mission is more complex than Rosetta it would be due to differences in complexity between keeping a material pure and purifying a material, not due to differences in the volume of material. Those are two different tasks, but I'm not convinced that one is substantially more complex than the other; even less am I convinced that this requires as-yet-undiscovered AI or anthropomorphic robots. Both missions require very good quality control, software engineering, and mission planning, and for Rosetta sample return most space scientists and engineers figured this was quite doable by the mid-1980s. The state of the art has advanced quite a bit since then with VR, teleprogramming, and the deployment of many different kinds of ocean-going remote, automated oil drilling and well maintenence equipment. This equipment works in a similar environment (mud & organics & water) with high mass-thruput ratios (even though mass is not much of a consideration in the ocean, so this variable could likely be improved substantially for space missions with high-strenth polymers, miniaturization, etc.) Likewise, there is no necessity to follow your pilot-plant development plan so strictly. Oil companies every year drill through miles of rock, gravel, mud, permafrost, ice, etc. that they haven't mapped out in detail beforehand. Similarly mineshafts and tunnels are drilled, etc. with general-purpose equipment through highly variable and not necessarily predictable geology. The comet mining equipment will be extensively tested on Earth, and in microgravity in low earth orbit, and designed to handle a wide variety of comet surface conditions. Techniques for mapping and adapting to a wide variety of comet surfaces should be developed for the comet sampling probes, a task appropriate to NASA. The first missions to the comet will be high risk and high payoff -- reducing the cost of materials in earth geosynchronous orbit by two orders of magnitude, for example. The first missions will be operational. Even though oil workers are orders of magnitude less expensive than astronauts, oil companies are starting to find such automation worthwhile. We're also starting to see automation applied in Antartic science (robot airplanes, Dante, etc.) even though the scientists there are also orders of magnitude less expensive than scientists in space. As the oil companies, Antartic scientists, etc. demonstrate the equipment and work out the bugs (I will be the first to admit there are bugs!), the objections to automation will evaporate in the face of demonstrated technology wrt any serious commercial proposal to process materials native to space. (I'm sure those seeking NASA Moon-base & Mars-mission contracts will continue touting astronauts and bashing automation for some time to come, even as they do "space resource" studies here and there for PR effect, but vying for NASA contracts is not what I mean by commercial). -- Nick Szabo szabo@techboook.com ------------------------------ Date: Mon, 8 Mar 1993 15:06:01 GMT From: Gary Coffman Subject: Water resupply for SSF (?) Newsgroups: sci.space In article szabo@techbook.com (Nick Szabo) writes: >henry@zoo.toronto.edu (Henry Spencer) writes: >>The deployment phase is the single diciest part of a sail design... > >Nevertheless, you think a small group of volunteers can pull it off, >no? I'm arguing the Russians can pull it off, a small group of highly >paid commercial professionals can pull it off, etc. Mirror >deployment isn't anywhere close to being a show-stopper that would >cause us to throw up our hands and say, "we need astronauts!", as Gary >implied. No, no, no, I outright *said* we can't *afford* astronauts for these missions. I didn't imply they were necessary at all. I did say the job would be much easier *if* we could afford, technically as well as fianancially, to send humans, but we can't. >>[Rosetta']s been considered worth a try, as a high-risk >>high-payoff mission, since the mid-1980s. As I recall, problems like >>preservation of the samples during return were considered minor ones >>compared to the difficulties and uncertainties of the comet-surface >>operations. > >The uncertainties are similar for both Rosetta and comet mining, >regardless of material volume. These uncertainties weren't anywhere >close to being a show-stopper. The probe sends back detailed pix >for over a month, so that the best site can be picked, and can relocate >of the first landing site doesn't work. Rosetta-type missions develop >this kind of technique reducing the risk of commercial mining I also agree that precursor flights, many, are needed to develop technique as well as doing survey work. I do contend that scale is a major factor, however. Historically, table top models have not scaled to pilot plant or production plant sizes without major problems and major design changes. When the mass flow is measured in tonnes rather than grams, processes usually have to change. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ End of Space Digest Volume 16 : Issue 291 ------------------------------