Date: Fri, 5 Mar 93 05:00:05 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #273 To: Space Digest Readers Precedence: bulk Space Digest Fri, 5 Mar 93 Volume 16 : Issue 273 Today's Topics: Alternative space station design (2 msgs) Aurora (rumors) (2 msgs) Battery Help Needed Fire in the Sky Gravity-NEUTRALIZING Spac Low Earth Orbit in a Mars Blimp? (2 msgs) military aircraft nasa Opening up Space to everyone! orbital elements of VOYAGER I-II Reliable Source says Freedom Dead, Freedom II to be developed SSF Resupply (Was Re: Nobody cares about Fred?) (3 msgs) Water resupply for SSF (?) 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: Wed, 3 Mar 1993 21:43:36 GMT From: Rob Healey Subject: Alternative space station design Newsgroups: sci.space In article <1993Mar2.203400.13715@aio.jsc.nasa.gov>, Dr. Norman J. LaFave writes: |> * Alternative modular structures (NO TRUSS): |> |> * Each module, when it is brought up on the shuttle, is equipped with |> its own temporary, modular control and |> maneuvering system (flight control, guidance, and nav computers, |> jets) which allow it to "fly itself" out of the shuttle bay and "dock" |> with the station. The astronauts then make the "dock" semi-permanent. |> |> * Primary power source---NOT solar arrays! |> |> * Passive flight control---a return to the "Power Tower". |> |> This isn't the most lucid description of this I have ever given, but |> "wadda ya think?" |> Sounds good, probably too good for the dorks in Washington to accept it... B^(. The modularity and passive flight control caught my eye. By the way, how about going further and having man rated modules and non-rated "air bag" type modules, to borrow from another posting. The non-manrated cheepo "spacebags" could be used for storage and maybe plant/food growth and thus save space on the more expensive man rated modules for other things. You free up space in the expensive modules but still have lots of space for stuff and maybe grow some food/oxygen cycle experiments. -Rob ------------------------------ Date: 4 Mar 93 04:46:04 GMT From: Gary Coffman Subject: Alternative space station design Newsgroups: sci.space In article <1993Mar3.194542.5295@aio.jsc.nasa.gov> Dr. Norman J. LaFave writes: > >The U.S.has had 6 RTG re-entries with not one leak. The USSR >had one rupture in Canada, but it was found to have insufficient >shielding. The safety issue is one of perception. The Canadian re-entry was a *reactor* not an RTG. Much nastier. >This was an attempt at a lower cost solar dynamic system. Imagine a plate >built as a three-layered sandwich---two heat conductors with a good >thermal insulator between them. Point one conductor at the sun (the other >one is then in shadow) and run a thermocouple between the conducting >plates. Of course this is less efficient than the old solar dynamic system >concept, but it is much simpler and the efficiency would probably still >be much better than the photovoltaic cells. Thermoelectric modules don't approach solar cells for efficiency, especially at the low delta T achievable with flat plates. Neither approach solar dynamic in output per volume. Note on the hexagonal modules with removeable walls. It seems this would result in a *lot* more joints that would be required to hold pressure. That would seem to push costs and reliability factors through the roof. Welded cans are lots cheaper to produce, whether they're hung on a truss or coupled together at docking locks. 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 | | ------------------------------ Date: Thu, 04 Mar 93 15:56:02 MET From: PHARABOD@FRCPN11.IN2P3.FR Subject: Aurora (rumors) >If Aurora exists (I think it's likely), it is not likely to be operating >low enough for anyone to be able to hear it...before, during, or after >the flight. (Steve Hix, 2 Mar 1993 20:55:36 GMT) Probably, but that was not the question ! Somebody said: if everybody hears Aurora, this is not a problem, because it goes so fast... Then I demonstrated (at least, I hope so) that it was a problem. And now, Dean Adams and yourself say: but nobody can hear Aurora ! IMHO, this is not a good way of arguing. >Find some good description of SR-71 operations and note the altitudes >that it flew at during high-speed operation. Most of the time, there >will be no audible signal reaching the ground. When the SR-71 comes >down to drink (being thirsty), it usually spends most of that time >around or below Mach 1...mostly below. Therefore, IMHO, the booms over the Los Angeles area are still unexplained. Why would Aurora need to be there at rather low altitude and hyper- or super-sonic speed ? J. Pharabod ------------------------------ Date: Thu, 04 Mar 93 17:49:56 MET From: PHARABOD@FRCPN11.IN2P3.FR Subject: Aurora (rumors) >>I was answering these guys who wrongly said that the noise was >>not a problem. (J. Pharabod) >Well, they were not wrong to say that. There is no reason to >believe that noise is a problem when one of these aircraft is >at an operational altitude. >D. Adams (3 Mar 93 13:32:15 GMT) But that was not what they said ! They said that the plane was going so fast that it would be far away when the noise would reach the ground. They did not say that it would be so high that nobody would hear it. >>The distance between Los Angeles and Tonopah, where Aurora is said to >>land, is about 280 miles. If Aurora were 100,000 ft up over Los Angeles >NOPE. It would not be that high. More like half that, or maybe less. Do you mean that, if Aurora were 100,000 ft up over Los Angeles, it would be unable to reach safely Tonopah (or Groom Lake) and land there? J. Pharabod ------------------------------ Date: Thu, 04 Mar 93 15:01:37 EST From: Tom <18084TM@msu.edu> Subject: Battery Help Needed >>>I think I'd look into the sexier battery technologies, like nickel-hydrogen >>>or silver-zinc, first. >>And just how does one decide which batteries are "sexy" :-) >You check out the curves, man, check out the curves. I like the ones in the see-thru cases, myself. -Tommy Mac ------------------------------------------------------------------------- Tom McWilliams | 517-355-2178 (work) \\ Inhale to the Chief! 18084tm@ibm.cl.msu.edu | 336-9591 (hm)\\ Zonker Harris in 1996! ------------------------------------------------------------------------- ------------------------------ Date: 3 Mar 93 06:09:08 GMT From: Michael Corbin Subject: Fire in the Sky Newsgroups: sci.space On March 12th, your perception of reality will be substantially changed. You will be transported back to November 5, 1975, when a group of loggers are preparing to go home after a day of work in a Northeastern Arizona forest. What should have been any ordinary day becomes an historical event that would lead to charges of murder, accusations of a hoax, and the ultimate in devastation of personal lives over a story so incredible no one would believe any part of it. On March 12th, Paramount Pictures and Joe Wizan/Todd Black Productions will present "Fire in the Sky," a true story based on the Travis Walton experience, whose abduction by a UFO is one of the best-documented cases in history. The scene is set. As the men travel through the forest over rough roads, miles from civilization, they come upon a strange and unusually bright light hovering in the sky. Travis Walton, being a fearless and perilously curious person, jumps from the truck to approach the object as his friends warn him to return to safety. Suddenly, there is a bright flash of light and Travis is knocked to the ground by a mysterious force of energy. In a panic, his friends leave the scene only to return moments later to find Walton gone without a trace. For five days, his friends are accused of murder while an intense manhunt ensues attempting to find a trace of Walton. On the fifth day, Walton is returned dazed and disoriented only to find that things in the small town of Snowflake, Arizona have changed forever, and he is the cause of it. Telling an incredible story of alien interaction, Walton faces contempt and ridicule that almost destroys his life. Seventeen years later, controversy still surrounds the event, but each of the men involved in that fateful day still stand firm on their stories. "Fire in the Sky" is not a UFO movie. "This is a story that speaks to human character and behavior --- about our inclination to presume the worst in someone before considering ideas that challenge our own skepticism," comments producer Joe Wizan. Screenwriter Tracy Torme' identifies the film as a study of "how a single event can alter your life forever just by (your) being unlucky enough to be in the wrong place at the wrong time. 'Fire in the Sky' is also about friendship and betrayal --- and forgiveness." "Fire in the Sky" stars D.B. Sweeney ("The Cutting Edge"), Robert Patrick ("Terminator II: Judgment Day"), Craig Sheffer ("A River Runs Through It"), Peter Berg ("Late for Dinner"), and Academy Award nominee James Garner. Directed by Robert Lieberman. Wolfgang Glattes is the executive producer and Tracy Torme' & Robert Strauss and Nilo Rodis-Jamero are the co-producers of the presentation. A must see for everyone! ParaNet will carry a review of the presentation. -- Michael Corbin - via ParaNet node 1:104/422 UUCP: !scicom!paranet!User_Name INTERNET: Michael.Corbin@p0.f428.n104.z1.FIDONET.ORG ------------------------------ Date: 3 Mar 93 08:20:00 GMT From: Roland Dobbins Subject: Gravity-NEUTRALIZING Spac Newsgroups: sci.space M > M >From: mcelwre@cnsvax.uwec.edu M >Newsgroups: sci.space M >Subject: Gravity-NEUTRALIZING Spacecraft M >Message-ID: <1993Mar1.172425.4516@cnsvax.uwec.edu> M >Date: 1 Mar 93 17:24:25 -0600 M > M > The ZERO/REDUCED-Gravity Chamber described below has obvious p M >applications for Chemistry, Biology, Biophysics, Biochemistry, Medi M >Research, etc., allowing experiments which now can be done ONLY on M >Shuttle, AT GREAT EXPENSE! M > M > M > Gravity-NEUTRALIZING Air/Spacecraft M > or ZERO/REDUCED-Gravity Chamber M > M > NASA should build an experimental spacecraft based o M > U.S. Patent #3,626,605 [at least $3.00 per complete copy M > U.S. Patent Office, 2021 Jefferson Davis Hwy., Arlington, M > 22202; correct 7-digit patent number required. Or try ge M > it via your local public or university library's inter-li M > loan dept..], titled "METHOD AND APPARATUS FOR GENERATING M > SECONDARY GRAVITATIONAL FORCE FIELD", awarded to Inventor M > Henry W. Wallace on Dec. 14, 1971. M > M > In the patent, Figs. 7A and 7B are basically side vi M > of a gravity-NEUTRALIZING FLYING SAUCER, or, if anchored M > the ground, a ZERO-GRAVITY CHAMBER [which could have MANY M > possible GROUND-level applications for science, medicine, M > manufacturing, etc.]. Each oval diagram shows a motor M > spinning a central disc at a very high speed, about 28,00 M > RPM, and also rotating two other discs sandwiched around M > first disc, via gears, at a much slower speed, perhaps 2, M > RPM, in the opposite direction. The two outer discs have M > extensions [counter-balanced via off-center axis] that, a M > they rotate, alternately make contact with two wide M > extensions from opposite walls of the spacecraft. The M > central disc should have shallow spiral-shaped grooves on M > both sides for air-bearings, to allow the needed very clo M > contact with the two outer discs. M > M > I should clarify that each of the two outer discs ha M > ONLY ONE [counter-balanced] extension, each one pointed M > opposite (180 degrees) the extension of the other disc. M > M > VERY CLOSE CONTACT must be made as the disc extensio M > slide past the wall extensions in order to conduct the M > "Kinemassic" Energy (term coined by the Inventor) from th M > discs to the walls in an ALTERNATING CIRCULATION. M > M > The most important factor making it work is that the M > discs, extensions, and outer walls of the spacecraft MUST M > made of any material(s) in which a very large majority of M > atoms are of isotopes having "half integral atomic spin", M > such as copper (3/2). All other parts, etc., should have M > minority of such atoms. [See the appropriate column of t M > table of isotopes in the latest edition of "The Handbook M > Chemistry and Physics."] M > M > Experimenters should use one motor to spin the cente M > disc, and a 2ND SEPARATE motor to rotate the two outer di M > so their relative speeds can be varied to establish the M > needed conditions for PROPULSION of the spacecraft via M > "NEGATIVE WEIGHT" (with the spacecraft's "Kinemassic" fie M > PUSHING AGAINST the earth's gravitational field, etc.). M > M > M > If we have to put up a space station, establish Moon M > bases, go to Mars, rendezvous with comets, etc., WHY DO I M > THE HARD WAY?! M > M > Your favorite university or research company could m M > a big name for itself by making a small model of this wor M > M > M > UN-altered REPRODUCTION and DISSEMINATION of this M > IMPORTANT Information is ENCOURAGED. M > M > M > Robert E. McElwaine M > B.S., Physics and Astronomy M > M > That's nuts . . . --- . Orator V1.13 . [Windows Qwk Reader Unregistered Evaluation Copy] ------------------------------ Date: 4 Mar 93 03:59:19 GMT From: Gary Coffman Subject: Low Earth Orbit in a Mars Blimp? Newsgroups: sci.space In article <1993Mar2.151520.1@acad3.alaska.edu> nsmca@acad3.alaska.edu writes: >I know this is a wierd idea, but seeing other articles on blimps, what is the >possibility of using a blimp or soem form of it, to get out of earth orbit or >atleast to put yourself into low earth orbit.. I know there is a limit to the >atmosphere, but how far up is it?? If you can build a blimp on Mars and its >atmosphere and such, why not build on on earth to.. Airships work by displacement. They can rise no higher than the point where they weigh as much as the air they displace. Since the air gets very thin very quickly with altitude, no practical balloon can reach what we call outer space. LEO is basically in the 200 km range for something that intends to stay up for a reasonable time. Balloons can reach at best 50 km altitude. Even if you could get a balloon to 200 km, it wouldn't be in orbit. Achieving orbit requires a certain velocity vector tangental to the gravity vector. That's roughly 8 km/sec for LEO. Supersonic blimps don't exist. That's not to say that balloons can't be useful in getting you to orbit. There used to be a program that launched rockoons. That's a rocket carried aloft by a balloon. When the balloon reaches it's maximum altitude, the rocket fires through the balloon envelope and proceeds to higher altitude. This hasn't been used for an orbital shot, just sounding rockets, but it's conceivable that such a system could eliminate the large first stage booster of an orbital rocket. Large expendable balloons aren't cheap, however, so there's little practical advantage to be gained by going to rockoons instead of conventional boosters. 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 | | ------------------------------ Date: Thu, 4 Mar 1993 04:33:48 GMT From: Gary Coffman Subject: Low Earth Orbit in a Mars Blimp? Newsgroups: sci.space In article henry@zoo.toronto.edu (Henry Spencer) writes: >In article <1993Mar2.151520.1@acad3.alaska.edu> nsmca@acad3.alaska.edu writes: >>I know this is a wierd idea, but seeing other articles on blimps, what is the >>possibility of using a blimp or soem form of it, to get out of earth orbit or >>atleast to put yourself into low earth orbit... > >The central problem of attaining orbit is velocity, not altitude. Balloons >can't operate to anywhere near orbital altitude, although they can be a >useful first step: there have been balloon-launched sounding rockets. >But the velocity gap is even larger. You don't see many Mach 1 blimps, >much less Mach 25 blimps. I said roughly the same thing Henry, but now I'm wondering. Is a supersonic blimp possible? Might be an interesting civil transport design, a VTOL SST. 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 | | ------------------------------ Date: 3 Mar 93 08:20:00 GMT From: Roland Dobbins Subject: military aircraft Newsgroups: sci.space MC> MC>Newsgroups: sci.space MC>From: merle@a.cs.okstate.edu (MERLE CHRISTOPHER) MC>Subject: Re: military aircraft MC>Message-ID: <1993Mar1.221452.4021@a.cs.okstate.edu> MC>Date: Mon, 1 Mar 93 22:14:52 GMT MC> MC>In article <76487@cup.portal.com> BrianT@cup.portal.com (Brian Stua MC>>>The A-12 was intended to replace the aging A-6. It ran into MC>>>management problems, overran budget, and has been cancelled. Aur MC>>>is the (rumoured only) replacement for the SR-71 Recce aircraft, MC>>>has (once again, rumoured only) reportedly been flying for a numb MC>>>years now. MC>> MC>> The writer probably confused "Aurora" and "Avenger". However, MC>> not sure that the A-12 Avenger II was even supersonic, much le MC>> designed for Mach 4. MC>> MC> MC>Historical Tidbit: The first plane to receive the designation A-12 MC>the precursor to the SR-71. the A-12 was operated by the CIA. MC> MC>As for rumoured replacement. The SR-71, the A-12, the F117A were se MC>many years before they went public. So it is reasonable to assume t MC>the USA has a replacement. After all the original designs for the MC>dated from the late 40's. You decide. MC> MC>Yours in Paranoia MC>Chris MC> MC> MC>-- MC>------------------------------------------------------------------- MC> Christopher Merle | "As God as my witness, I thought tur MC> merle@a.cs.okstate.edu | could fly." --Art Carlson MC>------------------------------------------------------------------- Er . . . the original SR-71 designs aren't from the 1940s, I think. Kelly Johnson built the SR-71 during 1961-1962 at the Lockheed Skunkworks, if I'm not mistaken . . . --- . Orator V1.13 . [Windows Qwk Reader Unregistered Evaluation Copy] ------------------------------ Date: Thu, 04 Mar 93 11:22:20 EST From: HCQ8000 Subject: nasa Where can I find the latest info concerning NASA's shuttle launch? ------------------------------ Date: Thu, 4 Mar 1993 00:31:19 GMT From: "Simon E. Booth" Subject: Opening up Space to everyone! Newsgroups: sci.space In article <1993Mar2.175207.27994@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >In article <1993Mar2.002113.19301@ringer.cs.utsa.edu> sbooth@lonestar.utsa.edu (Simon E. Booth) writes: >>>In article djf@cck.coventry.ac.uk (Marvin Batty) writes: >>>> >>>>With equal opportunities legislation, coupled to a good standard of medical >>>>support (not unlike standard life-support!) the presence of disabled people >>>>in space seems a real possibility. There really isn't any need that I can see >> >>I had been wondering the same thing myself. Due to a back problem I have >>difficulty standing or walking more than 30 seconds at a time. >> >>This makes getting around under normal one-g difficult, to say the least. >> >>Theoretically, would this make adapting to zero-g easier? I know the >>multiple g's of a launch would probably be a problem, so this is probably >>only a thought-exercise at best. Still, for someone has has problems under >>normal gravity, would microgravity eliminate those problems or is there >>something I'm missing in this theory. > >Unfortunately the back is more than just a support structure against >gravity. It acts as lever or anchor for many muscular exertions that >occur regardless of gravity. Since mass, and inertia, don't decline >in micro-g, you still have need for muscular exertion to get work >done. The documented calcium loss in micro-g might even aggravate an >already weakened skeletal conditio I completely forgot about calcium loss! I was thinking about short-term wear and tear, which is definitely aggravated by one-g. Now, if they ever build a space station with artificial gravity, I could simply head over to the zero-g area for brief periods. But then I'd have to find a vehicle that won't exceed 1.5 g on liftoff. One must be patient waiting for technology to advance.... (really patient!) :-) Simon ------------------------------ Date: Thu, 4 Mar 1993 13:19:10 +0100 From: kayal@ws550.sr.kp.dlr.de Subject: orbital elements of VOYAGER I-II I am looking for the orbital elements of the planetary probes VOYAGER I-II to verify some trajectory evaluations. Does somebody know where I can get them from? Hakan Kayal kayal@ws550.sr.kp.dlr.de ------------------------------ Date: 4 Mar 1993 00:29:37 -0500 From: Pat Subject: Reliable Source says Freedom Dead, Freedom II to be developed Newsgroups: sci.space In article <1mv3ie$lol@agate.berkeley.edu> gwh@soda.berkeley.edu (George William Herbert) writes: > > [Serious == among other things "the solar panels will FALL OFF"] > > This is not a minor problem. It's an institutional disaster. Oh this one is minor, compared to the Good One I heard. Before they Killed the 20Khz 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 thing will never fly anyway" pat ------------------------------ Date: Thu, 4 Mar 1993 03:22:41 GMT From: Gary Coffman Subject: SSF Resupply (Was Re: Nobody cares about Fred?) Newsgroups: sci.space In article <1mv3s1$lqi@agate.berkeley.edu> gwh@soda.berkeley.edu (George William Herbert) writes: > >That's not the point. The PURE OPERATIONS cost of shuttle is half >of NASAs budget. That is not research, tech development or science >related, that's the cost that shuttle just by itself incurrs. 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. There's dispute over how to account for some of the standing army, but that includes costs directly associated with Shuttle. If you look only at incremental costs, a Shuttle flight costs around $300 million tops, 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. 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 | | ------------------------------ Date: Thu, 4 Mar 1993 03:15:57 GMT From: Gary Coffman Subject: SSF Resupply (Was Re: Nobody cares about Fred?) Newsgroups: sci.space In article <1mtsjaINNeko@access.digex.com> prb@access.digex.com (Pat) writes: > >NASA has a 13-14 billion dollar budget. THey could fund any program >ona multi-year basis. They just odn't choose to. They want to waste >money. it justifies jobs better. If only this were true. Congress has a standing policy of not approving multi-year budgets. They refuse to obligate future Congresses to specific expenditures. NASA does not have the legal power to do this on their own. They must, by law, either spend their appropriation within the fiscal year or return the money to the Treasury. (Actually they never draw it in the first place, but that's the language of the appropriations bills.) This has had major impacts on all long term NASA programs because year to year funding has been a political football. On occasion, Congress has granted NASA some discretionary money, but funds for major programs are detailed in authorization bills and can't legally be diverted to other projects. If NASA's 14 billion dollar budget were discressionary funding, and if NASA had some assurance that future Congresses would maintain that level of discressionary funding, then they could responsibly plan multi-year budgets for programs. But it doesn't work that way. All major budget line items are dedicated, by Congress, to specific projects. Congress decides, each year, what projects to fund that year, and by how much to fund them. It's out of NASA's hands. All NASA can do is lobby Congress for support for specific projects and hope their political skills are up to the task of competing with other funding pressures on Congress. 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 | | ------------------------------ Date: 4 Mar 93 04:23:39 GMT From: Gary Coffman Subject: SSF Resupply (Was Re: Nobody cares about Fred?) Newsgroups: sci.space In article <1993Mar3.141038.18298@iti.org> aws@iti.org (Allen W. Sherzer) writes: >In article steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes: [AWS] > >>This is also why I think the high-end numbers >>for STS cost per pound to LEO are nonsense, they amortise all >>of NASA's (space) operations to orbit delivery > >Not so. The cost given is the total anual Shuttle costs divided by ten >or so flights a year. This gives Shuttle every possible break. Despite claims, including by NASA, to the contrary, 50 some odd flights does not make an operational system. Every Shuttle flight is to some extent a test flight. New problems, and old but unfixed problems, crop up on every flight. This experience base being gathered is properly a developmental cost. Shuttle has already taught us many things we should, and shouldn't, do to achieve a cost effective spaceflight system. Every flight adds to that database. At some point we must say "enough" and go on to another system, but going *backwards* to forty year old ICBM technology is not an answer. The next system, the Shuttle successor, should incorporate the lessons learned with present and past systems. That's the only way astronautical development can progress. SSTO or NASP may develop into that successor, or not, depending on their development progress, but we won't know without flying hardware. Shooting off old stale ICBMs doesn't bring any progress to the table. >>when a lot of the >>R&D is going to take place independent of missions actually flown, > >Agreed. It therefore seems wise to insure that NASA pays as little as >possible for those services. Not only does this allow more research to >be done but it also promotes space activity by lowering the cost. You can't gather development information unless you fly the system. If you can carry payloads in the process, that's just gravy. NASA would be fulfilling it's R&D charter if it hauled lead weights to and from orbit. Being able to actually piggyback some working payloads onto developmental launchers is just a spinoff benefit. >Irrelevant. The value of past research can't justify wasting money >today. That argument is called "eating the seed corn." Just because payoffs are down the road doesn't mean we don't have to spend the money today. 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 | | ------------------------------ Date: 4 Mar 93 03:47:29 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: > >>>[automated comet mining] >>Someday. Not today. This is *far* beyond what can be done with current >>robotic systems. > >The two most complicated pieces of automation needed are >(a) ice extraction and (b) solar mirror deployment (for the solar >thermal version). Surely you have some confidence in (b), or you >wouldn't have been designing solar sails for the contest. As for >(a), a similarly complex operation, the extraction and return of >several comet core samples, keeping them pristine-pure the entire way >back to earth and through reentry, has been considered feasible >in the space science community since the mid-1980s. Neither that >mission (Rosetta) nor comet mining require anthropomorphic robots or >undiscovered "AI". (b) is not as simple as it sounds. 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. (a) is the real show stopper however. Rosetta is intended to capture and return a *tiny* core sample, not industrial quantities of materials. Magnitude does make a difference. Even here the largest unknowns are how to get the sample from an a priori unknown surface. Refrigeration and transport are the easy parts. To handle industrial quantities of materials, benchtop processes don't cut it. Developing industrial mining and refining processes requires fieldwork that simple robot probes aren't capable of handling on site. The steps to get industrial native materials mining and refining going without manned input would go something like this. First a survey mission must be launched to quantify the surfaces and materials available at the target site. After this info is digested, a pilot process is developed on Earth and shipped to the site. The inevitable problems and failures are then analyzed. A new pilot plant is constructed and shipped on site iteratively until something works right. Then a production plant is built and shipped to the site. Hopefully the scaling worked and you're in business. Otherwise, another plant is built and shipped on site. Etc. Repeat this process for every site that isn't precisely the same. Eventually you get good at it and can ship adaptable and adjustable processing equipment to any similar site with high confidence that it will work with minimal problems. Having manned presence at the site, along with machine shop services and access to various bits of equipment, can telescope this process dramatically, but costs for manned mining and refining missions are just out the window due to the large life support and transport costs involved. 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 273 ------------------------------