Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Wed, 14 Nov 1990 01:42:42 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Wed, 14 Nov 1990 01:42:10 -0500 (EST) Subject: SPACE Digest V12 #545 SPACE Digest Volume 12 : Issue 545 Today's Topics: Re: LLNL Astronaut Delivery The great light bulb debate Ulysses Update - 11/09/90 Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription notices, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 9 Nov 90 04:52:35 GMT From: sumax!thebes!polari!crad@beaver.cs.washington.edu (Charles Radley) Organization: Seattle Online Public Unix (206) 328-4944 Subject: Re: LLNL Astronaut Delivery References: <2669@polari.UUCP>, <9011072124.AA13810@iti.org> Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu +this will be my last reply (nothing new is being said anyway). Mr. +Radley is welcome to have the last word. - I found your posts most stimulating and enlightening, I hope you will continue to share your news and thoughts as time permits. Let me add some "new" thoughts...... +My preference is to let them fight it out. Fund both until one is + up and working then kill the other. A little competition goes a long way. - It looks more like Freedom and LLNL could be COMPLIMENTARY, since they appear to have different missions. The question is, which mission(s) is/are the right ones. I am opposed to Mars missions, but favor a lunar base processing lunar soil. Since Great Exploration is Mars oriented, I don't like it. +BTW, how many space stations has your employer built? If the answer is not at least 3 then I would say you don't have a track record either. - My employer is not building a space station, and probably never will. We have been making space mechanical subsystems for over 20 years. Our customer, McDonnell Douglas, built Skylab, which was the US's only space station. The Freedom contractors have an average of 20 years experience in large space systems. +No I quote the original cost and schedule as provided to Congress + in 1984. - Congress was provided with various estimates as the program developed. 1984 was the Rockwell era. Later, Phase-C was awarded to a different consortium who quoted a different price. +Freedom FEL comes up there will be TWENTY flights ahead of you. Is +Freedom going to tell those people to take a hike? - It is similar to a planetary mission with fixed launch windows, Ulysses and Galileo got up on schedule, and other flights worked around them. +Actually, it makes micorgravity better. By putting the microgravity +facility in a crew-tended free flyer it won't be subjected to the +vibration which Freedom will subject it to. - True, but it won't benefit from continuous manned presence to fix problems. For a free-flyer to fly "in-formation" with a nearby manned base will require frequent disruptive thruster pulses, so it is not totally quiet. Otherwise it would have to rely on nodal regression to rendezvous with a station, with weeks or months of no human access. >It also makes studies of biological effects of zero-g impossible. +You could add a zero-G module in the middle if you want. Or if the +LLNL station demonstrates the viability of the concept you can build +large 0G stations for a very very small amount of money. - You get cheap empty shells, it costs plenty to fit them out with state of the art scientific equipment. LLNL may be lighter and cheaper than using metal modules a' la Freedom, but most of Freedom's weight and cost is in the science and support equipment, the module structure is small fraction of the total. + [text deleted] Now if this redesign happens, I would tend to +support it (provided commercial needs are met). - What commercial needs ? It puzzles me why people such as yourself prefer a small station to a big one. Every year Freedom's capability is cut, and the schedule slipped. We, the designers, find it most frustrating. I think it would have been cheaper in the long run to have built the station which was bid 4 years ago. Since then congress has blown about 10,000 man-years of effort by forcing annual redesigns. And then people such as yourself blame it on NASA and the contractors, AARGH ! +So tell me, what is the value of man rating when man rated systems +end up being no safer but four times as expensive as the non-man +rated ones? - That was not true of Mercury through Skylab, nor Vostok through Soyuz. >You mean they will design, build and fly twelve precursor (Gemini) >spacecraft to develop the technology, +Yep. Those missions have already been flown (the program was called +Gemini). That knowledge didn't just e+rase itself you know. - Gemini did not test inflatable space structures. Nobody has done that. Much of the Gemini heritage has been erased, try and get a set of Gemini manufacturing drawings. +The station flies up unmanned and inflates itself. When the +environment is OK, people go on board. What's wrong with this? - Nothing that a full qual program can't fix :-) >+Yep it has. Tell me, in 90 $$ how much does an Apollo capsule >+cost? >The tooling for Apollo has been destroyed, and there are >very few drawings left. Apollo's cannot be built for all the tea >in China. You will have to build a new vehicle. +You didn't answer my question. How much in 90 $$ does an Apollo CM +cost? Please provide a source. After all, how can we estimate the +true cost of developing a suitable capsule without looking at past +experience? - I did answer, all-the-tea-in-china is a euphamism for "indeterminite very high cost". Nobody can give a numerical answer today. And why do you want an obsolete museum peice ? New electronics and new materials permit more lightweight designs. Heck, those old Apollo computers simply ain't available any more. It is like asking today's Detroit to build you a model-T Ford, even if they could figure out how, it would take forever and nobody could afford to buy one ! The Japanese and ESA concluded that a new winged mini-shuttle is the answer and they talk $ 10s of Bs, NASA is not alone. A CM is not adequate because it could last about 30 minutes on battery power, you would need an SM to go with it. +Nope. A Titan III costs $125M list (Avation Week Jan 8, 1990 page +43). A Titan IV is less than 200M (150M according to Tech. Review). - I stand corrected. +Two Titans gives you more interior room than Freedom. - Interior volume is not particularly exciting, except for recreation. Maybe useful if we ever get a space tourism industry up and running. Right now more interested in maximum science for minimum weight and cost. >Pads 40 and 41 are already in use by USAF and commercial users. >The launch rates you quote require at least one new additional pad. +Yes the pads are in use. That doesn't mean they are unavailbe all +the time. According to OTA, no new pads are needed to achieve this +launch rate. - I have personal experience of a case where a Commercial Titan launch was bumped by a military launch. The pads are already very busy. If Henry Spencer is correct, and State Dept awarded an export license to USBI, then LLNL should be talking to them because Zenit is much cheaper than HLV or Titan. +Finally, I note that Mr. Radley has not made any major points +against the LLNL approach. His only complaint, testing, is invalid +because LLNL does do testing using methodologies considered +adaaquate for Apollo. Mr. Radley has given no detailed assessment +of why LLNL testing methodology is flawed for the level of risk +assumed and his - Testing is neither my only nor my biggest complaint. The "biggie" is the total lack of any realistic proposal for a manned ferry craft, $ 200 M doesn't cut the mustard, and US Law prohibits collaboration with the Soviets, so forget Soyuz etc. I am not familiar with LLNL's specific test approach, and you have not posted anything specific for me to critique. The costs quoted rule out Apollo style testing. To assume the first flight article will inflate first time is optimistic. And I said all along, my main problem is the cost, not so much the technical approach. +other comments indicate that he doesn't understand how the program works. - Probably true, have had trouble getting data. Unwilling to contact LLNL myself, very little available public domain. ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: Fri, 9 Nov 90 17:13:28 EST From: John Roberts Organization: National Institute of Standards and Technology formerly National Bureau of Standards Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. To: space@andrew.cmu.edu Subject: The great light bulb debate Apologies if this is out of date. SPACE Digest has been down for about a week. >Date: 29 Oct 90 16:07:30 GMT >From: usc!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca!neufeld@ucsd.edu (Christopher Neufeld) >>> On one of the shuttle missions, send up thousands of tiny glass >>>spheres with small holes in them. Once in space, expose the spheres to >>>the vacuum of space and then seal them. Bring them back to earth >>>and sell them to people. Everyone can own their own piece of space! >> > A glass ball with a vacuum inside is a bad thing to have around. If >it is broken it implodes, and the pieces fly through the centre of the >sphere, and on across the room at high speed. People doing vacuum >experiments prefer metal containers whenever possible to prevent the >formation of shrapnel. You'd need a plexiglass shield around the vacuum >sphere to make it safe. > I'd hesitate to hold even a 1mm diameter vacuum sphere in my hand. If >it shattered it would send glass into my palm, and you don't want to >consider what would happen if you held it close to your face so that you >could see the tiny sphere more clearly........ > Christopher Neufeld....Just a graduate student | "The pizza was just a .............................. >Date: 30 Oct 90 17:26:15 GMT >From: news-server.csri.toronto.edu!utgpu!utzoo!henry@rutgers.edu (Henry Spencer) >Modern light bulbs are filled with argon, not vacuum. (Expensive ones >use krypton.) As you imply, the old bulbs were evacuated. I believe the main reason for the switchover to inert gas was to reduce the rate of evaporation of the filament at a given temperature. The "inert" gas usually cited in the literature is nitrogen. Why would krypton be better than argon? Halogen lamps use a halogen gas, which absorbs the tungsten evaporated from the filament (and redeposits it?), allowing the filament to be operated at higher temperature and efficiency. >CRTs are quite dangerous to handle "naked", and people >who work with them are careful; when enclosed in a monitor, one of the >safety requirements is that the faceplate be tough enough that an >implosion would not send fragments toward the user. Safety-certification >agencies like UL and CSA test this regularly. >Chris N. is not kidding about the serious safety implications of glass >vacuum containers. However, a quick fix would be to encase them in >plastic. For instance, I believe flash bulbs pretty much always explode when fired, but the plastic coating holds the glass together. >"I don't *want* to be normal!" | Henry Spencer at U of Toronto Zoology >"Not to worry." | henry@zoo.toronto.edu utzoo!henry .............................. >Date: 30 Oct 90 14:24:53 GMT >From: thorin!grover!beckerd@mcnc.org (David Becker) >Subject: Re: A great idea on how to fund NASA! >Your average incandescent bulb holds slighlty pressurized inert gas. Glass >that thin could never keep O2 out of vacuum. The pressure is to keep >the O2 out and the filament burning. >David Becker I Dweam of Dweanie >beckerd@cs.unc.edu Then how do you account for the working of the old-fashioned bulbs? Remember the scenes from the old films, such as the encounter between W.C. Fields and the blind man, in which light bulbs break with a loud BANG? (One of my favorite scenes from "Our Gang" is the one in which the city kid gets across a busy street by breaking a light bulb. The drivers all stop to check for blown inner tubes, and the kid just walks across. :-) Fluorescent tubes also contain near-vacuum. If one obtains a burned-out tube and purely by coincidence just happens to shoot it with a pellet gun from 50 yards away, the result is a very interesting "thunk" as the tube fills with air, and fragments of glass will travel several feet. (One should then be very careful cleaning up the glass, though with the absence of beryllium in modern tubes, I suppose a cut wouldn't be quite as fatal as in the old days.) The decorative "plasma spheres" also contain a pretty good vacuum, as do radiometers. Disclaimer: Kids, don't try this at home without a signed letter of permission from your congressman! John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 10 Nov 90 04:44:55 GMT From: elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@decwrl.dec.com (Ron Baalke) Organization: Jet Propulsion Laboratory, Pasadena, CA. Subject: Ulysses Update - 11/09/90 Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu ULYSSES MISSION STATUS November 9, 1990 As of 10AM (PST), Friday, November 9, 1990, the Ulysses spacecraft is 19,671,570 miles (31,658,323 km) from Earth, and 455,840,687 miles (733,604,474 km) from Jupiter. The spacecraft is traveling at a heliocentric velocity of 87,017 mph (140,040 kph), and 22,593 mph (36,360 km) relative to the Earth. On Monday, November 5, some further passive monitoring of the nutation phenomena took place. As this had been scheduled as a monitoring only day, no further activities took place. On Tuesday, November 6, the Solar Wind Ion Composition Experiment (GLG) switch-on took place. In addition to the originally scheduled activities, the GRU Channeltron was switched on. It was then followed by the reconfiguration of the GRU experiment. Following this, some further reconfiguration of the STO experiment took place. On November 7, further GLG and STO experiments reconfiguration and testing was carried out. At the conclusion of the day's scientific operations activities, a dynamics test was conducted to introduce a small thruster impulse which aimed to produce an observable short term reduction in the nutation. This was followed on November 8 by two further tests using a larger thruster impulse. The result was that the nutation was reduced by about 20%. However, the dynamic system re-stabilised itself as expected at the nutation value measured prior to the maneuvers after a few hours. Further dynamic tests will be conducted on November 13. Today, the initial switch-on of the Solar X-Rays and Cosmic Ray Bursts Experiment (HUS) commenced. The on-board tape recorder tests foreseen for November 8-9 have been delayed to allow more dynamic testing time. On November 13, the day will be devoted to carrying out further tests in the evaluation of the nutation phenomena. The X-band downlink will also be switched on. As a result this will delay the switch-on of the Low Energy Ions and Electrons Experiment (LAN) by one day. Following the LAN switch-on, it is expected to be able to switch on the Solar Wind Plasma Experiment (BAM) on the originally foreseen date of Friday, November 16. The DSN (Deep Space Network) support has greatly improved. A communications system reconfiguration took place at the DSN Madrid complex. This has significantly reduced the number of data dropouts experienced over the reporting period. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ End of SPACE Digest V12 #545 *******************