Space Digest Fri, 23 Jul 93 Volume 16 : Issue 909 Today's Topics: Clementine (2 msgs) DC-X Prophets and associated problems (2 msgs) DC-X Update (2 msgs) GPS in space (was Re: DC-1 & BDB) Problems in space. Was: Re: Hubble SOlar Arrays, How'd they fould up. Russian/French crew set to leave Mir space station The U.S. and Mir 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: 22 Jul 1993 20:36:59 GMT From: Jordin Kare Subject: Clementine Newsgroups: sci.space In article <1416728cd@ofa123.fidonet.org> David.Anderman@ofa123.fidonet.org writes: > >HS>In article <1214727f8@ofa123.fidonet.org> >HS>David.Anderman@ofa123.fidonet.org writes: >HS>>Clementine will orbit the moon next year, as part of a BMDO sensor >HS>test, but is not *really* a lunar scientific mission... > >HS>Actually, it's not a bad lunar scientific mission, within its limits. >HS> The major limit is that its sensors are not optimized for lunar >HS>science except in small ways (like choice of filters). In particular, >HS?it's a purely optical mission, with no gamma/neutron instruments. > >I am told that it's optics are inferior to the normal NASA optics in >several ways: > >sensitivity to radiation is high (meaning radiation in the space >environment will tend to degrade the images) This is not correct. Clementine's instruments are designed for a 20 krad radiation dose. The primary differences between the Clementine instruments and their sounding-rocket predecessors are improved thermal management and improved radiation resistance, including use of radiation-resistant glasses in optics. Current CCD's do suffer some noise increase due to radiation, but not enough to affect the Clementine data; we are testing new "MPP" CCD's which are hard to 100 krad. > >and the resolution is comparable to a Lunar Orbiter (as in the Lunar >Orbiter from the 1960's). There is some high resolution Lunar Orbiter data, but it's inaccessible (stored on film and/or obsolete-format mag tape) (efforts are being made to scan film and read old tapes to produce "modern" digitized images), covers only a portion of the Lunar surface, is single-color and non-photometric, and does not match the resolution of the Clementine high-resolution camera. > >I am told that this is due to its unique mission (to test BMDO military >sensors) - the optics are extremely small and light, but not to the normal >NASA specs. The optics are comparable in performance to what NASA would fly/has flown in the same size range; we're actually more limited by data transmission bandwidth than by optics in resolution (i.e., the high res camera will take only a few percent of the frames it's capable of taking, because running it continuously would swamp our memory and transmission rate). The major difference from a NASA instrument is the lack of on-board calibration; Clementine will have to rely on pre-launch calibration supplemented by various natural sources (stars, averaged frames of lunar plains, etc.) > >I would love to be corrected on this - Clementine is a wonderful mission, >but I don't want to get our hopes too high that this will be the Lunar >Orbiter that we have all waited 21 years for. > Well, it _is_ a shame we couldn't include a gamma ray spectrometer.... BTW, unlike a NASA mission, the data from Clementine will _not_ be private to the PI's for some period. In fact, the data will be transmitted unencoded, and could be received by many well-equipped hams. I have so far failed to establish contact with the AMSAT folks to try to get this made an actual part of the mission, but if anyone can get the right AMSAT folks to give me a call, please do so. Jordin Kare ------------------------------ Date: 22 Jul 1993 20:47:04 GMT From: Jordin Kare Subject: Clementine Newsgroups: sci.space In article <21JUL199310592311@vx.cis.umn.edu> soc1070@vx.cis.umn.edu (Tim Harincar) writes: >Some questions about the science objectives of the mission: >How much of the surface is intended to be mapped? Poles included? The entire surface of the moon, including both poles, will be imaged over a 2-month period. (There's a small area near one pole that will be in "perpetual dark" during this time). The elliptical orbit means the resolution at the poles will be somewhat worse (about 2x) than in low latitudes. The laser rangefinder will (we hope) obtain surface altitude measurements over about 120 degrees of latitude. > >Do the 10m resloution spot images include any 'artificial' features >(ie Ranger, Lunar Orbiter, LM Ascent stage, S-IV stage impact sites)? > There will be some effort to target interesting sites, but operational limits may keep it to a handful (you lose mapping when you rotate the satellite to look at a specific site, unless you happen to pass right over it). >I think the impact sites would be interesting because you have an object >of known size, shape, mass, velocity and you can see what kind of dent >it made. > >How about other artifacts - Apollo sites, Lunakhod sites, Surveyors, etc. >Apollo & Lunakhod sould be easy since the astronauts turned up so much >new soil with there boots & rovers, should be good contrast... Mostly, >these images would be cool PR, I don't know how much science value they'd >have. There were suggestions that we do at least a few orbits at very low perilune (<<100 km above the surface) and try to get a picture with enough resolution to show the flag "waving" at one of the Apollo sites. Potentially possible, but probably will not be done. > >BTW, according to _Robot Explorers_ by kenneth Gatland, the Lunar Orbiter's >cameras had resoultions of 487m (wide angle) and 60m (telephoto). According >to what Jordin Kare of LLNL posted, Clementine's cameras are ~100m and >about 10m resolutions - better in both cases. So the quality of data >should be pretty good. > >tim harincar We hope so... Jordin ------------------------------ Date: 22 Jul 1993 18:16:56 GMT From: Doug Mohney Subject: DC-X Prophets and associated problems Newsgroups: sci.space In article <22jf1l$lrk@voyager.gem.valpo.edu>, mjensen@gem.valpo.edu (Michael C. Jensen) writes: >Very true point.. which is precicely why I'm pleased DC is being worked on >OUTSIDE government supervision. No, it is working under streamlined guidelines and as a fast-track program. But the bureaucrats are still there. > This is VERY similar to the new system >NASA is stating to work under, and should prove to be a postitive change >for all of us. Mmm, let's see how F turns out (shortened from Fred, shortened from Freedom). January 1993 - John Scully embraces Bill Clinton. July 1993 - Apple Computer lays off 2500 workers, posts $188 million dollar loss. -- > SYSMGR@CADLAB.ENG.UMD.EDU < -- ------------------------------ Date: Thu, 22 Jul 1993 13:43:05 GMT From: Gary Coffman Subject: DC-X Prophets and associated problems Newsgroups: sci.space In article <1993Jul21.232359.26378@cs.rochester.edu> dietz@cs.rochester.edu (Paul Dietz) writes: > >What is most galling about all this is that cheaper, simpler >alternatives that could have reduced launch costs considerably were >under development in the 1960s. For 1/2 the price of running the >shuttle for 1 year (in inflation-adjusted dollars) we could likely >have had a Big Dumb Booster that would launch shuttle-size payloads >for 1/10 to 1/20 the cost of the shuttle. The development risk would >have been much lower. It would not have been as much of a jobs >program for California, though. Are you sure? You'd be building 8 new vehicles a year instead of 3+1 one time. I'd think you'd have more jobs. 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: 22 Jul 1993 16:27:41 -0500 From: hvanderbilt@BIX.com Subject: DC-X Update Newsgroups: sci.space DC-X News, July 22nd, 1993 Copyright 1993 by Henry Vanderbilt and Space Access Society. DC-X Test Program Status DC-X Background (no change in this background section since 7/14 report) DC-X is a low-speed flight regime testbed for a proposed reusable rocket- powered Single Stage To Orbit (SSTO) transport, McDonnell-Douglas Aerospace's "Delta Clipper". DC-X is intended to prove out rocket-powered vertical takeoff, nose-first lifting-body to tail-first flight transition, and tail- first landing. It is also intended to prove out rapid turnaround of a reusable rocket by a minimal ground support crew. DC-X has already pretty much proved out rapid low-cost development of an advanced aerospace X-vehicle type engineering testbed by a small highly- motivated engineering team on a tight budget. Of course, that's been done before -- just not recently. DC-X stands 40 feet tall, is 13 feet across the base, and is roughly cone- shaped, with a circular cross-section forward blending into a square base. The vehicle has four maneuvering flaps, one set into each side near the base, and sits on four landing legs. DC-X masses 22,300 lbs empty and 41,630 lbs fully fuelled, and is powered by four 13,500 lb thrust Pratt & Whitney RL-10- A5 liquid oxygen/liquid hydrogen rocket motors, each able to gimbal +- 8 degrees. The RL-10-A5 is a special version of the RL-10-A designed for wide throttling range (30% to 100%) and sea-level operation. The single DC-X vehicle was officially rolled out of its construction hangar at MDA's Huntington Beach CA plant at the start of April, then trucked out to White Sands, New Mexico for ground and then flight tests. DC-X Undergoing Final Pre-Flight Checkout At Flight Test Site The DC-X vehicle was taken out of storage and trucked over to the White Sands Missile Range (WSMR) flight test site last Friday, July 16th. Once at the site, DC-X was set upright on the launch pad. (An interesting aside -- this pad was originally the concrete base laid down for lifting a Shuttle orbiter onto its 747 carrier aircraft, back when it was thought that WSMR might be used as a regular alternate landing site. The amount of blown dust they had to clean out of the orbiter the one time they landed there has convinced NASA they really don't want to use White Sands again if they can help it.) Now that flight test site setup is done and DC-X moved, the DC-X crew is running a series of ground tests to make sure everything made it over intact and is hooked back together properly. The ground tests should culminate in a "burp test" sometime next week, a four-second firing of DC-X's engines on the launch pad to check that all the plumbing is OK. The first "bunny hop" flight stability test series should begin shortly thereafter. These hops will consist of takeoff, sideways transition of several hundred feet, and landing, done under varying wind conditions. A lot of people will be keeping their fingers crossed during that initial bunny hop, as it will be the first real-world test of DC-X's stability at low speed and altitude. Between crosswinds, "ground effect" (aerodynamic interactions between the rocket plumes, the ground, and the vehicle body), the known fact that computer sims of turbulent airflow are at best black magic, and a general awareness of how much Murphy loves first flights, the Mylanta consumption at WSMR is likely to be prodigious over the next week or two. Good luck, guys. Note that the "bunny hop" series will be restricted to the thirty or so DC-X test crew members plus WSMR support personnel. No media, no VIP's, no public allowed -- not nobody, not nohow. Any stories you may have heard about the public getting in for these are, alas, wrong. First official DC-X flight will actually be the initial flight of the second test series, reaching higher speeds and altitude. This will be the one with speeches, hoopla, VIP's, and media coverage -- but still no admission of the general public. Chances are good for TV coverage, between NASA Select, local TV stations, and the national networks. Chances are also good that you'll be a whole lot more comfortable watching it on TV at home, as the test site is fifty miles of back road into a military reservation, run under military security, under the summer New Mexico desert sun. You'll likely have a better view on TV too, since the "VIP" viewing site will be five miles from the pad. The end-for-end transition maneuver won't be tried until the third, final flight test series. Tentative dates for the start of the first and second flight test series are still July 29th and August 9th, respectively. The exact dates depend on a lot of factors and likely won't be known until a couple days beforehand. Some delays are likely, however, as the pad area has to be cleared anytime there are lightning strikes within five miles (a fairly standard safety precaution when working on large rockets) and New Mexico is in the midst of monsoon season, with thunderstorms common. DC-X Followon: Political Status Background The current DC-X program is funded through flight test and data analysis this fall, and ends after that. There is an ongoing effort to get the US Congress to fund a three-year followon program, currently called SX-2 (Space Experimental 2). This tentatively looks like being a suborbital vehicle powered by 8 RL-10-A5 engines, capable of reaching Mach 6 (about 1/4 orbital velocity) and 100 miles altitude, built with orbital-weight tanks and structure, and able to test orbital grade heat-shielding. The SX-2 program goal will be to demonstrate all remaining technology needed to build a reusable single-stage-to-orbit vehicle. Once SX-2 has been tested, all that should be necessary to produce a functioning reusable SSTO is to scale up the SX-2 structures and install new larger rocket engines. Proposed FY '94 funding for SX-2 startup is $75 million. The money would come out of the $3.8 billion BMDO budget already pretty much agreed on for the coming year. Total SX-2 program cost over the next three years would be very much dependent on the contractor chosen and the details of the design, but would be on the order of several hundred million. This is the same order of magnitude as typical recent X-aircraft programs such as the X-29 and X-31. SX-2 would start out under BMDO (formerly SDIO), so support from members of the House and Senate Armed Services Committees (HASC and SASC) is vital. The actual name they know SX-2 by is "followon funding for BMDO's SSRT (Single Stage Rocket Technology) program." The specific action we're calling for is for Congress to authorize $75 million in existing BMDO funding for this project next year -- we are not asking for any new funding authority, but rather for reallocation of existing funding toward a DC-X followon. Update, 22 July The SASC marked up their version of the Defence budget yesterday. Preliminary word is that SSTO was mentioned once, alongside NASP and Spacelifter, in a $30m USAF line-item. This is short of what we'd hoped for, but by no means disastrous. SSTO was at least mentioned, and on an equal (albeit underfunded) footing with NASP and Spacelifter. What this means is that we now need to go all-out on the House side, with an eye toward establishing our position there before the final House-Senate conference. With the Senate giving us very little of what we need, Representative Patricia Schroeder's HASC Research & Technology Subcommittee markup (and the full HASC markup to follow) become more important than ever. Schroeder's subcommittee is now supposed to mark up this coming Monday, the 26th. I've checked my notes, and the first "for sure" date I have for this key markup was back on May 19th, so a certain skepticism is excusable -- but at this point HASC R&T has run out of reasons for delay, as the gays-in-the- military issue has been resolved (however messily) and the Senate has already gone ahead and marked up their version of the Defense budget. Chances are that Schroeder and company really will mark, if not Monday, then at least early next week. One additional factor here: We've mentioned in the past that one appeal to make to Schroeder might be that SSRT Followon would take funding that would otherwise go to weapons development and put it to peaceful uses. Well, we need Schroeder's support real bad, and we understand she would prefer to see specific cuts in BMDO proposed to offset any new spending requested. SAS is reluctantly taking the step of picking a specific existing program within BMDO and recommending it be cut by $75 million in FY '94 in order to fund SSRT Followon within the overall $3.8 billion BMDO budget. We do not like doing this; our stated mission is to focus solely on the issue of space access. Recommending military budget cuts in areas unrelated to space access is really none of our business. Nevertheless, we're doing so. After careful consideration, we are recommending that the National Missile Defense portion of the Ground Based Radar development project (BMDO's NMD-GBR), requested at $100m for FY '94, be cut to $25m, and the $75m freed up be allocated to FY '94 funding of SSRT Followon. This is not necessarily a good program to cut, but it seems the least bad among the available options, as the somewhat complementary Theatre Missile Defense, Ground Based Radar development would remain funded at $238m. SAS members with questions or comments should contact headquarters. SAS Action Recommendations Contact Representative Schroeder plus any member of her HASC R&T Subcommittee whose district is near you by Monday morning. Ask them to fund SSRT Followon at $75m for the coming year (FY '94). Tell them that if they have to take the money out of another BMDO program, reducing the National Missile Defense portion of the Ground Based Radar project (NMD-GBR) from $100m to $25m would be the way to do so. Followup by contacting Representative Dellums (Chair, HASC) plus any member of the full HASC whose district is near you by midweek, with the same message. Keep phone calls brief, polite, and to the point - tell whoever answers that you're calling to let them know you support $75 million of BMDO (formerly SDIO) funding for the SX-2 followon to the Single Stage Rocket Technology ("SSRT") program, and that if they have to take the money out of another BMDO program, cutting the National Missile Defense portion of the Ground Based Radar project (NMD-GBR) by $75m would be one way to go. If you feel like it, throw in your favorite reason why SX-2 would be a good thing. If the person who answers wants to know more, answer their questions as best you can, otherwise thank them and ring off. Letters too should should be brief, polite, and to the point, though you can go into a bit more detail as to why a DC-X followon is good for the country. Keep it under a page and state your basic point at the start. Don't overdo it, but in general try to know who you're contacting and emphasize benefits likely to appeal to them, given their positions on the political spectrum. Future US aerospace technological competitiveness plus stemming the ongoing US loss of international space launch marketshare should appeal to just about anyone. Reusable launchers in general promise an order- of-magnitude reduction in launch costs, and SX-2 would demonstrate technologies applicable to any reusable launcher, not just Delta Clipper. Henry Vanderbilt "Reach low orbit and you're halfway to anywhere Executive Director, in the Solar System." Space Access Society - Robert A. Heinlein hvanderbilt@bix.com "You can't get there from here." 602 431-9283 voice/fax - Anonymous -- Permission granted to redistribute the full and unaltered text of this -- -- piece, including the copyright and this notice. All other rights -- -- reserved. In other words, intact crossposting is strongly encouraged. -- ------------------------------ Date: 22 Jul 1993 17:36:55 -0500 From: hvanderbilt@BIX.com Subject: DC-X Update Newsgroups: sci.space Oops. I left out this list of HASC members... List of R&T subcommittee and selected full HASC members follows. Apologies for the lack of a full HASC members list -- call your local library info desk for info on who your local Representatives are and whether they're members of House Armed Services Committee. House Armed Services Committee, Subcommittee On Research And Technology R&T Subcommittee mail address 2120 Rayburn HOB, Washington DC 20515-6041 R&T Subcommittee phone (202) 225-6527 Subcommittee Members: (all phone #'s in 202 area code, all addresses are Washington DC 20515, in either the Cannon, Longworth, or Rayburn House Office Buildings. Rep. Schroeder's address, for instance, would be written as: Representative Schroeder 2208 Rayburn HOB Washington DC 20515 ) phone fax address Patricia Schroeder, D 1 CO 225-4431 225-5842 2208 RHOB George J Hochbrueckner, D 1 NY 225-3826 225-0776 229 CHOB Owen B Pickett, D VA ? ? ? H Martin Lancaster, D 3 NC 225-3415 ? 2436 RHOB James H Bilbray, D 1 NV 225-5965 225-8808 2431 RHOB Chet Edwards, D 11 TX 225-6105 225-0350 328 CHOB Don Johnson, D 10 GA 225-4101 226-1466 226 CHOB Frank Tejeda, D 28 TX 225-1640 225-1641 323 CHOB Martin T Meehan, D 5 MA 225-3411 226-0771 1216 LHOB Jane Harman, D 36 CA 225-8220 226-0684 325 CHOB Elizabeth Furse, D 1 OR 225-0855 225-9497 316 CHOB Earl Hutto, D 1 FL 225-4136 225-5785 2435 RHOB Dave McCurdy, D 4 OK 225-6165 225-9746 2344 RHOB Bob Stump, R 3 AZ 225-4576 225-6328 211 CHOB Stephen E Buyer, R 5 IN 225-5037 225-2267 1419 LHOB Peter G Torkildsen, R 6 MA 225-8020 225-8037 120 CHOB James M Talent, R 2 MO 225-2561 225-2563 1022 LHOB Roscoe G Bartlett, R 6 MD 225-2721 225-2193 312 CHOB Duncan Hunter, R 52 CA 225-5672 225-0235 133 CHOB John R Kasich, R 12 OH 225-5355 ? 1131 LHOB James V Hansen, R 1 UT 225-0453 225-5857 2466 RHOB The following are members of the full House Armed Services Committee who are also worth contacting on this. Dellums is the full HASC Chairman, Spence is the senior HASC Republican, Lloyd, Tanner, and Geren are also on the House Space, Science, and Technology Committee, while Dornan and Cunningham are interested in SSTO. Ron Dellums, D 9 CA 225-2661 225-9817 2136 RHOB Floyd Spence, R 2 SC 225-2452 225-2455 2405 RHOB Marilyn Lloyd, D 3 TN 225-3271 225-6974 2406 RHOB John Tanner, D 8 TN 225-4714 225-1765 1427 LHOB Pete Geren, D 12 TX 225-5071 225-2786 1730 LHOB Bob Dornan, R 46 CA 225-2965 225-0275 2402 RHOB Duke Cunningham, R 51 CA 225-5452 225-2558 117 CHOB ------------------------------ Date: 22 Jul 1993 19:02:26 GMT From: Doug Mohney Subject: GPS in space (was Re: DC-1 & BDB) Newsgroups: sci.space In article <22jnuo$ptg@access.digex.net>, prb@access.digex.net (Pat) writes: > Lot's of Missions are stalled awaiting shuttle missions, >they are already authorized and funded, you move those up >into the near term. Well, no. After oh, 1997-1998, most of the manifest looks like Freedom builds. You really don't save anything, you just write checks to be spent in the Russian republic rather than the United States. >Don't confuse cash flow expeniditure for savings. the government >works on a multi year basis. Boy, that's a new one. The goverment may plan on a multi-year basis, but implementation and funding ARE on a yearly basis. Congress doesn't meet every other year, or every third year; the budget issues are fought over on a YEARLY basis. >why don't we see missions bailing off the STS for protons as we >speak. the use of russian hardware or non use of russian >hardware does not mandate the activities of other programs. > >in fact, the use of STS for SSF construction and logistics, would >most likely push science missions onto russian hardware. Pat, once again arguing with both ends of the horse. Anything that doesn't need the Shuttle is already moved off due to the post-Challenger migration. Science missions are already considering Russian launchers ... because they seem to be cheaper. >So do you think construction could take place off of Ariane 4? >or that Ariane has the reserve capacity to run logistics for SSF? >Please cite your alternative launch complex. This has already been addressed. Yes, it can be done. It isn't the cheapest method, but you can send groceries to SSF with Araine >>>A high Inclination orbit, does not require we actually >>>buy any russian flight services. it merely makes it possible. >>And adds a minimum of $400 million in extra costs. > >Are you seriously worried about half a billion dollars in DDTE >on a $ 80 Billion dollar station project? You must be joking. Pat, what a crock. It's not $80 billion, unless you use Sherzer Accounting. You get 10 years of expected funding at at a cap of $2.1 bil a year. That's $20 billion. However, to give Fred a little flame :-), $400 million in resulting performance improvements between the Al-Li tank and ASRM isn't a bad envestment no matter what orbit we end up in. >>>What can I say. THis is the one I hear a lot about. 51 degrees, >>>just about doubles the earth observations science. >> >>But does it double it in a way we care about? I don't think we can >>just measure the percentage of the Earth's surface we can see at each >>inclination and claim 'double the science'. >I have no idea on this one. Does anyone from planetary sciences know better? I hate to say it, but we've already got gonzo earth observation in "Mission to Planet Earth." And it's probably cheaper to use unmanned sats for most things as a matter of course. >>>KSC can only process N flights per year... Let's say SSF desperately needs a >>>smoke shifter, a rapid launch from Pletkesk (sp) or baikonur >>>is possible. It certainly is not from KSC. I doubt KSC could push >>>a critical launch through in less then 30 days. Pick up the phone, call Orbital Science Corp, make reservations for a couple (say quantity 4?) Taurus, solid fuel, turn around time within 30 or 60 days. Throw in a couple of heads of lettuce and some other fresh food to fill up the excess cargo space. Either the part will be mission/life critical, in which case the government will want to pay the extra expense for a "Federal Express" launch, or it won't, and can wait til the next standard resupply. >well, let's look at Skylab. moments after launch they discovered >they needed one solar array and some thermal barriers. >luckily they were able to package that onto the SKylab I flight. I see, so we are permitted to be innovative in past history, but we must be stodgy in our approaches to future problems? Tsk. >>Sounds more like an argument for more American capability rather than >>an argument for a high-inclination orbit, per se. >Please venture how much money these improvements would cost. Venture yourself Pat. If there's money to be made, OSC et al will offer up solutions for more cargo up/down well. If not, they won't. >My neighbor has on old saying. >the hard way is the easy way" You are just playing logic games. Coming from the mast-----er, that's funny. :) Especially since you are convinced that SSF won't fly. >NASA at this point in time developes nothing without a mission >to support it. ASRM and AL-LI tanks need a mission. No, both items are performance improvements to lift heavier payloads into orbit. Or lift same-sized payloads into 51.6. Going to 51.6 gives them better leverage for the hardware, but this doesn't mean thdon't need the hardware. Doug January 1993 - John Scully embraces Bill Clinton. July 1993 - Apple Computer lays off 2500 workers, posts $188 million dollar loss. -- > SYSMGR@CADLAB.ENG.UMD.EDU < -- ------------------------------ Date: Thu, 22 Jul 1993 19:53:24 GMT From: Herman Rubin Subject: Problems in space. Was: Re: Hubble SOlar Arrays, How'd they fould up. Newsgroups: sci.space In article <21JUL199321074378@judy.uh.edu> wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov writes: >In article <22kejf$ogn@access.digex.net>, prb@access.digex.net (Pat) writes... >>Everyone knows in aching detail the who's how's and whatfor's >>of the Main mirror problem of the HST. However a larger >>problem has received very little attention. That is the >>Solar Array vibration problem. THese were fabricated under >>contract to ESA by British Aerospace? and now spend >>about 20% of the mission time shaking the damn thing >>around enough that guidance is disrupted. >>What i was wondering is how could this kind of design flaw >>sneak past any sort of reasonable test procedure? I would think >>that thermal/vacuum testing would show this kind of behavior >>of the solar arrays? >>what happened. did NASA not spec out any testing? or >>did the ESA people bury the problem? >Pat some things simply cannot be tested on Earth. I happen to work >with the Marshall Solar Array guys that work on HST. The arrays were >tested at Lockheed. The whole dang thing was put in a vacuum chamber and >everything possible was done at British Aerospace, the vendors of the >array. The problem is that the thermal transient of going from light >to shadow in zero g causes a 11 Hz oscillation in the arrays. There is no >way to simulate this on earth, none at all. There is no evidence that >anyone anywhere did anything wrong. In hindsight maybe the job could have >been done differently, but it is only the on orbit experience of the >operation of the arrays that provided the information that allows them >to build better arrays this time. This is the real problem with testing things on earth. The situation is different, and not everything can be simulated. It is probably cheaper to just get out there and test things out there, with people around to deal with the unexpected. We have had many situations on earth of failures which were due to unanticipated problems; if we tested for everthing, we would do nothing except test, and we still would miss some. We often need to use the most flexible computer available, the human brain, and also to do things under the conditions which will prevail. Come up with a means to produce a sufficiently large antigravity chamber on earth, and we can do better; but since this does not seem possible, do the testing where it should be done, out there. -- Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399 Phone: (317)494-6054 hrubin@snap.stat.purdue.edu (Internet, bitnet) {purdue,pur-ee}!snap.stat!hrubin(UUCP) ------------------------------ Date: Thu, 22 Jul 1993 16:34:33 GMT From: Glenn Chapman Subject: Russian/French crew set to leave Mir space station Newsgroups: sci.space Onboard the Mir space station the Russian/French mission is preparing to depart for a landing on July 22. Long term cosmonauts Gennadiy Manakov and Aleksandr Polishchuk, who arrived at Mir on Jan. 24th, will be flying French Spationaut Jean-Pierre Haignere in the older Soyuz TM-16 capsule. Manakov and Polishchuk will have spent 174 days in orbit during this mission, while Haignere will have had 22 days in orbit. Manning the Mir complex will be cosmonauts Alexander Serebrov and Vasily Tsibliev (mission commander). They are slated to do several space walks in September to modify the power systems on the Mir space station. The International French video station TV5 has shown several news conferences with the combined Mir crew, including one with the French Prime Minister. Interestingly for most of these a huge French flag was in the backdrop. These appeared to be broadcast from one of the large Star modules extending perpendicular from the front ball docking adaptor of Mir. Views were show of the Soyuz TM-17 during from a window during one of the conferences. In other news according to a Radio Moscow report on July 19th the US and Russia reached an agreement on the selling of Russian space hardware to other countries. The problem arose over the sale of liquid hydrogen/oxygen rocket technology to India for use in an upper stage. This was considered by some to violate the missile control treaty which prevents the sale of ICBM hardware. Russia will be allowed to sell upper stages, but not the technology to build them. Another agreement was signed in Washington on July 20, for cooperation in manned space missions. This calls for the flight of a Russian cosmonaut on the space shuttle, and an 1995 visit to Mir by a US astronaut. This second agreement was being held up until the Indian export problem could be solved. (Radio Moscow and French TV5) (Sorry, a mailing problem caused Wednesday's posting of this to bounce) Glenn Chapman School Eng. Science Simon Fraser Univ. Burnaby, BC Canada ------------------------------ Date: 22 Jul 1993 18:23:52 GMT From: Doug Mohney Subject: The U.S. and Mir Newsgroups: sci.space In article <105755@hydra.gatech.EDU>, ccoprmd@prism.gatech.EDU (Matthew DeLuca) writes: > Besides, would we really want to dock Freedom to Mir? Considering the >declining state of health of the station, particularly the core module, it >doesn't seem like it would be a wise idea. We'll have a better idea of how well we can work with the Russians in 1994 and 1995 when we swap people and dock a Shuttle to Mir. Interesting irony. In 1975, we embarked the Apollo-Souyz "test flight" which put two small capsules and five men together. Twenty years later, we will bring together two larger pieces of hardware and over double the crews (say 5-7 on shuttle + 3 on Mir). Actual experiment payload is probably some large multiple of kilos higher as well. January 1993 - John Scully embraces Bill Clinton. July 1993 - Apple Computer lays off 2500 workers, posts $188 million dollar loss. -- > SYSMGR@CADLAB.ENG.UMD.EDU < -- ------------------------------ Received: from VACATION.VENARI.CS.CMU.EDU by isu.isunet.edu (5.64/A/UX-2.01) id AA12500; Thu, 22 Jul 93 16:14:28 EDT Received: from CRABAPPLE.SRV.CS.CMU.EDU by VACATION.VENARI.CS.CMU.EDU id ab20269; 22 Jul 93 17:06:57 EDT To: bb-sci-space@CRABAPPLE.SRV.CS.CMU.EDU Xref: crabapple.srv.cs.cmu.edu sci.space:67454 Newsgroups: sci.space Path: crabapple.srv.cs.cmu.edu!cantaloupe.srv.cs.cmu.edu!rochester!cornell!uw-beaver!cs.ubc.ca!fornax!glennc From: Glenn Chapman Subject: Russian/French Soyuz TM-16 mission successfully lands Message-Id: <1993Jul22.175042.1012@cs.sfu.ca> Keywords: Russian, Space, French Organization: CSS, Simon Fraser University, Burnaby, B.C., Canada Date: Thu, 22 Jul 1993 17:50:42 GMT Lines: 34 Sender: news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU The Russian/French mission to the Mir space complex successfully landed in the Soyuz TM-16 capsule this morning at 10:42 am Moscow time (0:42 am PDT) in south west central Asia. On board were the former Mir crew cosmonauts Gennadiy Manakov and Aleksandr Polishchuk, who have spent 174 days in orbit since arriving Jan. 24th, and French Spationaut Jean-Pierre Haignere (launched on July 1). The remaining crew from the July 1st Soyuz TM-17 flight, Alexander Serebrov and Vasily Tsibliev will be staying on Mir until December. Then they will be replaced by a long duration crew, with one of those Soyuz TM-18 crew members possibly staying 18 months according to some reports. For flight engineer Alexander Serebrov this will be his fourth mission: Soyuz T-7/Salyut 7 for 8 days in 1982, Soyuz T-8 for 2 days in April 1983 (making him the first human to fly on space successive missions, unfortunately shortened by a docking failure), and Sept. 1989 Soyuz TM for 167 days on board the Mir station (which saw the docking of the Kvant 2 module to Mir). He also trained for the 1987 Soyuz TM-2 but the crew was switched. His current total is 199 days of orbital work. On other point on Serebrov: he seems to have a connection with French missions. Two of his earlier flights were proceeded by Russian/French missions (Soyuz T-6 in June 1982 and Soyuz TM-7 in Nov. 1988) giving him much experience with French equipment left on the station. Lt. Col. Tsibliev is on his first flight and is the mission commander. For those of you which have it on your cable station (very common in Canada) the International French video station TV5 will probably carry the landing today. Their news time is at 4 pm (PDT) delayed about 1 hour from the original broadcast in France. Glenn Chapman School Eng. Science Simon Fraser Univ. Burnaby, BC Canada ------------------------------ End of Space Digest Volume 16 : Issue 909 ------------------------------