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 ; Fri, 23 Nov 1990 02:05:54 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Fri, 23 Nov 1990 02:05:15 -0500 (EST) Subject: SPACE Digest V12 #586 SPACE Digest Volume 12 : Issue 586 Today's Topics: space news from Sept 17 AW&ST Re: Reliability and Insurance (3 of 3) Magellan Update - 11/20/90 Uses for LLNL Pioneer 10 Update - 11/16/90 Re: STS 38 Observation Reports HST/Saturn article Re: The Space Plane Re: STS 38 Observation Reports -- red? Re: Spectacular event over Europe 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 ---------------------------------------------------------------------- Date: 20 Nov 90 06:04:53 GMT From: wuarchive!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo!henry@decwrl.dec.com (Henry Spencer) Subject: space news from Sept 17 AW&ST Augustine commission will probably examine the question of whether the shuttle -- now seen as still an R&D vehicle -- is really suited to being the supply ship for an operational space station. Pratt&Whitney (the part of United Technologies involved in Cape York) says its success at Cape York will depend on how flexible the Bush administration is about what constitutes "fair" pricing, and in particular on adequate recognition of the need for introductory discounts to get things rolling, the legitimately low costs of Zenit production, and the cost benefits of modern launch processing. P&W has approval for an export license covering its role in the next phase of the project -- planning and financial studies -- and negotiations between the Cape York Space Agency and the USSR (delayed to permit P&W to participate) for Zenit purchases are underway. The license approval from the State Dept required restrictions on technology transfer, a commitment from the Soviets that Soviet launchers will be offered only at Cape York for ten years, and access to the details of P&W dealings with CYSA (the meaning of that last provision is still being negotiated [!]). CYSA would like P&W to invest in Cape York, but P&W has refused. The "Outreach Program" to look at innovative ideas for Moon/Mars is looking at ideas which avoid use of the space station. Ex-astronaut Tom Stafford, head of the study group, says "...when I went to the Moon and back on Apollo 10, I did not have to stop at a space station". There is wide sentiment that space-station involvement could be a drag on early stages of a return to the Moon, although Earth-orbit studies of the physiological issues would eventually be important. The AIAA, one of the major sources of input for Outreach, finds that a return to the Moon could be done by 1999 for short stays, with a more permanent outpost started by 2002. NASA will make another try to get Columbia up on Sept 18 [another hydrogen leak scuppered it], after convincing the USAF to give Astro priority over the secret Titan IV mission slated for that day. (This suggests that the Titan mission is not considered crucial to the Gulf crisis, since the USAF could have bumped the shuttle in that case.) The earlier leaks are now thought to be the result of a valve seal that was damaged when it was replaced in April as part of a check for plumbing contamination. NASA has decided to change its criteria for hydrogen leaks, based on indications that the external leak sensors are unreliable in the rather variable winds around the pads. The sensors will not be ignored, but their outputs will be treated with more caution, and TV cameras have been added to give visual confirmation (via condensation streamers) of possible leaks. The Freon leak aboard Discovery is now considered minor enough to permit Ulysses to go on schedule. The cooling system is losing about 1% of its fluid per day, and for a four-day mission NASA feels confident that just topping it up before launch will suffice. Pictures of the aftermath of the Titan SRB accident at Edwards. USAF says it will not affect current launch schedules. An SRB segment fell about 20m, slid down a hillside, ignited and burned for some time. Tentative cause is overbalancing of the crane being used to lift the segment; the crane also fell, and the boom and cable appear to have been intact at impact. One man was killed, hit by the crane. The segment was a test article, being moved as part of procedures checkout for testing of the new Hercules SRBs for the Titan. The first firing of the Hercules SRB is still scheduled for that test stand later this year, although this may slip if the accident has caused too much damage. There should be no delay otherwise; the accident is not considered to be related to the rocket hardware. Florida legislature approves funding to bring the Cape San Blas sounding- rocket site on the Gulf of Mexico back to operational status. The Florida Spaceport Authority is also interested in renovating an old pad at the Cape as a commercial orbital-launch site. It plans to fund six small sounding-rocket launches from Cape San Blas, with the payload space made available to university researchers, as a way to get things rolling there. First launch is tentatively set for late this year. Magellan is back in full communication with Earth after its conniption fit earlier, and mapping is set to start Sept 15. NASA Langley shows a segment of an elevon made entirely from carbon-carbon composite, suitable for "hot section" use in hypersonic aircraft. This is a research project not aimed at any specific vehicle, although the technology has relevance to NASP among others. They chose an elevon because it is a transition case between secondary structure and primary structure, and it involves various interesting fabrication problems. This is the first large carbon-carbon structural component built anywhere (at least, the first not classified!). -- "I don't *want* to be normal!" | Henry Spencer at U of Toronto Zoology "Not to worry." | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 19 Nov 90 16:03:20 GMT From: mentor.cc.purdue.edu!mace.cc.purdue.edu!dil@purdue.edu (Perry G Ramsey) Subject: Re: Reliability and Insurance (3 of 3) In article <1990Nov17.214659.23993@zoo.toronto.edu>, henry@zoo.toronto.edu (Henry Spencer) writes: > In article <8746@fmeed1.UUCP> russ@m-net.ann-arbor.mi.us (Russ Cage) writes: > >>... the OPF bottleneck is reduced by merely eliminating the redundant > >>system checks to ensure the first checkout was correct.) > > > >Considering how complex Shuttle is, this sounds like a really > >*bad* idea from where I stand. The reliability achieved by > >the Shuttle software group is due to their checkout procedures. > > The question is, how much *extra* reliability is bought by all those extra > checks? Wales is suggesting that it approaches zero; I am inclined to agree. > -- > "I don't *want* to be normal!" | Henry Spencer at U of Toronto Zoology At first, all that checking probably does buy you close to zero added reliability. After everyone gets used to the system, it probably makes things worse. The guy doing the job is less inclined to bust his buns making sure it's right, because, after all, there are three quality control checkers who will inspect the work after he's finished. On top of that, he doesn't have time to make sure the hardware is right -- he has too much paperwork to do! Three QC inspectors signed off that the work platform had been removed from the orbiter. You remember, the one they found when it went "KLUNK" as the orbiter was being mated to the ET. It would have only taken one person to take that thing out. The fact that four didn't is at least one data point against the notion that more bodies are always better than fewer. Paperwork and independent checking are essential to making complicated machinery work, but everyone has forgotten that their only value is as an aid in ensuring that the work is done right. They are not a substitute for it. -- Perry G. Ramsey Department of Earth and Atmospheric Sciences perryr@vm.cc.purdue.edu Purdue University, W. Lafayette, IN USA dil@mace.cc.purdue.edu Why waste time learning when ignorance is instantaneous? -- Hobbes ------------------------------ Date: 20 Nov 90 21:51:52 GMT From: csus.edu!wuarchive!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ucdavis.ucdavis.edu (Ron Baalke) Subject: Magellan Update - 11/20/90 MAGELLAN STATUS REPORT November 20, 1990 The Magellan spacecraft is performing nominally in mapping mode, and has just completed its 376th mapping orbit. The two DESATS (desaturations of the reaction wheels) and 7 STARCALS (star calibrations) of the past 24 hours were successful, with all attitude updates less than 0.02 degrees. Today, a backfill of AACS (Attitude and Articulation Control Subsystem) memory B will be sent to the spacecraft and played back to test for corrupted memory cells. Tonight, mapping sequence M0325 and its associated parameter files will be uploaded. The radar system is performing nominally. Three orbits of data using the new data management strategy which avoids tracks A2 and A4, have been analyzed and appear to be the the most error-free to date. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ Date: 20 Nov 90 16:45:04 GMT From: usc!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!src.honeywell.com!msi.umn.edu!cs.umn.edu!kksys!orbit!pnet51!schaper@ucsd.edu (S Schaper) Subject: Uses for LLNL Hmm, if it is that cheap, why not a major corp, like Bendix, put their corporate HQ up in space outside of tax jurisdiction, a variation of the old =buy an island' concept. 1/2 :-) ************************************************************************** Zeitgeist Busters! UUCP: {amdahl!bungia, uunet!rosevax, chinet, killer}!orbit!pnet51!schaper ARPA: crash!orbit!pnet51!schaper@nosc.mil INET: schaper@pnet51.cts.com ------------------------------ Date: 21 Nov 90 00:54:42 GMT From: snorkelwacker.mit.edu!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@bloom-beacon.mit.edu (Ron Baalke) Subject: Pioneer 10 Update - 11/16/90 PIONEER 10 STATUS REPORT November 16, 1990 A precession maneuver, scheduled for December 16 has been cancelled. Due to the increase in angular acceleration of the spacecraft and limited tracking, the roll phase analysis has been unsuccessful in producing a reliable data base for predicting the roll phase. These data, obtained during two-way tracking, are required for planning the maneuver. As a result, the Earth Look Angle (ELA) will increase to a maximum of 1.1 degrees during February and March, 1991, and then drift back down to below 1.0 degrees. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ Date: 19 Nov 90 17:11:12 GMT From: rex!rouge!dlbres10@ames.arc.nasa.gov (Fraering Philip) Subject: Re: STS 38 Observation Reports Could it be that the reddish color comes from the fact that the shuttle is being illuminated by sunlight which has passed through the atmosphere, i.e. during 'orbital sunset?' Phil ------------------------------ Date: 21 Nov 90 21:34:14 GMT From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ucsd.edu (Ron Baalke) Subject: HST/Saturn article The Philadelphia Inquirer (AP) 11/21/90 By Harry F. Rosenthal Photos of Saturn show huge storm "The Hubble Space Telescope has returned pictures of a remarkable event on Saturn, a storm that has grown from an Earth-sized white dot to a girdle around the planet with ammonia clouds billowing 150 miles high." The story quotes Cal-Tech planetary scientist Andrew Ingersoll, "It just might me the largest atmospheric structure right now in the solar system, outside of the sun." The storm was discovered by amateur astronomers in September when it was three times the diameter of Earth according to the article. The Hubble telescope, though hampered by a faulty mirror, was directed a Saturn Nov. 9 and 11 and last weekend as the storm enlarged to ring the planet with swirls and loops in a band 6,000 miles wide, the report states. NASA Headquarter's Director of Astrophysics Charles Pellerin said that a film would be made of the 400 pictures take so far to depict the evolution of the "storm of the century." The article continues, saying that though astronomers do not know the cause of the storm, Ingersoll discounted the possibility that a comet or other celestial object struck the planet to cause the disturbance."It has to be some sort of internal intermittent thing on Saturn, like Saturn burped. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ Date: 20 Nov 90 02:15:13 GMT From: rochester!sol!yamauchi@pt.cs.cmu.edu (Brian Yamauchi) Subject: Re: The Space Plane In article <1990Nov19.171142.12793@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes: the military is not very big on hypersonics either (at least, not unclassified ones: there is speculation that a good bit of the X-30 work may be a duplication of "black" programs which already have flying hardware). Are you talking about Aurora (a rumored Mach 5 (?) reconnaissance aircraft), or about something different? If the X-30 works really well, a successor might be a useful Earth-to-orbit transport, but that is 15-20 years away, minimum, at the current pace. According to Aviation Week, if Congress approves building the X-30 in 1993, the first flight would be in 1997, and the first single-stage-to-orbit test would be in 1999. So, I suppose the relevant questions are: (1) Will the X-30 keep to its schedule? (2) After a successful orbital flight, how long will it take to develop a passenger or cargo carrying version? (3) Will the resulting passenger/cargo vehicle be commercially viable, or will it be another shuttle (technologically successful, but too maintenance intensive to be economical). -- _______________________________________________________________________________ Brian Yamauchi University of Rochester yamauchi@cs.rochester.edu Computer Science Department _______________________________________________________________________________ ------------------------------ Date: 20 Nov 90 18:48:26 GMT From: agate!stew.ssl.berkeley.edu!korpela@ucbvax.Berkeley.EDU (Eric J. Korpela) Subject: Re: STS 38 Observation Reports -- red? In article <4900@optilink.UUCP> cramer@optilink.UUCP (Clayton Cramer) writes: >In article <1990Nov19.063120.15680@ns.network.com>, logajan@ns.network.com (John Logajan) writes: >> molczan@gpu.utcs.utoronto.ca (Ted Molczan) writes: ># Pardon my ignorance, but isn't it possible that the red color is due ># to the same thing that occasionally gives red sunrises and sunsets? >No. The red color at sunrise and sunset is caused by the atmosphere. >There's no atmosphere where the shuttle is; unless you are observing >the shuttle at a very flat angle to the horizon, you aren't going >to see red. I disagree. You seem to be missing the point that it is sunlight that is illuminating the shuttle. As the shuttle nears the shadow, the path length through the atmosphere of the illuminating sunlight becomes long. The blue light is scattered out before it even reaches the shuttle. This could be responsible for the change in color as the shuttle nears the shadow. /\ korpela@sunspot.ssl.berkeley.edu Internet /__\ rioch BKYAST::KORPELA 42215::KORPELA DecNet / \ of Chaos korpela%bkyast@ucbjade Bitnet (_____________________ ------------------------------ Date: 19 Nov 90 08:40:44 GMT From: mcsun!cernvax!chx400!ugun2b!ugun2a!pfennige@uunet.uu.net Subject: Re: Spectacular event over Europe In article <1377@mpirbn.mpifr-bonn.mpg.de>, p515dfi@mpirbn.mpifr-bonn.mpg.de (Daniel Fischer) writes: > In article <816@obs.unige.ch> pfenniger@obs.unige.ch writes: >>A spectacular event occurred on Nov. 5, around 18h UT (19h local time) over a >>large part of western Europe. Something similar to a big meteorite or >>satellite atmospheric reentry has been observed by thousands of people [...] >>Could someone with connection to NASA, NORAD tells if the satellite hypothesis >>can be rejected ? Such a large orbiting object should have been tracked.[...] > > It *was* a reentry: NORAD has distributed the news that the event was caused by > the reentry & burnup of the upper stage of the rocket that carried the Soviet > comsat GORIZONT 21 into orbit on 3 October. Experienced observers on the ground > had guessed that fact already from the long duration of the phenomenon, 2 to 3 > minutes: even a really big meteor (like the one from 1972 or the recent Euro- > meteor from Sept.1986) crosses the sky in a few seconds. > > [Sources: communication with D.Heinlein, Europ. Net for Meteor Cameras + AP] I don't think that one can safely distinguished between the two options from the apparent velocity differences alone. It is true that a couple of second event rules out a normal satellite, but a longer one doesn't rule out a meteorite. First, a meteor has a relative velocity with the earth typically of the order of 3-4 times larger than a satellite (30 km/s versus 8 km/s), while the timings from people varied between minutes and ~10 seconds. Even at 70 km/s, a meteor needs not a few seconds, but more than about 20 seconds to cross the sky, at 100-150 km altitudes in nearly circular trajectory, as implied by the locations of observers over an arc of at least 1300 km. Second, in the evening a meteor has to overtake the Earth on its orbit, which selects out the meteors in the solar system moving faster than 30km/s in the direct sense; the resulting relative velocity can be as low as one wants. It is thus not unreasonable to expect slow (~10 km/s) meteors at 19h. In the morning it would have been the opposite. Third, a journalist told us that the Munich group of experienced observers (leaded by Heinlein) had first proposed the meteorite option and sent this news to AFP (Agence France Press). So experienced observers can be mislead. A last reason in favor of the meteor option was that no warning had been given to the press, which was usual in the past for big space junk (Skylab etc.), and also that the answer did take quite a while (more than a week) to reach the media. In retrospect, the strongest argument in favor of the artificial body was the nearly west->east circular orbit implied by the observations, the most frequent sense of circulation of artificial satellites. Daniel Pfenniger, Geneva Observatory ------------------------------ End of SPACE Digest V12 #586 *******************