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 Mar 90 02:32:49 -0500 (EST) Message-ID: <0ZzTC7G00VcJE2HU4j@andrew.cmu.edu> Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Wed, 14 Mar 90 02:32:23 -0500 (EST) Subject: SPACE Digest V11 #146 SPACE Digest Volume 11 : Issue 146 Today's Topics: Re: Resolving Power of Hubble Space Telescope Re: Sci. Am. Lunar Telescope Article Re: SR-71 at Smithsonian Re: Resolving Power of Hubble Space Telescope Re: environmental impact of antimatter rockets NASA Position in Intelligent Systems Repost of "High Flight" Re: Subscription to AW&ST in UK ? Voyager and other probes Re: Challenger last words Re: SR-71 at Smithsonian ---------------------------------------------------------------------- Date: 14 Mar 90 04:31:42 GMT From: cs.utexas.edu!samsung!aplcen!haven!uvaarpa!hudson!astsun8.astro.Virginia.EDU!gsh7w@tut.cis.ohio-state.edu (Greg S. Hennessy) Subject: Re: Resolving Power of Hubble Space Telescope In article <1990Mar14.011428.17553@agate.berkeley.edu> daveray@sag4.ssl.berkeley.edu (David Ray) writes: #OK, so the HST optics have resolving power of 0.1 arcseconds. # ^^^^^^ #Now, what about the spacecraft? We will find out in a few months. The documentation I have seemed to state that there was a design goal of 0.07 arc jitter. I can recheck my references if it is important enough. Note: this was the spec, we don't know what it will do (yet). #It is my understanding that this 0.1 arcsecond requirement #is the most stringent attitude control requirement of all spacecraft #history. Is this true? Yep, and one of the reasons HST was so expensive. It is HARD doing that accuracy. #1. Whenever anything moves on the spacecraft, such as filter wheels # on the focal plane, electrical relays tripping, etc., this "shakes" # the spacecraft, and I assume more than 0.1 arcseconds. How is this # handled? Does one wait for the atitude "jitter" to dampen, and then # start to take data? I know some of the filter wheels have counter wheels. I think some don't. -Greg Hennessy, University of Virginia USPS Mail: Astronomy Department, Charlottesville, VA 22903-2475 USA Internet: gsh7w@virginia.edu UUCP: ...!uunet!virginia!gsh7w ------------------------------ Date: 13 Mar 90 17:41:54 GMT From: news-server.csri.toronto.edu!utgpu!watserv1!watdragon!watyew!jdnicoll@rutgers.edu (Brian or James) Subject: Re: Sci. Am. Lunar Telescope Article Well, the light diffusion could come from booster pollution (or lunar factory pollution) and the light source for the odd shadows *might* be from a nearby antimatter powered shuttle exploding. JDN PS: See original article for smilies. ------------------------------ Date: 13 Mar 90 21:09:11 GMT From: skipper!shafer@ames.arc.nasa.gov (Mary Shafer (OFV)) Subject: Re: SR-71 at Smithsonian In article <1990Mar13.165706.494@murdoch.acc.Virginia.EDU> gl8f@astsun.astro.Virginia.EDU (Greg Lindahl) writes: >As of yesterday it [SR-71] was sitting outdoors at Dulles, and you can see it >from one of the terminals. Has red paint (?) over the windows so that >you can't see inside. The red things are shields. They're on the windows, the inlet doors, the inlet, and something on the turtleback, behind the cockpit. There are also red shields or covers on the air data system, including angle-of-attack vanes. -- Mary Shafer shafer@skipper.dfrf.nasa.gov or ames!skipper.dfrf.nasa.gov!shafer NASA Ames Dryden Flight Research Facility, Edwards, CA Of course I don't speak for NASA ------------------------------ Date: 14 Mar 90 01:14:28 GMT From: agate!sag4.ssl.berkeley.edu!daveray@ucbvax.Berkeley.EDU (David Ray) Subject: Re: Resolving Power of Hubble Space Telescope OK, so the HST optics have resolving power of 0.1 arcseconds. ^^^^^^ Now, what about the spacecraft? This may be a moot point, but I am curious about the attitude control (i.e. pointability) of the HST spacecraft. It is my understanding that this 0.1 arcsecond requirement is the most stringent attitude control requirement of all spacecraft history. Is this true? Just curious, does anyone have any information on the attitude control plan for the HST spacecraft? I speculate the following scenarios: 1. Whenever anything moves on the spacecraft, such as filter wheels on the focal plane, electrical relays tripping, etc., this "shakes" the spacecraft, and I assume more than 0.1 arcseconds. How is this handled? Does one wait for the atitude "jitter" to dampen, and then start to take data? 2. In order to know that the spacecraft attitude is within the 0.1 arcsecond (or whatever) allocation, a separate, independent system such as a star tracker or inertial tracking system must be used. What is planned to be used and what is its sensitivity? I posted this question some time ago and noone responded. Does anyone have information on this? Dave Ray daveray%ssl@jade.berkeley.edu Space Sciences Laboratory UC Berkeley ------------------------------ Date: 13 Mar 90 17:29:00 GMT From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: environmental impact of antimatter rockets In article <1990Mar12.152129.1254@helios.physics.utoronto.ca> neufeld@physics.utoronto.ca (Christopher Neufeld) writes: > ... I thought that a 280kT blast every second, >for a couple of minutes, in a rising column would produce a firestorm of >sufficient size to extend the range of the damage considerably beyond that >of a single explosion... If it goes straight up, which would be the sensible thing to do, damage should remain fairly localized. One would assume that sane planners would put the launch site somewhere well away from inhabited areas, minimizing the number of things that could be ignited. The ability of nuclear explosions to cause fires in non-urban areas is vastly exaggerated; the only detailed study I've seen (which was looking at the nuclear-winter aspects) concluded that croplands and wildlands simply aren't very flammable most of the time. Croplands burn well only when the crops are dry, just before harvest, and the times are staggered so it's rare for large areas to be flammable at one time. Localized forest fires would be a possibility, but conditions conducive to major spreading of forest fires are quite rare. Seasonal variation is considerable, too: if you launched from a northern area in winter, the problem would be pretty much nonexistent. Finally, just to be picky :-), a firestorm (as opposed to widespread fires) requires a precise set of conditions and isn't that easy to do even when you are deliberately trying. After the Hamburg firestorm was understood, practically every major WW2 bombing operation tried to raise a firestorm, and only the Dresden raids succeeded. (Okay, for those who are puzzled by this: a firestorm is not just a big fire or a whole bunch of fires. It's a very specific phenomenon in which a large area is ignited at about the same time, the updraft from the fires creates an inward wind, the wind fans the flames, and, um, positive feedback goes to completion, stopping only when there is nothing left to burn. It's immensely destructive but doesn't get started easily; in particular, even a gentle breeze will prevent it.) -- MSDOS, abbrev: Maybe SomeDay | Henry Spencer at U of Toronto Zoology an Operating System. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 13 Mar 90 18:14:03 GMT From: ptolemy!sliwa@eos.arc.nasa.gov (Nancy E. Sliwa) Subject: NASA Position in Intelligent Systems **************** Job Announcement - Branch Chief National Aeronautics and Space Administration Ames Research Center The Information Sciences Division is seeking applicants to lead the Intelligent Systems Technology Branch. The branch chief serves as the technical and administrative head of 30 personnel engaged in research and development of high performance intelligent computational systems for aerospace missions. Current branch projects include parallel processing systems (particularly software infrastructure for symbolic applications), dependable systems including fault management and software testing, analog optical information processing, neural networks, multiprocessing architectures, and network analysis. Applicants should hold a PhD degree or equivalent experience, have demonstrated the ability to lead and supervise, and have published articles in the field of computer architectures. Salaries are from $59,215 to $76,982. U.S. Citizenship is required. Ames Research Center, located in the San Francisco/San Jose area, is an equal opportunity/affirmative action employer. Send a detailed resume and publications list to: Dr. Ellen Ochoa NASA Ames Research Center MS 244-4 Moffett Field, CA 94035 (415) 604-6725 ****************** ------------------------------ Date: 13 Mar 90 20:56:56 GMT From: rpi!pawl5.pawl.rpi.edu!sundance@tcgould.tn.cornell.edu (Mitchell E. Gold) Subject: Repost of "High Flight" While searching through some old boxes, I found my program book from "The Right Stuff" (Warner Bros.,1983). The words from High Flight are listed therein with the following: John Gillespie Magee, Jr. Pilot Officer Magee joined the Royal Canadian Air Force in October 1940, at age 18. He went to England to fly Spitfires. After qualifying, he was piloting one on a test flight into the stratosphere at 30,000 feet when he got the inspiration for "High Flight." Magee was killed in action during a dogfight December 11, 1941, at age 19. Oh, I have slipped the surly bonds of earth And danced the skies on laughter-silvered wings; Sunward I've climbed, and joined the tumbling mirth Of sun-split clouds -- and done a hundred things You have not dreamed of -- wheeled and soared and swung High in the sunlit silence. Hov'ring there, I've chased the shouting wind along, and flung My eager craft through footless halls of air. Up, up the long, delirious, burning blue I've topped the windswept heights with easy grace Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod The high untrespassed sanctity of space, Put out my hand, and touched the face of God. The final quote in the program book is by Gus Grisso. "If we die, we want people to accept it. We hope that if anything happens to us it will not delay the program. The conquest of space is worth the risk of life." -- Mitchell Gold \|/ @ The RPI Solarium Rensselpolyinstitechnitute -*- Troy, NY, USA /|\ sundance@pawl.rpi.edu ------------------------------ Date: 13 Mar 90 21:25:46 GMT From: skipper!shafer@ames.arc.nasa.gov (Mary Shafer (OFV)) Subject: Re: Subscription to AW&ST in UK ? In article <1031@vision.UUCP> simon@vision.UUCP (Simon Taylor) writes: >Does anyone know where one can get hold of Aviation Week in the UK ? Subscribe to Flight International instead. It's better, you'll get it sooner, and it's got Uncle Roger in Straight and Level! -- Mary Shafer shafer@skipper.dfrf.nasa.gov or ames!skipper.dfrf.nasa.gov!shafer NASA Ames Dryden Flight Research Facility, Edwards, CA Of course I don't speak for NASA ------------------------------ Date: 13 Mar 90 15:21:47 GMT From: eru!luth!sunic!mcsun!ukc!kl-cs!nott-cs!piaggio!mew@BLOOM-BEACON.MIT.EDU (Mark E Wickett) Subject: Voyager and other probes I don't know if this question has been asked before, but how exactly does NASA communicate with their probes? I presume it's some sort of radio broadcast, but it must be encoded etc. Would it be possible for someone else to send stuff to these probes to perform some action? It may a load of dumb questions, but I'm interested in the answers anyway. Mark -- Mark Wickett - mew@maths.nott.ac.uk | What the hell do I know? - mew@cs.nott.ac.uk | I'm English! ------------------------------ Date: 13 Mar 90 18:50:04 GMT From: ladcgw!hermes!fmayhar@uunet.uu.net (Frank Mayhar) Subject: Re: Challenger last words In article <900312.09172868.038053@RMC.CP6>, JC@RMC.BITNET writes: > In article <3271@viper.Lynx.MN.Org> dave@viper.Lynx.MN.Org (David Messer) > writes: > >Yes, the last words recorded were: "No, I wanted a BUD Light!" :-) > You are quite a jerk, aren't you ? > John Coughlin Net: JC@RMC.BITNET Vox: 613-541-6439 Fax: 613-547-3053 Well, _I_ thought it was at least mildly amusing. A product of a sick mind, maybe, but amusing. -- Frank Mayhar fmayhar@hermes.ladc.bull.com (..!{uunet,hacgate}!ladcgw!fmayhar) Bull HN Information Systems Inc. Los Angeles Development Center 5250 W. Century Blvd., LA, CA 90045 Phone: (213) 216-6241 ------------------------------ Date: 13 Mar 90 16:57:06 GMT From: cs.utexas.edu!wuarchive!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!haven!uvaarpa!murdoch!astsun.astro.Virginia.EDU!gl8f@tut.cis.ohio-state.edu (Greg Lindahl) Subject: Re: SR-71 at Smithsonian In article <9003122348.AA08559@cmr.ncsl.nist.gov> roberts@CMR.NCSL.NIST.GOV (John Roberts) writes: >Question: Is it possible for the general public to see Enterprise/SR-71 >now, or will we have to wait until the official opening of the annex? As of yesterday it was sitting outdoors at Dulles, and you can see it from one of the terminals. Has red paint (?) over the windows so that you can't see inside. My spy also ran into someone claiming to be an ex-SR-71 pilot near a display inside the airport. Gee, when a program gets declassified, it really gets declassified :-) Greg Lindahl gl8f@virginia.edu Astrophysicists for Choice. ------------------------------ End of SPACE Digest V11 #146 *******************