Date: Wed, 14 Apr 93 05:05:49 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #457 To: Space Digest Readers Precedence: bulk Space Digest Wed, 14 Apr 93 Volume 16 : Issue 457 Today's Topics: "Temporary orbits" for Mars moons? ASAT wasn't orbital (was Re: Question- Why is SSTO Single Stage) CIS air launched booster projects Comet in Temporary Orbit Around Jupiter? (2 msgs) Computer Program Will Catalog Astronomical Sky Survey How to get there? (was Re: Comet in Temporary Orbit Around Jupiter? How to get there? (was Re: Comet in Temporary Orbit Around Jupiter?) Question- Why is SSTO Single Stage Two-Line Orbital Element Set: Space Shuttle What if the USSR had reached the Moon first? Will the launch be visible from NJ? (2 msgs) 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: 13 Apr 93 20:41:35 GMT From: James Thomas Green Subject: "Temporary orbits" for Mars moons? Newsgroups: sci.space,sci.astro,alt.sci.planetary Is the "temporary orbit" theory accounting for the comet about Jupiter similar to how Demios and Phobos got captured about Mars? If not, what is different between the Comet at Jupiter and the Martian moons? /~~~(-: James T. Green :-)~~~~(-: jgreen@oboe.calpoly.edu :-)~~~\ | "I believe that this nation should commit itself to achieving | | the goal, before this decade is out, of landing a man on the | | Moon and returning him safely to the Earth." | | | ------------------------------ Date: 13 Apr 93 18:43:50 -0600 From: Bill Higgins-- Beam Jockey Subject: Newsgroups: sci.space,sci.astro,alt.sci.planetary In article <1993Apr13.205107.17581@mtu.edu>, ebgoold@mtu.edu (ERIC B. GOOLD) writes: [quoting me] >>While you're at it, comet experts, explain how a comet gets into >>Jovian orbit to begin with! > > I'm not an expert, but I'd say that it would be something like the slingshot > technique, but the opposite. Instead of stealing energy from the Jupiter-Sun > orbit it would be giving energy to it. Eric Goold and Ron Baalke both gave rational explanations for this. By the way, it sounds like breakup and non-gravitational forces have nothing to do with the capture. I guess what's bothering me is the phase space. The seat of my pants (more politely known as "my physics intuition") tells me that a comet must occupy a narrow range of velocities and nearest-approach-to-Jupiter distances in order to end up being bound to Jupiter. This seems like a very rare event, not something that would be observed two or three times in a twenty-year period. Of course, the seat of my pants has been wrong before. If cometary capture is fairly common, the phase space must be bigger than I think. I'd like somebody to tell me why. I have looked in a couple of U. Az. Press books but they refer me to books and articles not handy in the Fermilab library. The problem is connected to the origin of the Trojan asteroids. I note that some experts on this have written a book: *Long-Term Evolution of Short-Period Comets*, by Carusi, Kresak, Perozzi, and Valsecchi, published in 1985 by Adam Hilger, Ltd. Remember the Firesign Theatre radio station that broadcast "Morning Concert of Afternoon Showtime Favorites?" I don't think my interest in this matter is large enough to drive into Chicago to dig the answer out of a better library. This might change if Brian Marsden announces that the thing is definitely captured and will be around long enough for Galileo to take a peek at it! Then I will have to explain cometary capture to all my friends and relatives. Bill Higgins, Beam Jockey | "I'm gonna keep on writing songs Fermilab | until I write the song Bitnet: HIGGINS@FNAL.BITNET | that makes the guys in Detroit Internet: HIGGINS@FNAL.FNAL.GOV | who draw the cars SPAN/Hepnet: 43011::HIGGINS | put tailfins on 'em again." --John Prine ------------------------------ Date: 13 Apr 93 19:44:55 -0600 From: Bill Higgins-- Beam Jockey Subject: ASAT wasn't orbital (was Re: Question- Why is SSTO Single Stage) Newsgroups: sci.space In article <1993Apr13.145640.546@lmpsbbs.comm.mot.com>, dennisn@ecs.comm.mot.com (Dennis Newkirk) writes: [on dropping ICBMs out of airplanes...] > There was an interesting comment about this kind of launch system at the > World Space Congress last year. A military type researcher said that > technology was close or possible to allow a aircraft to be outfitted > with a propellant production plant (assumed LH and LOX) and the empty > booster. The idea is the plane takes off, fuels the missile in flight > and launches it and returns to base. This leaves no trace of propellant > production or launch facilities in the country of origin. Of course > you have to get the missile and special aircraft somewhere... This sounds like a *great* plot for a Jonny Quest episode. (No, I didn't catch the new JQ movie last week. How was it?) CAPTAIN BILL'S CHICAGO TOURS Bill Higgins See the Loop by Submarine! Fermilab Shopping? Take our convenient higgins@fnal.fnal.gov Bathyscaphe to Marshall Field's! higgins@fnal.bitnet [it's been one year since the Flood, I thought I'd use this .sig for nostalgic effect...] ------------------------------ Date: Tue, 13 Apr 1993 18:40:48 GMT From: Dennis Newkirk Subject: CIS air launched booster projects Newsgroups: sci.space Overview of current Russian work in air launched space boosters. This is by no means a complete list. References provided are quick and dirty and not comprehensive! There are many more sources and much more information available. Interim HOTOL Joint discussion on using a AN-225 (or 8 engined modification) to carry a conventionally engined British HOTOL to 10,000 meters for release. Initial studies were said to be favorable.[1] MAKS (Multipurpose Aerospace System) Gleb Lozino-Lozinsky, Gerneral Designer Molnyia NPO, is trying to sell a 250,000 kg. space plane and external tank combination, air launched from the AN-225. Named Molniya, VMS [universal reusable spacecraft], Mayak or MAKS). Unmanned payload is 8000 kg, manned 7000 kg. Propellant would be a LOX-Hydrogen-Kerosene mix using new RD-701 engine.[2] (Also See article in the latest Spaceflight magazine. This project may eventually replace ESA's Hermes) Space Clipper Proposed from the Ukraine's NPO Yuzhnoye. This would be a 3-4 stage rocket, air launched from a heavily retrofitted AN-124SC aircraft. The stages include (#1)210,000 kg, (#2)107,000 kg, (#3)21,000 kg, (#4)6000 kg, and (#5)2000 kg thrust units. Possible combinations include 1234, 2234, 234, 1235, 2235, 235. Launch time after payload integration is 10-15 hours, take-off weight from 392-365,000 kg., range to launch 7-9000 km, cruise speed 800-850 km/hr, launch altitude 10-11000 kg. Payload for 1235 is 1750 kg, 2235 is 1150 kg, 235 is 700 kg, to a 200 km circular 90 degree inclination orbit, or 1234 is 800 kg, 2234 is 485 kg, 234 is 150 kg. to a 150 x 36000 km equatorial orbit. Accuracy is 3.5 km, 2.5 sec., 2 min. inclination. Design reliability 95%. The aircraft would be equipped with air purification and thermo regulation systems to support the payload and have GPS for navigation. Launched from customers territory at appropriate azimuth for inclination. Booster is constructed from any of 5 standard sized solid rocket stages. The booster would be load on to the An-124SC at the airfield at Dnepropetrovsk would be loaded and flown to the customer for payload integration throught the front hatch of the An-124SC. Once at the launching point the booster is pulled out the back hatch on a launching cradle by parachute and once clear the parachute detaches and the rocket fires. {{Also : The SS-18 ICBM was offered for commercial space launches, conventionally launched, in 1992 by the Yuzhnoye NPO. Diameter 3 m, length 34.3 m, inside usable payload shroud diameter 2.7 to 2.52 m, and 2.91 m long (possible increase to 5.91 m). Launch weight is 210,000 kg., Payload to 200 km circular orbit at 90 degree inclination is 4000 kg. (3.5 km, 2.5 sec, 2 min inclination), propellants are nitrogen tetroxide and UDMH, first stage thrust is 460,000 kg, second stage 77,000 kg, third stage 2,800 kg.}} [4] Burlak Proposal from Russia's NPO Raduga. This would use a small all solid fuel launch vehicle air launched from a Tu-160 BlackJack bomber. It would be capable of putting about 500 Kg into LEO.[4] ---------- References [1] Kandebo, Stanley, W. "Spaceplane Conference Highlights International Hypersonic Programs." Aviation Week & ST, Nov. 12, 1990, pp. 68 [2] "International Partners for Soviet Air-Launched Spaceplane" Spaceflight, Vol. 32, May, 1990, pp. 146 [3] "Rocket Space Transportation Systems Produced by Yuzhnoye Rocket-Space Association", by YA Smetanin, IAF-92-0862, Aug, 28, 1992 [4] Wales.Larrison@ofa123.fidonet.org (Wales Larrison), "Comercial Space News #13", Tue, 28 Jan 92 01:17:21 PST, Organization: Universal Electronics Inc. (Public access BBS) ---------- Dennis Newkirk (dennisn@ecs.comm.mot.com) Motorola, Land Mobile Products Sector Schaumburg, IL ------------------------------ Date: Tue, 13 Apr 1993 22:49:23 GMT From: Henry Spencer Subject: Comet in Temporary Orbit Around Jupiter? Newsgroups: sci.space,sci.astro,alt.sci.planetary In article <1993Apr13.160004.21276@nessie.mcc.ac.uk> ft@nessie.mcc.ac.uk (Frances Teagle) writes: >This concept of a temporary orbit is new to me, what mechanism enables >a comet to break free from Jovian orbit, once is has strayed into it? Wrong question. It arrived with enough energy to escape; the question is, why does it stick around for a while? The answer is that you're trying to apply two-body intuition in an area where it breaks down. In a distant orbit around Jupiter, you cannot ignore the effect of the Sun, and you cannot just treat it as minor perturbations to a basically Jupiter-centered orbit. To get accurate results, you have to work with a three-body problem, and three-body dynamics are vastly more complex than two-body dynamics. If you insist on taking a Jupiter-centered perspective, such orbits have to be thought of as massively perturbed, unlikely to do the same thing twice in a row, and quite capable of turning into escape trajectories without warning. Throw in complications like tidal effects, the multi-body interactions in a comet nucleus that's partially broken up, and the possibility of interactions with other objects orbiting Jupiter, and it's not hard to figure out why the behavior can be very complex. -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Wed, 14 Apr 1993 01:33:53 GMT From: jgarland@kean.ucs.mun.ca Subject: Comet in Temporary Orbit Around Jupiter? Newsgroups: sci.space,sci.astro,alt.sci.planetary In article , henry@zoo.toronto.edu (Henry Spencer) writes: > In article <1993Apr13.160004.21276@nessie.mcc.ac.uk> ft@nessie.mcc.ac.uk (Frances Teagle) writes: >>This concept of a temporary orbit is new to me, what mechanism enables >>a comet to break free from Jovian orbit, once is has strayed into it? > > Wrong question. It arrived with enough energy to escape; the question > is, why does it stick around for a while? > Dance of the Planets spends a good deal of time studying the Gehrels 3 temporary capture. While it is difficult to draw the "orbit" in text, I'll try: -------_______ -------_______ -------_______ -------_______ ----___ _______ ------- __ ---__ __________---------- J_ - --- _____---------- ___________----- ___ --- ___ ____----- ____--- -----______----- Hope this helps...the above drawing is very crude, I'm afraid. For a _much_ better analysis, see Dance or some other orbital simulation package that can handle the calculations involved. The Dance manual references the book A. Carusi and G. Valsecchi, _Asteroids_ . John Garland jgarland@kean.ucs.mun.ca ------------------------------ Date: 13 Apr 1993 20:35 UT From: Ron Baalke Subject: Computer Program Will Catalog Astronomical Sky Survey Newsgroups: sci.space,sci.astro Charles Redmond Headquarters, Washington, D.C. April 13, 1993 (Phone: 202/358-1757) Jim Doyle Jet Propulsion Laboratory, Pasadena, Calif. (Phone: 818/354-5011) RELEASE: 93-067 COMPUTER PROGRAM WILL CATALOG ASTRONOMICAL SKY SURVEY Scientists at NASA's Jet Propulsion Laboratory (JPL) and the California Institute of Technology (Caltech), both in Pasadena, Calif., announced today that they have developed a computer software system to catalog and analyze the estimated half billion sky objects in the second Palomar Observatory sky survey. The survey of the northern sky includes more than 3,000 digitized photographic plates produced by Palomar, located in San Diego. Drs. Usama Fayyad and Richard Doyle of JPL said the system, called Sky Image Cataloging and Analysis Tool (SKICAT), will be delivered to Caltech this month. SKICAT is based on state-of- the-art machine learning, high performance database and image processing techniques. Caltech astronomer Professor S. Djorgovski said each photographic plate is being digitized into 23,040 by 23,040-pixel images at the Space Telescope Science Institute, Baltimore. The resulting data set will not be surpassed in quality or scope for the next decade, he said. "The sky object classification task is manually forbidding. The plates contain hundreds of millions of sky objects. Humans are unable to visually process the fainter objects in the survey," Djorgovski said. Fayyad said the core of the new system includes two integrated machine learning mathematical formulas, called algorithms. These algorithms automatically produce decision trees for the computer based on astronomer-provided training data or examples. A machine learning program learns to classify new data based on training data provided by human experts. Caltech astronomer Nick Weir and Fayyad said SKICAT has a correct sky object classification rate of about 94 percent, which exceeds the performance requirement of 90 percent needed for accurate scientific analysis of the data. By contrast, Fayyad said, the best performance of a commercially available learning algorithm was about 75 percent. By training the learning algorithms to predict classes for faint astronomical objects on the survey plates, the algorithms can learn to classify objects that actually are too faint for humans to recognize. The training data for faint objects was obtained from a limited set of charge coupled device images taken at a much higher resolution than the survey images, Weir said. The SKICAT system will produce a comprehensive survey catalog database containing about one-half billion entries by automatically processing about three terabytes (24 trillion bits, 8-bits to a byte) of image data. Since SKICAT can classify sky objects that are too faint for humans to recognize, the SKICAT catalog will contain a wealth of new information not obtainable using traditional cataloging methods, Weir said. Because sky objects up to one visual magnitude fainter now can be processed, the number of classified catalog entries will be approximately three times larger than has been possible so far with other techniques. "Some historical sky object classification tasks performed over a period of years could now be achieved in a few hours," Weir said. One major benefit of this program includes freeing astronomers from the tedium of an intensely visual and manual task so they may pursue more challenging analysis and interpretation problems, according to Djorgovski. "This is an excellent example of the use of machine learning technology to automate an otherwise infeasible task of dealing with an amount of data that is simply overwhelming to humans," Fayyad said. "SKICAT represents a new generation of intelligent trainable tools for dealing with the huge volumes of scientific image data that today's instruments collect." "We view SKICAT as a step towards the development of the next generation of tools for the astronomer of the turn of the century and beyond," Djorgovski said. -end- ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Being cynical never helps /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | to correct the situation |_____|/ |_|/ |_____|/ | and causes more aggravation | instead. ------------------------------ Date: 13 Apr 93 19:22:39 -0600 From: Bill Higgins-- Beam Jockey Subject: How to get there? (was Re: Comet in Temporary Orbit Around Jupiter? Newsgroups: sci.space,sci.astro,alt.sci.planetary In article <1993Apr13.205107.17581@mtu.edu>, ebgoold@mtu.edu (ERIC B. GOOLD) writes: >In article <1993Apr13.115437.1@fnalf.fnal.gov>, higgins@fnalf.fnal.gov (Bill Higgins-- Beam Jockey) writes: >>While you're at it, comet experts, explain how a comet gets into >>Jovian orbit to begin with! > > I'm not an expert, but I'd say that it would be something like the slingshot > technique, but the opposite. Instead of stealing energy from the Jupiter-Sun > orbit it would be giving energy to it. Eric Goold and Ron Baalke both gave rational explanations for this. By the way, it sounds like breakup and non-gravitational forces have nothing to do with the capture. I guess what's bothering me is the phase space. The seat of my pants (more politely known as "my physics intuition") tells me that a comet must occupy a narrow range of velocities and nearest-approach-to-Jupiter distances in order to end up being bound to Jupiter. This seems like a very rare event, not something that would be observed two or three times in a twenty-year period. Of course, the seat of my pants has been wrong before. If cometary capture is fairly common, the phase space must be bigger than I think. I'd like somebody to tell me why. I have looked in a couple of U. Az. Press books but they refer me to books and articles not handy in the Fermilab library. The problem is connected to the origin of the Trojan asteroids. I note that some experts on this have written a book: *Long-Term Evolution of Short-Period Comets*, by Carusi, Kresak, Perozzi, and Valsecchi, published in 1985 by Adam Hilger, Ltd. Remember the Firesign Theatre radio station that broadcast "Morning Concert of Afternoon Showtime Favorites?" I don't think my interest in this matter is large enough to drive into Chicago to dig the answer out of a better library. This might change if Brian Marsden announces that the thing is definitely captured and will be around long enough for Galileo to take a peek at it! Then I will have to explain cometary capture to all my friends and relatives. Bill Higgins, Beam Jockey | "I'm gonna keep on writing songs Fermilab | until I write the song Bitnet: HIGGINS@FNAL.BITNET | that makes the guys in Detroit Internet: HIGGINS@FNAL.FNAL.GOV | who draw the cars SPAN/Hepnet: 43011::HIGGINS | put tailfins on 'em again." --John Prine ------------------------------ Date: Tue, 13 Apr 1993 20:51:07 GMT From: "ERIC B. GOOLD" Subject: How to get there? (was Re: Comet in Temporary Orbit Around Jupiter?) Newsgroups: sci.space,sci.astro,alt.sci.planetary higgins@fnalf.fnal.gov (Bill Higgins-- Beam Jockey) writes: >In article <1993Apr13.160004.21276@nessie.mcc.ac.uk>, ft@nessie.mcc.ac.uk (Frances Teagle) writes: >> In article <6APR199314571378@kelvin.jpl.nasa.gov> baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes: >> >>>Comet Gehrels 3, which was discovered in 1977, was determined to have >>>been in a temporary Jovian orbit from 1970 to 1973. Comet Shoemaker-Levy 1993e >>>may remain in orbit around Jupiter long enough to allow Galileo to >>>make some closeup observations. The orbital trajectory for Comet >>>Shoemaker-Levy is still being determined. >> >> This concept of a temporary orbit is new to me, what mechanism enables >> a comet to break free from Jovian orbit, once is has strayed into it? > >While you're at it, comet experts, explain how a comet gets into >Jovian orbit to begin with! > Hello, I'm not an expert, but I'd say that it would be something like the slingshot technique, but the opposite. Instead of stealing energy from the Jupiter-Sun orbit it would be giving energy to it. If enough enough energy is transfered to the Jupiter-Sun orbit it won't have enough energy to escape the comet-Jupiter orbit. ACK! 3 body problems are pretty bad, it's kinda tough to treat them as a couple 2 body orbits... (Note: the Jupiter-sun orbit will not change much due to the large amount of energy associated with it... Give or take a few comets will make no difference...) Later, when the comet is in the right position/trajectory it'll get some energy back and escape... Eric Goold ------------------------------ Date: Tue, 13 Apr 1993 20:38:24 GMT From: Dave Dodson Subject: Question- Why is SSTO Single Stage Newsgroups: sci.space I think the obvious answer to the question is: Wouldn't it be silly to use the acronym SSTO, meaning "Single Stage To Orbit" for a multistage vehicle? Dave ------------------------------ Date: Tue, 13 Apr 1993 23:43:14 GMT From: TS Kelso Subject: Two-Line Orbital Element Set: Space Shuttle Newsgroups: sci.space The most current orbital elements from the NORAD two-line element sets are carried on the Celestial BBS, (513) 427-0674, and are updated daily (when possible). Documentation and tracking software are also available on this system. As a service to the satellite user community, the most current elements for the current shuttle mission are provided below. The Celestial BBS may be accessed 24 hours/day at 300, 1200, 2400, 4800, or 9600 bps using 8 data bits, 1 stop bit, no parity. Element sets (also updated daily), shuttle elements, and some documentation and software are also available via anonymous ftp from archive.afit.af.mil (129.92.1.66) in the directory pub/space. STS 56 1 22621U 93 23 A 93103.35416666 .00047945 00000-0 13817-3 0 198 2 22621 57.0042 155.1950 0004792 279.7934 331.5599 15.92686423 812 1993 023B 1 22623U 93 23 B 93103.05929260 .00066652 00000-0 19123-3 0 75 2 22623 57.0035 156.5616 0004330 275.5582 84.5080 15.92646940 754 -- Dr TS Kelso Assistant Professor of Space Operations tkelso@afit.af.mil Air Force Institute of Technology ------------------------------ Date: Tue, 13 Apr 1993 22:06:00 GMT From: Frank - Hardware Hacker - Borger Subject: What if the USSR had reached the Moon first? Newsgroups: alt.history.what-if,sci.space In article <1993Apr12.161742.22647@yang.earlham.edu>, jeffj@yang.earlham.edu (ChaOs) writes... >In article , dxb105@virgo.anu.edu.au (David Bofinger) writes: >> jeffj@yang.earlham.edu (ChaOs) writes about the military application >> of a lunar base: >> >>> Well, ever read (for example) Robert Heinlein's _The Moon is a Harsh >>> Mistress_? A lunar colony was able to do a frightening amount of >>> damage just by throwing rocks at earth. > >Just to get off the subject a bit, having _one_ computer that controlled just >about everything on the Moon from life support to transportation to calculating >flight paths means that the computer would _have_ to be tremendously complex. >That's why Mike woke up in the first place. Now back to the topic: Staying off the subject, Heinlein also miscued badly in the story saying that when Mike died, all the banks went back to using abacuses. Saw a quote the other day that if we had to replace all the computational power just used by computers in banking with humans with mechanical calculators or abacuses or whatever, it would take the entire population of the US working 40 hour weeks. Until the Russians had enough cloned 360's, PDP11's and VAX's, they didn't have the compute power to do a manned moon landing. Their main thrust (pun intended,) has been toward high-lift capabilities, near-earth expeditions, etc. There later stuff is quite sophisticated, (unmanned shuttle flight implies they had nose-wheel under computer control, something NASA isn't doing yet.) Frank R. Borger - Physicist ___ George Halas had two heirs; one carried Michael Reese - U of Chicago |___ his seed and one carried his soul. ... Center for Radiation Therapy | |_) _ One can imagine the whisper of George net: Frank@rover.uchicago.edu | \|_) Halas, rooting for his soul. - ph: 312-791-8075 fa: 791-2517 |_) Jeannie Morris ------------------------------ Date: 12 Apr 93 14:44:03 GMT From: Peter Jarvis Subject: Will the launch be visible from NJ? Newsgroups: sci.space.shuttle,sci.space In article briscoe@world.std.com (Duke Briscoe) writes: > >... I >would like to know how long after launch the solid rocket boosters and >the external tank are dropped. I was observing at about 1:35 EST or >maybe a few minutes later. > The SRB's are dropped 2 minutes and 6 secs after launch and the external tank about 8 1/2 mintes after launch. Peter Jarvis.......... ------------------------------ Date: 12 Apr 93 15:06:51 GMT From: Peter Jarvis Subject: Will the launch be visible from NJ? Newsgroups: sci.space.shuttle,sci.space In article <1993Apr9.050255.16767@nntpd.lkg.dec.com> b_egan@nac.enet.dec.com (Bob Egan) writes: > >2. after the main engine cutoff....i was VERY surprised to see the >very bright white beacons it flashed at about 2-3 second rate. >look like on on the back and one front. (or was I hullicinating ??) You may have seen attitude thrusters firing. The Shuttle has no beacons. It doesn't need them. >3. as the shuttle got further down range( east and north), I was looking up >its "rear' and watched the orange glow....if the main engine fuel burn ended at >8:40'ish...(the flash and no more bright large flame)...and the >solid rockets blew away earlier..what is the fuel for the engines at this >point ? After the ET is jettisoned, the 2 OMS engines in back are fired to get the Shuttle in the proper orbit. Depending on what orbit they are inserting into, they have 1 or 2 OMS burns to trim the orbit properly. If you saw engines burning immediately after ET jettison, then they had an OMS 1 burn followed by another later. >now..was this a "fly w/ us and see the shuttle by a departing airline >out of logan, or is this a chase plane for NASA" ???? It was probably neither. Departing airliners have dedicated routes to follow with ground controllers telling when and where to turn. As far as I know, NASA does not chase its ascending Shuttles. >.....anybody know >if the white strobes are on all through the mission? > >Bob Again, there are no strobes on the Shuttle. Peter Jarvis.......... ------------------------------ From: James Thomas Green Newsgroups: sci.materials,sci.space,poly.dept.materials Subject: Microgravity Materials Research Summary: Request for info for my Senior Project Message-Id: <1993Apr13.202752.193611@zeus.calpoly.edu> Date: 13 Apr 93 20:27:52 GMT Sender: news@zeus.calpoly.edu Organization: California Polytechnic State University, San Luis Obispo Lines: 35 Source-Info: Sender is really news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU For my senior project I'm doing a survey of the literature regarding research into microgravity materials processing. I've already got a bunch of sources but I'd like to get some more input here. What I'd like to know is: * What topics re microg materials do you consider a must-cover in a comprehensive review? * What persons and/or researchers are currently doing the "hot" research? * Who are the "historically important" persons in the field. I.e. if you write a paper on physics, you include Newton. If you write a paper on metallurgy, you include Sorby. Who are the biggies in Microg research? * While it isn't exactly "scientific", I'd like to include a few cartoons which relate to the microgravity (zero gravity) environment). If you've seen a comic strip in you newspaper, etc, I'd appreciate if you could send me a copy (or at least point out where it is so I can get it myself). My address is: James T. Green P. O. Box 4754 San Luis Obispo, CA 93403-4754 Thanks for any help you net.land folks can provide. /~~~(-: James T. Green :-)~~~~(-: jgreen@oboe.calpoly.edu :-)~~~\ | "I believe that this nation should commit itself to achieving | | the goal, before this decade is out, of landing a man on the | | Moon and returning him safely to the Earth." | | | ------------------------------ End of Space Digest Volume 16 : Issue 457 ------------------------------