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/usr1/ota/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl) (->ota+space.digests) ID ; Thu, 14 Sep 89 19:50:02 -0400 (EDT) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Thu, 14 Sep 89 19:49:25 -0400 (EDT) Subject: SPACE Digest V10 #40 SPACE Digest Volume 10 : Issue 40 Today's Topics: Re: Was Voyager another damaging Apollo one-shot? NASA Prediction Bulletin Format Re: Apollo 8, 9, and 10 Voyager Status for 07/18/89 (Forwarded) NASA awards grants for future exploration studies (Forwarded) Re: Neptune fly-by ---------------------------------------------------------------------- Date: 2 Sep 89 11:48:52 GMT From: b.gp.cs.cmu.edu!Ralf.Brown%B.GP.CS.CMU.EDU@pt.cs.cmu.edu Subject: Re: Was Voyager another damaging Apollo one-shot? In article <14616@bfmny0.UUCP>, tneff@bfmny0.UUCP (Tom Neff) wrote: >be hard to come by. I'm just a little afraid that NASA has managed to >outsmart itself by doing such a comprehensive job with a couple of >probes. Granted, they managed to do an incredible job with a single half-crippled spacecraft*. But.... The original "Grand Tour" concept (killed by lack of funding) was for two probes to fly Jupiter-Saturn-Pluto, and two probes to fly Jupiter-Uranus-Neptune (or was it J-S-U-N?). The first two probes would be arriving at Pluto just about now . Voyager started as Mariner Jupiter-Saturn. Voyager 2 continuing on to Uranus and Neptune was only a possibility if Voyager 1 performed flawlessly at Saturn, which it luckily did. * the litany of failures: primary receiver dead backup receiver tracking loop capacitor failed. As a result, V2 can only receive on an extremely narrow band, which changes with the craft's internal temperature. Not only do the controllers have to compute the frequency at which their signal arrives (the earth's rotation is enough to doppler-shift the signal out of the receive window!), but they also have to guess at where the receive window *is*. photopolarimeter spectrometer nearly burned out (human error, it was left pointing at a bright calibration plate while set to highest sensitivity) a filter wheel which stuck several times narrow-angle camera's sensitivity fading stuck bit in the memory for the computer doing the image compression scanning platform seized up at Saturn, could no longer be used at the high slew rate, and only limited use at the medium speed to prevent another seizure. There may be other problems which I don't recall off-hand. There were also problems on the ground. That they managed to get so many good results anyway is a real tribute to the Voyager team's skill and dedication. -- UUCP: {ucbvax,harvard}!cs.cmu.edu!ralf -=-=-=-=- Voice: (412) 268-3053 (school) ARPA: ralf@cs.cmu.edu BIT: ralf%cs.cmu.edu@CMUCCVMA FIDO: Ralf Brown 1:129/46 FAX: available on request Disclaimer? I claimed something? You know it's going to be a bad day when... ...your birthday cake collapses from the weight of the candles. ...you wake up face down on the pavement. ------------------------------ Date: 5 Sep 89 04:55:50 GMT From: ncis.tis.llnl.gov!blackbird!tkelso@lll-winken.llnl.gov (TS Kelso) Subject: NASA Prediction Bulletin Format As a service to the satellite user community, the following description of the NASA Prediction Bulletin's two-line orbital element set format is uploaded to sci.space on a monthly basis. The most current orbital elements from the NASA Prediction Bulletins are carried on the Celestial RCP/M, (513) 427-0674, and are updated several times weekly. Documentation and tracking software are also available on this system. The Celestial RCP/M may be accessed 24 hours/day at 300, 1200, or 2400 baud using 8 data bits, 1 stop bit, no parity. ============================================================================== Data for each satellite consists of three lines in the following format: AAAAAAAAAAA 1 NNNNNU NNNNNAAA NNNNN.NNNNNNNN +.NNNNNNNN +NNNNN-N +NNNNN-N N NNNNN 2 NNNNN NNN.NNNN NNN.NNNN NNNNNNN NNN.NNNN NNN.NNNN NN.NNNNNNNNNNNNNN Line 1 is a eleven-character name. Lines 2 and 3 are the standard Two-Line Orbital Element Set Format identical to that used by NASA and NORAD. The format description is: Line 2 Column Description 01-01 Line Number of Element Data 03-07 Satellite Number 10-11 International Designator (Last two digits of launch year) 12-14 International Designator (Launch number of the year) 15-17 International Designator (Piece of launch) 19-20 Epoch Year (Last two digits of year) 21-32 Epoch (Julian Day and fractional portion of the day) 34-43 First Time Derivative of the Mean Motion or Ballistic Coefficient (Depending on ephemeris type) 45-52 Second Time Derivative of Mean Motion (decimal point assumed; blank if N/A) 54-61 BSTAR drag term if GP4 general perturbation theory was used. Otherwise, radiation pressure coefficient. (Decimal point assumed) 63-63 Ephemeris type 65-68 Element number 69-69 Check Sum (Modulo 10) (Letters, blanks, periods = 0; minus sign = 1; plus sign = 2) Line 3 Column Description 01-01 Line Number of Element Data 03-07 Satellite Number 09-16 Inclination [Degrees] 18-25 Right Ascension of the Ascending Node [Degrees] 27-33 Eccentricity (decimal point assumed) 35-42 Argument of Perigee [Degrees] 44-51 Mean Anomaly [Degrees] 53-63 Mean Motion [Revs per day] 64-68 Revolution number at epoch [Revs] 69-69 Check Sum (Modulo 10) All other columns are blank or fixed. Example: NOAA 6 1 11416U 86 50.28438588 0.00000140 67960-4 0 5293 2 11416 98.5105 69.3305 0012788 63.2828 296.9658 14.24899292346978 Note that the International Designator fields are usually blank, as issued in the NASA Prediction Bulletins. -- Dr TS Kelso Asst Professor of Space Operations tkelso@blackbird.afit.af.mil Air Force Institute of Technology ------------------------------ Date: 15 Aug 89 13:46:48 GMT From: grits!ddavey@bellcore.com (Doug Davey) Subject: Re: Apollo 8, 9, and 10 In article <1989Jul19.005449.3163@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes: > orbit, Apollo 10 flew a dress rehearsal of the landing (including LM > descent to 10 miles above the Moon), and Apollo 11 was the big one. The line that sticks in my mind from Apollo 10 was: "We're really down among 'em!" It must have been quite a sight to be in orbit, but be only 10 miles above the surface. Does anybody remember whether the ascent or descent engine was used during Apollo 10's return from low orbit to rendezvous with the CSM? Either option seems difficult. On the one hand, I would not expect the descent engine to be restartable. On the other, firing the ascent engine and getting the ascent stage cleanly separated from the descent stage would be tricky since the descent stage was deigned to be firmly on the lunar surface during this operation. | ___ ___ ___ ___ __ ___ Doug Davey | /__/ /__ / / / / / /__) /__ bellcore!rruxi!ddavey | /__/ /__ /__ /__ /__ /__/ / \ /__ | ------------------------------ Date: 15 Aug 89 17:46:55 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: Voyager Status for 07/18/89 (Forwarded) Voyager Status Report July 18, 1989 Neptune's new moon, 1989 N1, is becoming a new guidepost for the Voyager navigation team and is a candidate to help better determine the location of Neptune itself. Neptune was discovered in 1846, and the planet takes 165 years to orbit the Sun; thus, Neptune won't return to the position where astronomers first saw it until 2011. This leaves great uncertainty in the precise knowledge of Neptune's orbit that Voyager navigators need to get the spacecraft to the targeted area of the planet at the right time. But the new Neptunian moon, 1989 N1, will provide the navigation team with a better idea of Neptune's exact location. The discovery of the moon fulfilled expectations of Voyager navigators who were hoping to find at least one new object in the Neptune system whose orbit could potentially be used to gauge the relative positions of Triton, Neptune and various background stars, said Don Gray, Voyager Navigation Team Chief. Many of the images coming back from the spacecraft are optical navigation frames. Ideally, the frames show a moon against a field of stars. Using stars as dim as 10th magnitude as reference points, the Voyager navigators progressively update and refine the location of Neptune and its moons. This new information is then integrated into commands that adjust Voyager's flight path and retarget the spacecraft's observations, if necessary. The next trajectory correction maneuver is being designed and will be uplinked to the spacecraft late next week. The maneuver is one of the final three that will be conducted between now and closest approach to bring the spacecraft within about 100 miles (150 kilometers) of the point at which it's aimed -- about 3,000 miles (4,850 kilometers) from Neptune's cloud tops. DISTANCE TO EARTH: 2,686,949,000 miles DISTANCE TO NEPTUNE: 33,805,000 miles HELIOCENTRIC VELOCITY: 42,192 mph ------------------------------ Date: 15 Aug 89 19:53:30 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: NASA awards grants for future exploration studies (Forwarded) Edward Campion July 18, 1989 Headquarters, Washington, D.C. RELEASE: 89-118 NASA AWARDS GRANTS FOR FUTURE EXPLORATION STUDIES NASA's Office of Exploration has awarded a series of study contracts to various organizations to provide NASA with ideas, concepts, devices, systems, trajectories, operations or implementations which could be applied to furthering human exploration of the solar system. The 20 winners, selected from 115 proposals submitted in response to the April 12, 1989, NASA Research Announcement, are located in 12 different states and come from various occupations with five industry-related firms, two space support-related organizations and 13 universities receiving awards. In selecting the winners, the criteria applied to all the submissions was the experience of the principal investigator, the relevance of the proposal to programs of human exploration of the solar system, the performance improvement or complexity reduction possibilities and the uniqueness of the idea or concept. Space Support-Related Organization Winners o Oregon L-5 Society, Inc., Oregon City, Ore. - "Site Characterization of the Oregon Moonbase." o Tether Applications, La Jolla, Calif. - "Preliminary Design of a 1KM/SEC Tether Transport Node." Industry-Related Winners o Martin Marietta Strategic Systems, Denver, Colo. - "Study of Nuclear Thermal Rockets Utilizing Indigenous Martian Propellants." o Dean & Associates, Alexandria, Va. - "An Early Warning System for Monitoring Large Projects." o Titan Systems, Inc., San Diego, Calif. - The Evolution of Design Alternatives for the Exploration of Mars by Balloon." o Engineering Development Laboratory, Inc., Newport News, Va. - "Determination of the Concentration of Spacecraft Cabin Gases using Laser Spectroscopy." o Orbitec, Madison, Wis. - "Aluminum/Oxygen Rocket Engine for Lunar Transport Applications" and "The Use of Tethered Platforms to Recover, Store, and Utilize CO2 from the Mars Atmosphere for On- Orbit Propellants." University-Related Winners o Energy & Mineral Research Center, Grand Forks, N.D. - "Further Investigation of the Feasibility of Applying Low-Temperature Plasma Technology to a Closed-Loop Processing Resource Management System." o Texas Engineering Experiment Station, College Station, Texas - "Design of a General Purpose, Mobile, Multifunctional Radiation Shield for Space Exploration." o Boston College, Chestnut Hill, Mass. - "Design Considerations of a Lunar Production Plant." o Michigan Technological University, Houghton, Mich. - "Planetary Materials and Resource Utilization." o The Regents of the University of California, Santa Barbara, Calif. - "A Small Particle Catalytic Thermal Reactor (SPCTR) for the Conversion of CO and CO2 to Methane in a Gravity-Free Environment Vehicle." o The University of Michigan, Ann Arbor, Mich. - "Advanced Fuel Cycles for the MICF - Fusion Propulsion System." o Boston University, Boston, Mass. - "Pneumatic Structures for Lunar and Martian Habitats." o State University of New York at Stony Brook, Stony Brook, N.Y. - "Artificial Intelligence to Simulate the Green Thumb." o The Regents of the University of Colorado, Boulder, Colo. - "Mars Tethered Sample Return Study." o The University of New Mexico, Albuquerque, N.M. - "Teleprospector: A Teleoperated Robotic Field Geologist." o Duke University, Durham, N.C. - "Deployable Magnetic Radiation Shields using High Tc Superconductors: A New Concept." o International Space University, Boston, Mass. - "International Lunar Polar Orbiter (ILPO)." o The University of Texas, Houston, Texas - "Emergency Surgery and Surgical Critical Care to Support Human Exploration of the Solar System." The Office of Exploration intends to follow these selections with future solicitations for other innovative ideas and concepts. These follow-on studies could be to refine concepts studied this year or to deepen NASA's understanding or reexamine using different conditions or ground rules; or these future studies could be aimed at finding more new ideas. ------------------------------ Date: 5 Sep 89 05:49:25 GMT From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: Neptune fly-by In article <8909040021.AA08657@SIDNEY.MIT.EDU> drwho@ATHENA.MIT.EDU (Jon Monsarrat "Dr. Who") writes: >Could someone explain the reasoning behind having Voyager 2 fly off >out of the solar system? I'm not under the delusion that a course >change could be effected for it now. I was just wondering why the >scientific information gathering benefits of leaving the solar system >outweigh those of going into orbit around Neptune and shooting some >better pictures of the moons. This would have been possible with enough >"braking" around Neptune, am I wrong? Sorry, you are. Well, it would be possible with enough braking, but Voyager had no way to get that much -- it's not designed to dip into the atmosphere to brake that way, and its fuel supply is quite small. If it had been possible, it would have been done. -- V7 /bin/mail source: 554 lines.| Henry Spencer at U of Toronto Zoology 1989 X.400 specs: 2200+ pages. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ End of SPACE Digest V10 #40 *******************