Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.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 ; Sun, 20 Jan 91 02:41:11 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sun, 20 Jan 91 02:41:08 -0500 (EST) Subject: SPACE Digest V13 #065 SPACE Digest Volume 13 : Issue 65 Today's Topics: Update on CRRES releases Re: space news from Dec 17 AW&ST Magellan Update - 01/17/91 Galileo Update #2 - 01/17/91 Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: Wed, 16 Jan 1991 23:25:14 CST From: REIFF@SPACVAX.RICE.EDU (Pat Reiff (713)527-8750-2650) Subject: Update on CRRES releases X-Vmsmail-To: SMTP%"space+@andrew.cmu.edu" In response to queries on the net, here's the results from the last successful CRRES release (and the time of the next window, at 11:05 CST on 1/17). Following the first message, will be a repeat of the science objectives and a complete list of the release windows. Note that many of the windows remaining on the list will not be used because of the success of the releases so far. I'll try to find out the subset which is really remaining and post it. Does anyone have a copy of MACSAT to get altitudes and azimuths from satellite elements? If so, I can post the elements as well......Pat CRRES BOMBS THE PLASMAPAUSE!!!!! The G-4 release was performed January 16, 1991 at 06:25:00. The location of the release was right on the plasmapause boundary, as determined by simultaneous measurements with the Iowa plasma wave instrument. Howard Singer reported an initial compression of 10 gammas, followed by a diamagnetic reduction from an ambient value of 250 gammas down to 110 gammas. This reduction lasted for about 40 seconds. The CRRES on-board photometer saw the sun glint from the canister and in comparison with the particle data, the direction of the canister relative to the spacecraft was determined to be perpendicular to the magnetic field direction. The optical data were all excellent. Optical data was recorded at White Sands, Los Alamos, Millstone Hill, Long Key, St. Croix, Arecibo, Cerro Tololo, and El Leoncito. The northern and southern tips of the field-aligned ion streak were tracked for 45 minutes following the release. The next opportunity will be a high altitude lithium release on January 18 with windows beginning at 0500 UTC. David L. Reasoner January 16, 1991 CRRES JANUARY HI-ALT RELEASE CAMPAIGN The CRRES Program is on schedule for a series of high-altitude chemical releases in January, 1991. The scientific objectives of these releases may be grossly characterised as 1. Formation of Diamagnetic Cavities; 2. Cold-Plasma Seeding experiments to induce artificial precipitation; 3. Magnetospheric Injection and Ion Tracing; and 4. Plasmoid Formation. The releases will be observed with an extensive network of ground and aircraft sites. Ground sites will be located at Los Alamos, White Sands, Millstone Hill (radar and optical), Rosemary Hill, FL; and Long Key, FL in the United States. Carribean sites are St. Croix, USVI; Arecibo, P.R.; and Bonaire, Netherlands Antilles. South American sites will be located at Recife, Brazil; El Leoncito, Argentina; Cerro Tololo, Chile; and Baltra Island, Galapagos Islands, Ecuador. Three research aircraft carrying optical instruments will be used. Two USAF KC-135s will operate from K.I. Sawyer AFB near Marquette, Michigan and will fly tracks in Canada to look for artificially-induced precipitation. The Argentine/CNIE B-707 will operate from Recife, Brazil and will view the releases directly, tracing the ion motions. We expect considerable public interest as the releases will be very visible. The lithium releases will, 30 seconds following ignition, be 0.5 degree is visual diameter with an intensity at 6708 Angstroms of 1 megaRayleigh, i.e. a large and as bright as the full moon (Rev 6-12). We think someone might notice. A "Hot-Line" information number has been established at 205-544-5356. The latest release information will be available in the form of a recorded message. Attached is a table of the release windows and types. CRRES RELEASE WINDOWS FOR JANUARY, 1991 REVISED 01/05/91 BASED ON ORBIT PREDICTS EPOCH 01/04/91 ALL POSSIBLE WINDOWS ARE SHOWN. TOTAL RELEASES = 7. 3 SMALL BARIUM, 1 LARGE BARIUM, 3 LITHIUM. EACH WINDOW IS EITHER A SINGLE POINT IN TIME (SINGLE LINE) OR A SPAN (PAIRED LINES). FOR EACH WINDOW THE SATELLITE POSITIONS AT THE OPENING AND CLOSING ARE LISTED. ALL LATITUDES NORTH U.O.S. ALL LONGITUDES ARE WEST RELEASE TYPES: 1 = SMALL BARIUM 1.5 KG, 2 = LARGE BARIUM 10.8 KG, 3 = LITHIUM .74 KG ALL TIMES ARE UTC (A.K.A. GREENWICH MEAN TIME). PST = UTC-8, MST=UTC-7, CST=UTC-6, EST=UTC-5. DATE TIME LAT. LONG. ALT. REL. TYPE SUCCESS NOTES (KM) JAN 11 0143 18.1 58.5 14899 1 POSTPONED JAN 13 0218 16.8 103.5 6149 1 SUCCESSFUL! G-2 (Sm Barium) JAN 13 0258 18.0 78.1 15000 (Not done because prior was done) JAN 13 0649 8.7 85.0 33559 2,3 Done at 0705 (below) JAN 13 0844 3.2 96.2 28677 JAN 13 0705 8.0 86.7 33410 ### SUCCESSFUL! G-7 (Lg Li) JAN 15 0332 17.0 123.6 6091 1 not done JAN 15 0412 17.9 97.9 14992 JAN 15 0537 14.2 91.9 26972 1 not done JAN 15 0710 10.4 99.1 32879 ##### not done JAN 15 0806 8.1 105.1 33547 2,3 * not done JAN 15 0958 2.7 116.0 28687 JAN 16 0348 7.8 41.0 33547 2,3 * G-4 successful @ JAN 16 0539 2.5 51.8 28740 0625 UT JAN 18 0028 17.3 78.7 6137 1 won't be done JAN 18 0228 13.9 47.3 26511 JAN 18 0503 7.4 61.0 33565 2,3 * NEXT CANDIDATES JAN 18 0654 2.0 71.8 28680 DATE TIME LAT. LONG. ALTITUDE REL. TYPE (WEST) (KM) JAN 20 0142 17.4 98.7 6127 1 JAN 20 0221 17.6 73.5 14828 JAN 20 0345 13.4 67.4 26788 1 JAN 20 0454 10.4 72.1 31897 2,3 * JAN 20 0807 1.5 91.6 28724 JAN 20 0850 1.2 S 94.0 24538 1 JAN 22 0459 13.1 87.1 26790 1 JAN 22 0608 9.9 91.9 31905 2,3 * JAN 22 0922 1.0 111.4 28699 JAN 23 0552 2.5 S 47.9 23740 1 JAN 24 0915 7.1 117.1 33462 2,3 * JAN 24 1034 0.5 131.1 28748 JAN 25 0813 10.6 S 61.2 12757 1 JAN 25 0843 16.6 S 38.9 5799 * NOTES (APPLIES TO G5, G6, G7, G10 WINDOWS): 1. WINDOWS ON 1/13, 1/15, 1/16, AND 1/18 OPENED AT 1 H 25 M AFTER END OF ECLIPSE AND CLOSED WHEN GEOCENTRIC ALT. < 5.5 Re. 2. WINDOW ON 1/20 OPENED BY ALT > 6 Re AND CLOSED BY ALT < 5.5 Re. 3. WINDOWS ON 1/22 AND 1/24 OPENED BY MOONSET AT CHURCHILL AND CLOSED BY ALT < 5.5 Re. 4. ##### DENOTES PRIME G-7 (TYPE 3) RELEASE POINT. *********************************************** * RELEASE INFORMATION HOT LINE 205-544-5356 * *********************************************** ------ From the First Space Science Department in the World: : _^ ^_ ____ Patricia H. Reiff : / O O \ |GO \ Department of Space Physics and Astronomy : \ V / |OWLS\ Rice University, Houston, TX 77251-1892 : / ""R"" \__/ internet: reiff@spacvax.rice.edu (128.42.10.3) \ ""U"" / SPAN: RICE::REIFF : _/|\ /|\_ GTEtelemail: [preiff/kosmos] tm44/usa : "Why does man want to go to the Moon? ... Why does Rice play Texas?" ....JFK, Rice Stadium, 1962 ------------------------------ Date: 17 Jan 91 16:32:38 GMT From: julius.cs.uiuc.edu!wuarchive!rex!rouge!dlbres10@apple.com (Fraering Philip) Subject: Re: space news from Dec 17 AW&ST Comment regarding Broadcast CD-quality sound: With all of the bilge being broadcast over the airwaves today, what would be the point? After all, if people listened to more classical or jazz or maybe new-age music, I could see the point. But, quite simply, _Poison_ and _Nelson_ will still sound just as bad no matter how good the dynamic response is. ;-) ;-) ;-) ;-) ;-) Phil dlbres10@pc.usl.edu ------------------------------ Date: 17 Jan 91 19:26:04 GMT From: elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ames.arc.nasa.gov (Ron Baalke) Subject: Magellan Update - 01/17/91 MAGELLAN STATUS REPORT January 17, 1991 The Magellan spacecraft and its radar system continue to perform nominally after 803 mapping orbits. During the seven STARCALS (star calibrations) of the past 24 hours, one was unsuccessful due to rejects of both stars, two were partially successful with one star reject, and the remaining four were successful. One of the "successful" attitude updates accepted a false star interrupt, resulting in an incorrect attitude update of 0.09 degree. The subsequent STARCAL was successful, correcting the error. The High Gain Antenna offpoint of less than 0.09 for one orbit is within mission specs. An increase in star reference rejects has been expected as the mission geometry changes. In response to the attitude reference alarms mentioned yesterday, spacecraft controllers decided to raise the sun loss fault protection limit from 11 to 30 minutes. The fault protection keeps track of the amount of time the sensors detect a "miscompare" or abnormal measurement in "time counts" of 0.53 seconds. If the cumulative time counts reached the limit, the spacecraft would put itself into a safing mode. Although the counts remained far below the limit, controllers felt it was prudent to set the higher time limit. Again, this is believed to be a sun geometry problem which occurs periodically when one sun sensor picks up the Venus albedo, while the other views only the Sun. The weekly mapping command sequence, M1019, and its associated parameter files will be sent to the spacecraft tomorrow. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ Date: 17 Jan 91 23:37:20 GMT From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@apple.com (Ron Baalke) Subject: Galileo Update #2 - 01/17/91 GALILEO STATUS REPORT January 17, 1991 As of noon (PST) Thursday, January 17, 1991, the Galileo spacecraft is 19,464,250 miles from the Earth and traveling at a heliocentric speed of 83,560 miles per hour; distance to the Sun is 84,388,010 miles (0.90 AU). Round trip light time is 3 minutes, 26 seconds. A command was successfully sent on January 14 to reset the Command Loss Timer to 240 hours, the planned value for this mission phase. Cruise Science Memory Readouts (MROs) were successfully completed on January 14 for the EUV (Extreme Ultraviolet Spectrometer), DDS (Dust Detector) and MAG (Magnetometer) science instruments. A SITURN to lead the sun was successfully performed on January 14. The turn, about 4.8 degrees, resulted in the spacecraft leading the sun by about 2.5 degrees. Spacecraft performance during the activity was normal with no anomalies/incidents observed. A series of Delay Action Commands (DACs) were sent on January 11 to cycle the PLS (Plasma) instrument's replacement and supplemental electrical heaters off/on, respectively. This action was requested to better characterize the thermal behavior of the PLS. It was observed during the Earth 1 flyby that the PLS experienced temperatures somewhat higher than anticipated; at no time, however, was the health and safety of the instrument at risk. The PLS replacement heater was powered off and its supplemental heater activated on January 11 via DACs. DACs to reverse the heater configuration will be executed on January 18 after sufficient thermal data is collected. The CDS "B" (Commmand Data Subsystem) memory copy activity was successfully performed on January 17. This activity demonstrated the second in-flight use of the CDS copy capability. For this "B" copy activity the memory contents of CDS "B" elements (HLM1B, LLM1B, LLM2B, BUM1B) was copied from prime memory into the extended memory. Spot-check memory readouts were subsequently performed and indicated no parity errors or anomalies. This activity completes the total copy of the CDS prime memory into the extended memory and consequently reduces the time to recover from a future possible chip/location failure. Later in January a more complete CDS memory readout will be performed for both CDS "A" and "B" sides. Commands to reduce the downlink data rate from 1200 bps to 40 bps uncoded data were executed from the stored sequence on January 14. The data rate reduction is necessary until early April 1991 to ensure acceptable data quality. The data rate change occurred, as planned, and data was successfully processed by the Ground Data System (GDS) without anomaly or incident. The spacecraft reached perihelion at 0.9 AU on January 11; thermal profiles were near expected levels and no anomalies/incidents were observed. From this point on, the spacecraft will recede from the sun as it travels toward an encounter with asteroid Gaspra (about 2.1 AU) in late October 1991 prior to its planned second Earth flyby in December 1992. Due to the lack of valid star sets and required attitude constraints between January 16 and February 25, the spacecraft's operating mode was changed from the dual-spin mode to the all-spin mode. In the all-spin mode, the spacecraft will be commanded via the stored sequence to perform sun acquisitions about every two days to maintain the tight sun point attitude constraint necessary for thermal safety. The spacecraft has operated previously in the all-spin mode for extended time periods without anomaly or incident. The first time was between launch and the first dual-spin transition (about L + 15 days), and the other about 20 days in response to spacecraft safing execution in January 90. In spacecraft safing, unlike those commanded from sequence, sun acquisitions were performed automatically every 12 hours from the sun point fault protection algorithm. The AC/DC bus imbalance measurements exhibited some activity. The AC measurement increased about 2 DN and now reads 46.6 volts. The DC bus measurement increased about 4 DN and now reads 13.9 volts. No significant changes were observed in either measurements when going from dual-spin to all-spin operation. All other power-related measurements and spacecraft telemetry are normal. The GDS test program for the German Space Operations Center (GSOC) Cruise Science operations support in September has started. GSOC internal testing of their telemetry system has been in process since early January. Command System testing is scheduled to start next week. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ End of SPACE Digest V13 #065 *******************