STEREO Weekly Meeting Minutes for 2012-04-24 (Week 17) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 16 (Apr 16-22) * On day 108 (Apr 17), during the DSS-15 support for Ahead, AOS was delayed 2.7 hours due to loss of electrical power to the station. After power was restored, telemetry lock was established at 1531z. The planned momentum dump for this support was moved to DOY 109, with ignition at 1600z, as there was insufficient time to conduct it. SSR pointers were reset to minimize science data loss. This anomaly resulted in the loss 2.7 hours of commanding, tracking, and real-time telemetry data and the SSR data loss listed below. See DR# G112589 for more information. IMPACT reached 95% full: 0.3 hours beginning at 109-1321z 1.0 hours beginning at 112-1136z 5.9 hours beginning at 113-0727z SWAVES reached 100% full: 1.5 hours beginning at 109-1205z 4.8 hours beginning at 112-0032z 0.1 hours beginning at 112-0526z 2.1 hours beginning at 112-1031z 9.1 hours beginning at 113-0415z * SWAVES reports that, although they saw some data losses, it wasn't as bad as reported above. * On day 110 (Apr 19), for the DSS-15 support for Ahead, telemetry lock was lost beginning at 1821z due to the antenna brakes being set inadvertently. The brakes were reset and telemetry lock was re-established at 1831z. This anomaly resulted in the loss of 46 minutes of SSR data for each instrument. See DR# G112598 for more information. * On day 111 (Apr 20), during the DSS-63 support for Ahead, turbo decoder lock was lost intermittently beginning at 0811z through 0823z. This anomaly resulted in the loss of 75 frames of SSR data. See DR# N108041 for more information. * On day 113 (Apr 22), during the DSS-34 support for Ahead, turbo decoder lock was lost briefly at 2303z. This anomaly resulted in the loss of one frame of SSR data. See DR# N108044 for more information. * On day 107 (Apr 16), a flight software patch was loaded to the IMPACT LET instrument on Ahead to correct an error in the total-energy calculation. The same patch was loaded on Behind on day 109 (Apr 18). * On day 109 (Apr 18), the 46th momentum dump on Ahead was successfully executed at 1600Z, which imparted a delta V of 0.1011 m/sec. * On day 112 (Apr 21), during the DSS-15 support for Behind, turbo decoder lock was lost intermittently beginning at 0338z. This anomaly resulted in the loss of 167 frames of SSR data. See DR# N108045 for more information. * On day 112 (Apr 21), during the DSS-55 support for Behind, turbo decoder lock was lost briefly at 1832z. This anomaly resulted in the loss of one frame of SSR data. See DR# N108046 for more information. * On day 113 (Apr 22), during the DSS-65 support for Behind, turbo decoder lock was lost briefly beginning at 1210z and again at 1347z. This anomaly resulted in the loss of 64 frames of SSR data. See DR# N108047 for more information. * On day 113 (Apr 22), during the DSS-14 support for Behind, AOS was delayed 2 minutes due to telemetry receiver anomaly at the station. After another downlink channel was added, telemetry lock was established at 1902z. This anomaly resulted in the loss 2 minutes of real-time telemetry data and the SSR data were recovered. See DR# G112609 for more information. * The average daily SSR playback volume during the week was 4.2 gigabits for Ahead, and 4.6 gigabits for Behind. Week 17 (Apr 23-29) * Turbo lock was lost momentarily at 7:10 UT during the station 55 pass for Ahead yesterday (Apr 23). * Turbo lock was lost momentarily during the station 63 pass for Behind yesterday (Apr 23). * There was a 2.75 hour return-to-service track for station 26 on Ahead yesterday (Apr 23). The signal looked good. * Ahead has 70 meter tracks on Monday, Apr 23 (D14), Tuesday, Apr 24 (D14, D43), Wednesday, Apr 25 (D63), Thursday, Apr 26 (D63 at 720 kbps), Friday, Apr 27 (D63), Saturday, Apr 28 (D63), and Sunday, Apr 29 (D63). There are 10 tracks during the week, and overall coverage is nominal. * Behind has 70 meter tracks on Monday, Apr 23 (D63), Tuesday, Apr 24 (D14 at 720 kbps), Wednesday, Apr 25 (D14 at 720 kbsp), Thursday, Apr 26 (D14 at 720 kbps), Friday, Apr 27 (D63 at 720 kbps), Saturday, Apr 28 (D14), and Sunday, Apr 29 (D63 at 720 kbps). There are 8 passes during the week, and overall coverage is nominal. Week 18 (Apr 30-May 6) * The ability to downlink from Ahead with 34 meter stations through the low-gain antenna will end on Monday, Apr 30. The same happened on Behind last fall. * A test of the Data Capture and Delivery System (DCDS) will take place on Wednesday, May 2, starting at 14:00 UT for 1 hour. Old Behind data from day 101 (Apr 10) will be flowing during this test. However, these data should not be seen by the instrument teams. * Ahead has 70 meter tracks on Monday, Apr 30 (D14 at 720 kbps), Thursday, May 3 (D14), and Saturday, May 5 (D63 at 720 kbps). There are 11 passes during the week, and the overall coverage is nominal. The station 15 pass on Tuesday, May 1, will be carried out at 240 kbps. An ESA Cebreros pass is scheduled for Friday, May 4. * Behind has 70 meter passes on Tuesday, May 1 (D63 at 720), Wednesday, May 2 (D63, D14 at 720 kbps), Thursday, May 3 (D63), and Saturday, May 5 (D63 at 720 kbps). There are 10 passes during the week, and overall coverage is nominal. The station 55 pass on Monday, Apr 30, the station 54 pass on Friday, May 4, and the station 65 pass on Sunday, May 6, will all be carried out at 240 kbps. Passes with the ESA New Norcia station are scheduled for Monday, Apr 30, and Friday, May 4. Week 19 (May 7-13) * Ahead has 70 meter passes on Monday, May 7 (D63 and D14), Wednesday, May 9 (D63), Thursday, May 10 (D63), Friday, May 11 (D14 at 720 kbps), and Sunday, May 13 (D14 at 720 kbps). There are 11 passes during the week, and overall coverage is nominal. The station 54 pass on Tuesday, May 8, and the station 25 pass on Thursday, May 10 will be carried out at 240 kbps. * Behind has 70 meter passes on Monday, May 7 (D63 at 720 kbps), Tuesday, May 8 (D63 at 720 kbps), Thursday, May 10 (D14), and Friday, May 11 (D63). There are 9 passes during the week, and overall coverage is nominal. The station 55 pass on Wednesday, May 9, the station 55 and 15 passes on Saturday, May 12, and the station 55 pass on Sunday, May 13, will all be carried out at 240 kbps. Week 20 (May 14-20) * The 41st momentum dump on Behind is scheduled for Tuesday, May 15, with ignition at 17:00 UT. The next momentum dump for Ahead has not been scheduled yet. * Ahead has 70 meter passes on Wednesday, May 16 (D14 at 720 kbps), Thursday, May 17 (D14 at 720 kbps), Friday, May 18 (D63), Saturday, May 19 (D14, D43), and Sunday, May 20 (D63). There are 11 passes during the week, and overall coverage is nominal. The station 15 pass on Monday, May 14, the station 25 pass on Tuesday, May 15, the station 55 pass on Saturday, May 19, and the station 25 pass on Sunday, May 20, will all be carried out at 240 kbps. * Behind has 70 meter passes on Monday, May 14 (D43), Wednesday, May 16 (D63), Thursday, May 17 (D63), Friday, May 18 (D14 at 720 kbps), Saturday, May 19 (D14 at 720 kbps), and Sunday, May 20 (D63 at 720 kbsp). There are 8 passes during the week, and overall coverage is nominal. The station 65 pass on Monday, May 14 will be carried out at 240 kbps. Week 21 (May 21-27) * There is a 3 hour return-to-service track for station 65 with Behind on Friday, May 25, starting at 17:00 UT. There will be no SSR playback nor instrument commanding during this track. * Perihelion for Behind will occur on May 22. However, system momentum will be high, and the calibration roll will be scheduled for the following week. * Ahead has 70 meter passes on Monday, May 21 (D14), Tuesday, May 22 (D14 at 720 kbps), Wednesday, May 23 (D14, D43), Thursday, May 24 (D63), Friday, May 25 (D63, D14 at 720 kbps), and Saturday, May 26 (D63, D43 at 720 kbps). There are 12 passes during the week, and overage coverage is nominal. * Behind has 70 meter passes on Monday, May 21 (D63 at 720 kbps), Tuesday, May 22 (D63 at 720 kbps), Wednesday, May 23 (D14 at 720 kbps), Thursday, May 24 (D63), Friday, May 25 (D63), and Saturday, May 26 (D63 at 720 kbps). COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 17: M Apr 23 (114) Ahead: Return-to-service track for station 26. T Apr 24 (115) W Apr 25 (116) T Apr 26 (117) F Apr 27 (118) S Apr 28 (119) S Apr 29 (120) Note: * SCOSTEP Observing and Modeling Campaign On Space Weather Events (SOMCOSE), March 29 - April 30, tracking return of NOAA 11429. http://solar.physics.montana.edu/hypermail/mmscience/0856.html ------------------------------------------------------------------------------- Scheduled activities for Week 18: M Apr 30 (121) Ahead: End downlink with LGA on 34 meter stations T May 01 (122) W May 02 (123) Behind: DCDS test, 14-15 UT T May 03 (124) F May 04 (125) S May 05 (126) S May 06 (127) Note: * SCOSTEP Observing and Modeling Campaign On Space Weather Events (SOMCOSE), March 29 - April 30, tracking return of NOAA 11429. http://solar.physics.montana.edu/hypermail/mmscience/0856.html * Old data will be flowing during the DCDS test. ------------------------------------------------------------------------------- Scheduled activities for Week 19: M May 07 (128) T May 08 (129) W May 09 (130) T May 10 (131) F May 11 (132) S May 12 (133) S May 13 (134) ------------------------------------------------------------------------------- Scheduled activities for Week 20: M May 14 (135) T May 15 (136) Behind: Momentum dump, 17:00 UT W May 16 (137) T May 17 (138) F May 18 (139) S May 19 (140) S May 20 (141) ------------------------------------------------------------------------------- Scheduled activities for Week 21: M May 21 (142) T May 22 (143) Behind: Perihelion W May 23 (144) T May 24 (145) F May 25 (146) Behind: Return-to-service track with station 65 S May 26 (147) S May 27 (148) ------------------------------------------------------------------------------- Upcoming events: 2012: * Jul DAWN - Vesta departure * Jul 11 Both: HGA calibration * Nov 4 Behind: Switch downlink rate to 120 kbps * Nov 13 Total solar eclipse, south Pacific 2013: * May 3 Ahead: Switch downlink rate to 120 kbps * Dec 12 Ahead: Mercury transit 2014: * Jan 20 Behind: End use of 480 kbps on 70 m DSN subnet * Apr 21 Behind: Resume use of 480 kbps on 70 m DSN subnet * Apr 29 Behind: Mercury transit * Oct 15 Behind: End use of 480 kbps on 70 m DSN subnet 2015: * Feb DAWN - Ceres arrival * Jan 20 - Mar 28 (TBC) Behind: Spacecraft behind Sun * Mar 17 - Jul 14 (TBC) Ahead: Spacecraft behind Sun * Jul 2 Behind: Resume use of 480 kbps on 70 m DSN subnet * Aug 25 - Oct 19 (TBC) Behind: Spacecraft behind Sun * Sep 25 Behind: End use of 480 kbps on 70 m DSN subnet * Jul DAWN - End of nominal mission 2016: * Apr 3 Behind: Resume use of 480 kbps on 70 m DSN subnet 2017: * Jul 11 Ahead: Switch downlink rate to 160 kbps * Jul 22 Behind: Switch downlink rate to 160 kbps 2018: * Mar 5 Ahead: Mercury transit