STEREO Weekly Meeting Minutes for 2012-06-26 (Week 26) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 25 (Jun 18-24) * On day 170 (Jun 18), during the DSS-65 support for Ahead, turbo decoder lock was lost intermittently from 0619z through 0624z. This anomaly resulted in the loss of 17 frames of SSR data. See DR# N108179 for more information. * On day 171 (Jun 19), during the DSS-26 support for Ahead, the antenna could not be pointed as the antenna brake could not be released for the entire 3 hour track (1145-1445z). The SSR pointers were repositioned and all SSR data were received. See DR# G112874 for more information. * On day 172 (Jun 20), during the DSS-65 support for Ahead, monitor data was lost from 0513z to 0515z due to a reset of the router at the Madrid complex. All SSR data were received. See DR# N108180 for more information. * On day 174 (Jun 22), during the DSS-63 support for Ahead, turbo decoder lock was lost intermittently at 0514z. This anomaly resulted in the loss of three frames of SSR data. See DR# N108191 for more information. * On day 174 (Jun 22), during the DSS-43 support for Ahead, the primary DCD was inadvertently powered down at 2109z. It was powered on and placed on-line again at 2113z. All SSR data were subsequently recovered. See DR# N108194 for more information. New telemetry files (version 04) were generated last night (Jun 25). * On day 176 (Jun 24), during the DSS-24 support for Ahead, the primary telemetry processor did not lock to the downlink at BOT at 1140z. A backup telemetry processor was placed on-line and telemetry lock occurred at 1146z. At 1226z, the turbo decoder lost lock briefly. At 1514z, the uplink was lost when the transmitter tripped off-line. The support remained downlink only for the 2.3 hour remainder. These anomalies resulted in the loss of 136 minutes of commanding and two-way tracking data and 274 frames of SSR data. See DR# G112890 and G112891 for more information. * On day 172 (Jun 20), the Flight Dynamics Facility notified the DSN that no tracking data had been received by FDF for the Behind spacecraft since DOY 169 (Jun 17). The interruption was caused by a stale TDS query to the FDF. This process was terminated and restarted. All tracking data were recovered. See DR# N108183 for more information. * On day 172 (Jun 20), during the DSS-65 support for Behind, turbo decoder lock was lost intermittently from 1801z through 1920z. This anomaly resulted in the loss of 77 frames of SSR data. See DR# N108184 for more information. * On day 173 (Jun 21), during the DSS-65 support for Behind, turbo decoder lock was lost intermittently at 0831z, 0832z, and again at 0918z. This anomaly resulted in the loss of 38 frames of SSR data. See DR# N108185 for more information. * On day 174 (Jun 22), during the DSS-34 support for Behind, turbo decoder lock was lost intermittently at 0658z. This anomaly resulted in the loss of one frame of SSR data. See DR# N108189 for more information. * On day 174 (Jun 22), during the DSS-55 support, turbo decoder lock was lost intermittently at 1358z. This anomaly resulted in the loss of three frames of SSR data. See DR# N108190 for more information. * The average daily SSR playback volume during the week was 4.6 gigabits for Ahead, and 4.9 gigabits for Behind. * The DSN is actively looking into the turbo decoder lock problem. Signs are promising that this problem will be fixed soon. Week 26 (Jun 25-Jul 1) * Ahead's 22nd SECCHI step calibration roll took place this morning (Jun 26). * Turbo decoder lock was lost briefly during the station 63 pass for Ahead yesterday (Jun 25), resulting in the loss of a few frames of data. * A leap second will be added on both spacecraft on Sunday, Jun 30 at 23:59:59 UT to keep them coordinated with UTC. Instruments will see this in their DPU. The difference between TAI and UTC will go from 34 to 35 seconds. * A test track with Behind occurred today (Jun 26) for station 25, shadowing the station 24 track. * There will be a return-to-service track for station 25 on Behind on Sunday, Jul 1, for 3 hours starting at 16:55 UT. There will be no SSR playback nor instrument commanding during this track. * Ahead has 70 meter passes on Monday, Jun 25 (D63, D14), Tuesday, Jun 26 (D63 at 720 kbps, D14), Wednesday, Jun 27 (D63), Thursday, Jun 28 (D43 at 720 kbps, D14). The 70 meter pass on Saturday has been cancelled. The D55 passes on Saturday, Jun 30 and Sunday, Jul 1 will both be at 240 kbps. There will be 11 tracks total during the week and overall coverage will be nominal. * Behind has 70 meter passes on Monday, Jun 25 (D63), Friday, Jun 29 (D63), Saturday, Jun 30 (D14) and Sunday, Jul 1 (D63) all at 480 kbps. Passes on Tuesday, Jun 26 on D24 and Wednesday, Jun 27 on D65 will be at 240 kbps. There are 13 tracks total during the week, and overall coverage is nominal. The previous telemetry shortage on Thursday, Jun 28 was alleviated by the addition of ESA New Norcia and Cebreros passes that day. Week 27 (Jul 2-8) * Wednesday, Jul 4 is an APL Holiday, so please coordinate real time support in advance. * Ahead has 70 meter tracks on Tuesday, Jul 3 (D14), Wednesday, Jul 4 (D14), Friday, Jul 6 (D43), and Saturday, Jul 7 (D63). The D65 track on Sunday, Jun 8 will be carried out at 240 kbps. There will be a total of 11 tracks during the week, and coverage will be nominal. * Behind has 70 meter tracks on Monday, Jul 2 (D63), Tuesday, Jul 3 (D63 at 720 kbps), Wednesday, Jul 4 (D14 at 720 kbps), Thursday, Jul 5 (D43), and Friday, Jul 6 (D14 at 720 kbps). The D24 track on Saturday, and D54 track on Sunday, will be at 240 kbps. There will be 11 tracks total during the week, and overall coverage will be nominal. Week 28 (Jul 9-15) * 70 meter station 63 will be down during weeks 28-29, causing shortages in the schedule during these weeks. Contingency plans are in place for weeks 30-31 in case station 63 is still down. * The 16th HGA calibrations are scheduled for Ahead on Thursday, Jul 12, starting at 13:30 UT, and for Behind on Wednesday, Jul 11, starting at 15:00 UT. Each is an 11 hour support. * The 48th momentum dump on Ahead is scheduled for Friday, Jul 13, starting at 16:30 UT. * Ahead has 70 meter tracks on Monday, Jul 9 (D14), Wednesday, Jul 11 (D14 at 720 kbps), Friday, Jul 13 (D14 at 720 kbps), and Sunday, Jul 15 (D14). There are 13 passes during the week, and overall coverage is nominal. The station 15 pass on Sunday, Jul 15 will be carried out at 240 kbps. ESA New Norcia passes are scheduled for Saturday, Jul 14, and Sunday, Jul 15. * Behind has 70 meter tracks on Wednesday, Jul 11 (D14), and Saturday, Jul 14 (D14 at 720 kbps). The station 34 pass on Tuesday, July 10, and the station 24 pass on Friday, Jul 13 will both be carried out at 240 kbps. ESA New Norcia station passes are scheduled for Monday, Jul 9, and Sunday, Jul 15, and an ESA Cebreros pass is scheduled for Sunday, Jul 15. Coverage is short 6.5 hours between Monday and Tuesday, Jul 9-10, and 8.5 hours short on Sunday, Jul 15 and the following Monday. Week 29 (Jul 16-22) * The 43rd momentum dump on Behind is scheduled for Tuesday, Jul 17, starting at 19:30 UT. * Ahead has 70 meter tracks on Thursday, Jul 19 (D14), and Friday, Jul 20 (D43). There are 15 tracks during the week, and overall coverage is nominal. The station 15 track on Saturday, Jul 21 will be carried out at 240 kbps. ESA New Norcia passes are scheduled for Monday, Jul 16, Tuesday, Jul 17, Wednesday, Jul 18, and Saturday, Jul 21, and an ESA Cebreros pass is scheduled for Tuesday, Jun 17. * Behind has 70 meter tracks on Tuesday, Jul 17 (D14), Wednesday, Jul 18 (D14 at 720 kbps), Friday, Jul 20 (D14), Saturday, Jul 21 (D14), and Sunday, Jul 22 (D14). There are 14 passes during the week, and overall coverage is short 8.5 hours between days 197-198 (Jul 15-16), and 2-3 hours on Saturday, Jul 21. The station 55 pass on Thursday, Jul 19 will be carried out at 240 kbps. ESA Cebreros passes are scheduled for Monday, Jul 16 (1 hour), Thursday, Jul 19, and Sunday, Jul 22, and ESA New Norcia passes are scheduled for Wednesday, Jul 18, Thursday, Jul 19, Friday, Jul 20, and Sunday, Jul 22. The in situ instruments may be able to mostly ride through these data shortages in weeks 28-29, but SECCHI will definitly need to cut back on their observing schedule. Week 30 (Jul 23-29) * Ahead has 70 meter tracks on Monday, Jul 23 (D14), Tuesday, Jul 24 (D14), Wednesday, Jul 25 (D14), Thursday, Jul 26 (D14), Friday, Jul 27 (D63), and Sunday, Jul 29 (D63). There are 12 tracks during the week, and overall coverage is nominal. * Behind has 70 meter tracks on Monday, Jul 23, Tuesday, Jul 24, and Saturday, Jul 28, all using station 14. The station 24 track on Thursday, Jul 26 will be carried out at 240 kbps. ESA New Norcia passes are scheduled for Friday and Saturday, Jul 27-28. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 26: M Jun 25 (177) T Jun 26 (178) Ahead: SECCHI stepped calibration roll, 2:20 UT W Jun 27 (179) T Jun 28 (180) F Jun 29 (181) S Jun 30 (182) Both: Leap second added at 23:59:59 UT S Jul 01 (183) Behind: Return-to-service track for station 25 ------------------------------------------------------------------------------- Scheduled activities for Week 27: M Jul 02 (184) T Jul 03 (185) W Jul 04 (186) Independence Day T Jul 05 (187) F Jul 06 (188) S Jul 07 (189) S Jul 08 (190) ------------------------------------------------------------------------------- Scheduled activities for Week 28: M Jul 09 (191) T Jul 10 (192) W Jul 11 (193) Behind: HGA calibration, 13:30 UT T Jul 12 (194) Ahead: HGA calibration, 15:00 UT F Jul 13 (195) Ahead: Momentum dump, 16:30 UT S Jul 14 (196) S Jul 15 (197) ------------------------------------------------------------------------------- Scheduled activities for Week 29: M Jul 16 (198) T Jul 17 (199) Behind: Momentum dump, 19:30 UT W Jul 18 (200) T Jul 19 (201) F Jul 20 (202) S Jul 21 (203) S Jul 22 (204) ------------------------------------------------------------------------------- Scheduled activities for Week 30: M Jul 23 (205) T Jul 24 (206) W Jul 25 (207) T Jul 26 (208) F Jul 27 (209) S Jul 28 (210) S Jul 29 (211) ------------------------------------------------------------------------------- Upcoming events: 2012: * Aug DAWN - Vesta departure * 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