STEREO Weekly Meeting Minutes for 2014-05-27 (Week 22) ANNOUNCEMENTS ------------- * An agreement is in place with ESA to provide 380 hours of support between now through 2016. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 21 (May 19-25) * On day 141 (May 21), during the DSS-55 support for Ahead, turbo decoder lock was lost intermittently beginning at 0741z through 1104z due to rain. This anomaly resulted in the loss of 437 frames of SSR data. See DR #M107998 more information. * On day 143 (May 23), during the DSS-14 support for Ahead, telemetry was lost from 1829z through 1831z due to the antenna brakes being applied. This anomaly resulted in the loss 8244 frames of SSR data. See DR #G115060 for more information. * On day 144 (May 24), during the DSS-65 support for Ahead, turbo decoder lock was lost intermittently beginning at 0650z through 0705z. This anomaly resulted in the loss of nine frames of SSR data. * On day 145 (May 25), during the DSS-55 support for Ahead, turbo decoder lock was lost briefly at 0622z. This anomaly resulted in the loss of six frames of SSR data. * On day 140 (May 20), the 30th SECCHI stepped calibration for the midpoint in the orbit was executed successfully on Ahead at 1445z. * On day 139 (May 19), during the DSS-63 support for Behind, turbo decoder lock was lost briefly at 1211z. This anomaly resulted in the loss of 21 frames of SSR data. * On day 142 (May 22), during the DSS-54 support for Behind, turbo decoder lock was lost briefly at 1152z. Also, the transmitter failed at 1355z, but had no impact on operations since all command activity was complete. The turbo decoder anomaly resulted in the loss of six frames of SSR data. See DR #M107999 for more information on transmitter failure. * On day 144 (May 24), during the DSS-55 support for Behind, turbo decoder lock was lost briefly at 0807z. This anomaly resulted in the loss of two frames of SSR data. * On day 140 (May 20), PLASTIC conducted real-time commanding on Behind at 1625z to adjust the MCP voltage. * The average daily SSR playback volume during the week was 5.1 gigabits on Ahead, and 5.5 gigabits on Behind. Week 22 (May 26-Jun 1) * On Wednesday, May 28, parameters will be loaded to EEPROM on the Ahead spacecraft in preparation for conjunction. * Ahead has 12 passes during the week, and overall coverage is nominal. 70 meter passes, all at 720 kbps, are scheduled for Monday, May 26 (D14), Friday, May 30 (D63), and Saturday, May 31 (D63). The following passes will be carried out at 160 kbps: Tuesday, May 27 (D55), Friday, May 30 (D26), and Sunday, Jun 1 (D25). The station 26 pass on Wednesday, May 28, will be carried out at 240 kbps. * Behind has 8 passes during the week, and overall coverage is nominal. 70 meter passes, all at 720 kbps, are scheduled for Monday, May 26 (D63), Tuesday, May 27 (D14), and Saturday, May 31 (D14). The following station 55 passes will be carried out at 160 kbps: Wednesday, May 28, Thursday, May 29, and Friday, May 30. The station 26 pass on Sunday, Jun 1, will be carried out at 240 kbps. Week 23 (Jun 2-8) * Momentum dumps are scheduled for both spacecraft on Tuesday, Jun 3. The 68th dump on Ahead is scheduled to start at 17:30 UT, and the 63rd dump on Behind is scheduled for 23:00 UT. * On Saturday, Jun 7, there will tentatively be an LGA calibration test on Ahead using D14. The scripts are still being tested. This will involve rolling the spacecraft about the Sun line at a rate of 5 degrees per minute. There will be two rolls, each of 72 minutes duration. There may also be a test of the HGA side lobe after the LGA test. A detailed schedule will be available by the end of the week. * Ahead has 12 passes during the week, and overall coverage is nominal. 70 meter passes, all at 720 kbps, are scheduled for Monday, Jun 2 (D63), Thursday, Jun 5 (D14), Friday, Jun 6 (D14), Saturday, Jun 7 (D14), and Sunday, Jun 8 (D63). The station 45 pass on Thursday, Jun 5, will be carried out at 160 kbps. The following station 26 passes will be carried out at 240 kbps: Monday, Jun 2, and Sunday, Jun 8. * Behind has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Wednesday, Jun 4 (D63 at 720 kbsp), and Friday, Jun 6 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Monday, Jun 2 (D25), Tuesday, Jun 3 (D15), Friday, Jun 6 (D55), Saturday, Jun 7 (D55), and Sunday, Jun 8 (D55). The station 26 pass on Saturday, Jun 7, will be carried out at 240 kbps. Week 24 (Jun 9-15) * On Tuesday, Jun 10, and Thursday, Jun 12, there will be downloads of MOps macros and fault protection releases to EEPROM on both spacecraft in preparation for solar conjunction. Date and time tentative. * Ahead has 13 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jun 9 (D14 at 720 kbps), Friday, Jun 13 (D63), and Saturday, Jun 14 (D63 at 720 kbps). The following passes will be carried out at 160 kbps: Tuesday, Jun 10 (D24), Thursday, Jun 12 (D26), Friday, Jun 13 (D26), and Saturday, Jun 14 (D25). The following station 26 passes will be carried out at 240 kbps: Thursday, Jun 12, and Sunday, Jun 15. * Behind has 10 passes during the week, and overall coverage is nominal. 70 meter passes, both at 720 kbps, are scheduled for Monday, Jun 9 (D63), and Wednesday, Jun 11 (D14). The following passes will be carried out at 160 kbps: Tuesday, Jun 10 (D55), Thursday, Jun 12 (D55), Friday, Jun 13 (D55), Saturday, Jun 14 (D54), and Sunday, Jun 15 (D25). Week 25 (Jun 16-22) * Mission operations spacecraft testing readiness review Thursday June 19 for Ahead * Ahead has 10 passes during the week, and overall coverage is nominal. A 70 meter pass with station 43 at 720 kbps is scheduled for Saturday, Jun 21. The following passes will be carried out at 160 kbps: Thursday, Jun 19 (D55), Friday, Jun 20 (D65), and Saturday, Jun 21 (D65). The following station 26 passes will be carried out at 240 kbps: Wednesday, Jun 18, and Sunday, Jun 22. * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jun 16 (D63), Friday, Jun 20 (D63 at 720 kbps), and Sunday, Jun 22 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Monday, Jun 16 (D65), Tuesday, Jun 17 (D55), Wednesday, Jun 18 (D55), Thursday, Jun 19 (D54), and Saturday, Jun 21 (D25). Week 26 (Jun 23-29) * Ahead has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Thursday, Jun 26 (D43), Friday, Jun 27 (D63, D14 at 720 kbps), and Saturday, Jun 28 (D63 at 720 kbsp). The following passes will be carried out at 160 kbps: Saturday, Jun 28 (D25), and Sunday, Jun 29 (D65). * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jun 23 (D14 at 720 kbsp), Tuesday, Jun 24 (D43 at 720 kbps), and Wednesday, Jun 25 (D63). The following passes will be carriedd out at 160 kbps: Tuesday, Jun 24 (D55), Thursday, Jun 26 (D65), Friday, Jun 27 (D55), and Saturday, Jun 28 (D55). The station 26 pass on Saturday, Jun 28, will be carried out at 240 kbps. Other * There was some discussion about the possibility of operating the instruments during the period when the HGA side lobes are being used. There are still some questions which need to be resolved, so nothing is finalized yet. The current thinking is that a telemetry rate of 1-10 kbps may be achievable, depending on various factors such as which side lobe is being used. This is not enough telemetry to bring down all the spacecraft housekeeping. A new mode of operations needs to be developed. Some of the possibilities which were discussed are as follows: - The SSR partitions will be reallocated to be devoted to spacecraft housekeeping data. No space will be available for instruments, which means that no instrument playback will be possible. Since repartitioning the SSR losses all data on the recorder, this can only be done once. - The first priority will be to bring down housekeeping data to ensure that the spacecraft is healthy, and to upload and verify commands. It may be possible to bring down about an hour of instrument data at the beacon rate of 630 bps. Currently, no download of instrument housekeeping is envisioned. - Instruments would be shut down for the reconfiguration of the spacecraft at the start of conjunction operations. Once the spacecraft is in a stable configuration, the instruments can be brought back up. It was expressed that instruments would need access to their housekeeping during power on. * IMPACT stated that if they didn't have access to their housekeeping packets, they would have to remain off. This would also mean that PLASTIC would be off. * SWAVES felt that they could continue operating with only space weather beacon data, but would prefer to have some housekeeping data, even if it was only for one hour per day. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 22: M May 26 (146) Memorial Day T May 27 (147) W May 28 (148) T May 29 (149) F May 30 (150) S May 31 (151) S Jun 01 (152) ------------------------------------------------------------------------------- Scheduled activities for Week 23: M Jun 02 (153) T Jun 03 (154) Momentum dumps, Ahead: 17:30 UT, Behind: 23:00 UT W Jun 04 (155) T Jun 05 (156) F Jun 06 (157) S Jun 07 (158) Ahead: LGA calibration test (TBC) S Jun 08 (159) ------------------------------------------------------------------------------- Scheduled activities for Week 24: M Jun 09 (160) T Jun 10 (161) W Jun 11 (162) T Jun 12 (163) F Jun 13 (164) S Jun 14 (165) S Jun 15 (166) ------------------------------------------------------------------------------- Scheduled activities for Week 25: M Jun 16 (167) T Jun 17 (168) W Jun 18 (169) T Jun 19 (170) F Jun 20 (171) S Jun 21 (172) S Jun 22 (173) ------------------------------------------------------------------------------- Scheduled activities for Week 26: M Jun 23 (174) T Jun 24 (175) W Jun 25 (176) T Jun 26 (177) F Jun 27 (178) S Jun 28 (179) S Jun 29 (180) ------------------------------------------------------------------------------- Upcoming events: 2014: * Sep 07-Nov 15 Behind: Passage of Comet Siding Spring through HI2-B * Sep 21 MAVEN arrival at Mars * Oct 17 Behind: Comet Siding Spring encounter with Mars 2015: * Jan 14 - Mar 19 (TBC) Behind: Spacecraft behind Sun * Mar DAWN - Ceres arrival * Feb 11 - Jul 08 (TBC) Ahead: Spacecraft behind Sun * Aug 25 - Oct 19 (TBC) Behind: Possible interference from Sun * Jul DAWN - End of nominal mission 2016: * Jul 5 Juno arrival at Jupiter 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