STEREO Weekly Meeting Minutes for 2011-11-15 (Week 46) ANNOUNCEMENTS ------------- * None INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 45 (Nov 7-13) * On day 315 (Nov 11), during the DSS 63 support for Ahead, turbo decoder lock was lost briefly beginning at 0807z. This anomaly resulted in the loss of three frames of SSR data. See DR# N107734 for more information. * On day 317 (Nov 13), for the DSS 14 support for Ahead, telemetry lock was lost beginning at 1659z due to the antenna brakes being set. The antenna controller was reset and telemetry lock was reestablished at 1727z. This anomaly resulted in the loss of three to five hours of SSR data for each instrument. See DR# G112113 for more information. Communication was established right at the end of the track so that pointers could not be repositioned, and it was a 720 kbps pass, thus leading to significant data loss. * On day 311 (Nov 7), a battery conditioning event was successfully conducted on the AHEAD S/C to redistribute the electrolytes within the nickel hydrogen battery cells. The same procedure will be performed on Behind on Dec 8. * On day 314 (Nov 10), during the DSS 63 support for Behind, turbo decoder lock was lost briefly beginning at 1605z and again at 1633z. This anomaly resulted in the loss of 137 frames of SSR data. See DR# N107737 for more information. * On day 312 (Nov 8), MOps permanent macro release 1.1.13 was loaded to C&DH RAM on Behind. This release added an autonomy rule to protect the main bus voltage during the annual battery conditioning event. * On day 312 (Nov 8), the 19th SECCHI stepped calibration, for aphelion, was executed on Behind. * On day 313 (Nov 9), STEREO BEHIND was at aphelion in its heliocentric orbit. * The average daily SSR playback volume was 4.8 gigabits for Ahead, and 4.3 gigabits for Behind. Week 46 (Nov 14-20) * The 42nd momentum dump on Ahead occurred today (Nov 15), and went well. * The 36th momentum dump on Behind is scheduled for tomorrow (Nov 16), with ignition at 22:00 UT. * Telemetry lock was lost yesterday during the Behind track on station 55 at 15:30 UT due to heavy rain. Lock was lost two times. Pointers were repositioned. * A Downlink Signal Generator (DSG) data flow test with DSS 15 at Goldstone will be held on Nov. 16 14:15-16:15 UT to test out new equipment. Instrument teams will see old (pre-launch) data flowing during this time. * Ahead has 70 meter passes on Monday, Nov 14 (D14), Tuesday, Nov 15 (D14), Friday, Nov 18 (D63), and Saturday, Nov 19 (D63). All but the Monday pass will be carried out at 720 kbps. There are 10 passes during the week, and overall coverage is nominal. * Behind has 70 meter passes on Tuesday, Nov 15 (D14), Wednesday, Nov 16 (D14), and Thursday, Nov 17 (D43). There are 11 passes during the week, and overall coverage is nominal. Week 47 (Nov 21-27) * Thanksgiving is on Thursday, Nov 24. The following Friday is also a holiday at APL. * The launch window for the MSL (Curiosity) mission opens at 15:21 UT on Nov 25. Launch contingency DSN schedules are now available covering a week after Nov 25. There would be no changes in the Behind schedule. There is a potential for data loss on Ahead, but overall the changes are not bad. The contingency schedules show up in the weekly schedules, with remarks. * There is a TEDRIS emergency in effect. It has affected the DSN schedules for SOHO, but not for STEREO so far. * Ahead has a 70 meter pass on Wednesday, Nov 23 using station 14. There are 12 passes during the week, and overall coverage is nominal. The station 15 pass on Tuesday, Nov 22, and the station 26 pass on Saturday, Nov 26, will be carried out at 240 kbps. * Behind has 70 meter passes on Tuesday, Nov 22 (D63 and D14), Wednesday, Nov 23 (D14 at 720 kbps), Thursday, Nov 24 (D14), and Friday, Nov 25 (D14 at 720 kbps). There are 13 passes during the week, and overall coverage is nominal. * The battery discharge cycle on Behind originally scheduled for Nov. 22 has been postponed to Dec 8. Week 48 (Nov 28-Dec 4) * A replay of the SECCHI stepped calibration roll on Ahead for aphelion is scheduled for Tuesday, Nov 29, starting at 09:00 UT. System momentum is expected to be 5 N-m-s. This will be the 19th SECCHI stepped calibration roll on Ahead. * The MOPs macro changes will be written to EEPROM on both spacecraft on Wednesday, Nov 30. * Friday, Dec 2, marks the end of the use of the 34 meters with the low gain antenna (LGA) for emergencies. Use of the LGA with 70 meter stations will continue through the rest of the mission, though this use will be restricted to higher elevations later in the mission. * Ahead has 70 meter passes on Monday, Nov 28 (D63), Tuesday, Nov 29 (D63 and D14), and Wednesday, Nov 30 (D14). There are 12 passes during the week, and overall coverage is nominal. The station 54 and 15 passes on Friday, Dec 2, and the station 55 pass on Saturday, Dec 3, will be carried out at 240 kbps. * Behind has 70 meter passes on Monday, Nov 28 (D63), Wednesday, Nov 30 (D14), Thursday, Dec 1 (D63), Friday, Dec 2 (D63), and Sunday, Dec 4 (D63). There are 13 passes during the week, and overall coverage is nominal. The station 15 pass on Thursday, Dec 1, will be carried out at 240 kbps. Week 49 (Dec 5-11) * A second data flow test with ESA is scheduled for Tuesday, Dec 6, 15-17 UT. Old data will be flowing during this time. * A battery discharge cycle on Behind is scheduled for Dec 8, 14:00-14:18 UT. * Ahead has 70 meter passes on Tuesday, Dec 6 (D63), Wednesday, Dec 7 (D14), Thursday, Dec 8 (D14), Saturday, Dec 10 (D14, D43 at 720 kbps), and Sunday, Dec 11 (D14). There are 11 passes during the week, and overall coverage is nominal. The station 26 passes on Monday and Thursday will be carried out at 240 kbps. * Behind has 70 meter passes on Monday, Dec 5 (D63), Wednesday, Dec 7 (D14), Thursday, Dec 8 (D63), and Saturday, Dec 10 (D14). There are 13 passes during the week, and overall coverage is nominal. Week 50 (Dec 12-18) * Ahead has 70 meter passes on Monday, Dec 12 (D63 at 720 kbps), Wednesday, Dec 14 (D14 at 720 kbps), Thursday, Dec 15 (D14), Saturday, Dec 17 (D63), and Sunday, Dec 18 (D14, D43 at 720 kbps). There are 11 passes during the week, and overall coverage is nominal. * Behind has 70 meter passes on Monday, Dec 12 (D63), Friday, Dec 16 (D43), and Sunday, Dec 18 (D63). The station 25 pass on Dec 15 will be carried out at 240 kbps. Week 51 (Dec 19-25) * Ahead has 70 meter passes every day during the week. The station 14 pass on Wednesday, Dec 21 will be carried out at 720 kbps. There are 9 passes during the week, and overall coverage is nominal. * Behind has 70 meter passes on Monday, Dec 19 (D63), Tuesday, Dec 20 (D63), Wednesday, Dec 21 (D63), Friday, Dec 23 (D43 at 720 kbps), Saturday, Dec 24 (D14 at 720 kbps), and Sunday, Dec 25 (D63). There are 11 passes during the week, and overall coverage is nominal. The station 15 pass on Dec 21 will be carried out at 240 kbps. Other * SECCHI asked about the ground scheduling software modifications. These are expected sometime before the end of November. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 46: M Nov 14 (318) Ahead: 70 meter downlink on station 14 T Nov 15 (319) Ahead: Momentum dump, 16:30 UT Ahead: 70 meter downlink on station 14 Behind: 70 meter downlink on station 14 W Nov 16 (320) Behind: Momentum dump, 22:00 UT Behind: 70 meter downlink on station 14 T Nov 17 (321) Behind: 70 meter downlink on station 43 F Nov 18 (322) Ahead: 70 meter downlink on station 63 S Nov 19 (323) Ahead: 70 meter downlink on station 63 S Nov 20 (324) Notes: * Behind test with DSS 15, Nov. 16 14:15-16:15 UT, using simulated data ------------------------------------------------------------------------------- Scheduled activities for Week 47: M Nov 21 (325) T Nov 22 (326) Behind: 70 meter downlink on stations 63 and 14 W Nov 23 (327) Ahead: 70 meter downlink on station 14 Behind: 70 meter downlink on station 14 T Nov 24 (328) Thanksgiving Behind: 70 meter downlink on station 14 F Nov 25 (329) Behind: 70 meter downlink on station 14 S Nov 26 (330) S Nov 27 (331) Notes: * Both Thursday and Friday, Nov 24-25, are holidays at APL. ------------------------------------------------------------------------------- Scheduled activities for Week 48: M Nov 28 (332) Ahead: 70 meter downlink on station 63 Behind: 70 meter downlink on station 63 T Nov 29 (333) Ahead: SECCHI stepped calibration roll, 09:00 UT Ahead: 70 meter downlink on stations 63 and 14 W Nov 30 (334) Ahead: 70 meter downlink on station 14 Behind: 70 meter downlink on station 14 T Dec 01 (335) Behind: 70 meter downlink on station 63 F Dec 02 (336) Behind: 70 meter downlink on station 63 S Dec 03 (337) S Dec 04 (338) Behind: 70 meter downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 49: M Dec 05 (339) Behind: 70 meter downlink on station 63 T Dec 06 (340) Ahead: 70 meter downlink on station 63 W Dec 07 (341) Ahead: 70 meter downlink on station 14 Behind: 70 meter downlink on station 14 T Dec 08 (342) Ahead: 70 meter downlink on station 14 Behind: 70 meter downlink on station 63 F Dec 09 (343) S Dec 10 (344) Ahead: 70 meter downlink on stations 14 and 43 Behind: 70 meter downlink on station 14 S Dec 11 (345) Ahead: 70 meter downlink on station 14 Notes: * Ahead test with ESA reference station Dec 6, 15-17 UT, using simulated data ------------------------------------------------------------------------------- Scheduled activities for Week 50: M Dec 12 (346) Ahead: 70 meter downlink on station 63 Behind: 70 meter downlink on station 63 T Dec 13 (347) W Dec 14 (348) Ahead: 70 meter downlink on station 14 T Dec 15 (349) Ahead: 70 meter downlink on station 14 F Dec 16 (350) Behind: 70 meter downlink on station 43 S Dec 17 (351) Ahead: 70 meter downlink on station 63 S Dec 18 (352) Ahead: 70 meter downlink on stations 14 and 43 Behind: 70 meter downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 51: M Dec 19 (353) Ahead: 70 meter downlink on station 63 Behind: 70 meter downlink on station 63 T Dec 20 (354) Ahead: 70 meter downlink on station 14 Behind: 70 meter downlink on station 63 W Dec 21 (355) Ahead: 70 meter downlink on station 14 Behind: 70 meter downlink on station 63 T Dec 22 (356) Ahead: 70 meter downlink on station 14 F Dec 23 (357) Ahead: 70 meter downlink on station 63 Behind: 70 meter downlink on station 43 S Dec 24 (358) Ahead: 70 meter downlink on station 14 Behind: 70 meter downlink on station 14 S Dec 25 (359) Ahead: 70 meter downlink on station 14 Behind: 70 meter downlink on station 63 ------------------------------------------------------------------------------- Upcoming events: 2012: * Jan 11 Both: HGA calibration * 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