STEREO Weekly Meeting Minutes for 2013-09-03 (Week 36) ANNOUNCEMENTS ------------- * The NASA MUG system used for monitoring telemetry will be upgraded on Monday, Sep 30, from 15-17 UT, which is outside track time. The backup date is Thursday, Oct 3, between 12-14 UT, also outside track time. * The LADEE launch is scheduled for Friday evening, Sep 6, at 11:27 P.M. EDT (03:27 UT on Sep 7), with four days of launch contingency. A message has been sent to the instrument teams describing the possible impacts on the STEREO mission of a launch delay. Those located in the Washington area may actually be able to view the launch from Wallops. Details can be found at http://www.orbital.com/NewsInfo/MissionUpdates/MinotaurV/index.shtml * A Go/No-Go meeting for the gyroless mode is planned for Sep 12. If gyroless mode is approved, it will be implemented on Sep 18 on the Ahead spacecraft only. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 35 (Aug 26-Sep 1) * On day 239 (Aug 27), during the DSS-54 support for Ahead, turbo decoder lock was lost intermittently beginning at 1114z through 1115z. This anomaly resulted in the loss of 882 frames of SSR data. See DR #M107493 for more information. * On day 243 (Aug 31), during the DSS-55 support for Ahead, turbo decoder lock was lost briefly at 0923z. This anomaly resulted in the loss of one frame of SSR data. * On day 238 (Aug 26), during the DSS-63 support for Behind, turbo decoder lock was lost intermittently beginning at 1306z through 1758z. This anomaly resulted in the loss of 19750 frames of SSR data. See DR #M107490 for more information. A question was raised about whether this incident was related to the recent problems with station 63 losing lock. DSN reports that they have replaced the downconverter on station 63, but there may be problems with signal stability. They will keep an eye on the performance. * On day 239 (Aug 27), during the DSS-55 support for Behind, turbo decoder lock was lost intermittently beginning at 1324z through 1327z. This anomaly resulted in the loss of 238 frames of SSR data. See DR # M107494 for more information. * On day 241 (Aug 29), during the DSS-63 support for Behind, command bind was aborted at 1510z due to a transmitter glitch. This anomaly had no impact on operations and command bind was reestablished at 1515z. See DR #M107500 for more information. * On day 242 (Aug 30), during the DSS-45 support for Behind, turbo decoder lock was lost briefly at 0815z. This anomaly resulted in the loss of 28 frames of SSR data. * The average daily SSR playback volume during the week was 4.5 gigabits for Ahead, and 4.3 gigabits for Behind. Week 36 (Sep 2-8) * The 27th SECCHI stepped calibration roll on Ahead took place today (Sep 3), starting at 01:45 UT. This was the aphelion roll. The actual date of aphelion is Friday, Sep 6. * The station 43 pass for Ahead on Friday was deleted to support the Deep Impact mission. * The third battery discharge maintenance activity on Ahead is scheduled for Wednesday, Sep 4, starting at 15:00 UT. * Ahead has 8 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Sep 2 (D63), Tuesday, Sep 3 (D63), Thursday, Sep 5 (D43), Friday, Sep 6 (D63), Saturday, Sep 7 (D63 at 720 kbps), and Sunday, Sep 8 (D63). * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Wednesday, Sep 4 (D63), Thursday, Sep 5 (D63, D14), Saturday, Sep 7 (D63 at 720 kbps), and Sunday, Sep 8 (D63). The following passes will be carried out at 160 kbps: Monday, Sep 2 (D45), and Friday, Sep 6 (D55, D24). Week 37 (Sep 9-15) * The 55th momentum dump on Behind is scheduled for Tuesday, Sep 10, starting at 14:00 UT. * The 60th momentum dump on Ahead is scheduled for Thursday, Sep 12, starting at 15:30 UT. * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Sep 9 (D14), Tuesday, Sep 10 (D63), Friday, Sep 13 (D63), and Saturday, Sep 14 (D14). The following passes will be carried out at 160 kbps: Wednesday, Sep 11 (D26), and Saturday, Sep 14 (D65). ESA New Norcia passes are scheduled for Wednesday, Sep 11, and Thursday, Sep 12. * Behind has 9 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Wednesday, Sep 11, Thursday, Sep 12, Friday, Sep 13, and Saturday, Sep 14, all using station 63. The station 45 pass on Monday, Sep 9, will be carried out at 160 kbps, and the station 26 pass on Thursday, Sep 12, will be carried out at 240 kbps. Week 38 (Sep 16-22) * The 26th SECCHI stepped calibration roll on Behind is scheduled for Tuesday, Sep 17, starting at 08:50 UT. This is the midpoint roll. * Reduced gyro operations on the Ahead spacecraft will be deployed on Wednesday, Sep 18, contingent on approval at the Go/No-go meeting the previous week. * Ahead has 7 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Sep 16 (D43), Tuesday, Sep 17 (D63), Thursday, Sep 19 (D14), Friday, Sep 20 (D63), and Saturday, Sep 21 (D63 at 720 kbps). The station 65 pass on Wednesday, Sep 18, will be carried out at 160 kbps. * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Sep 16 (D63 at 720 kbps), Tuesday, Sep 17 (D63 at 720 kbps), Wednesday, Sep 18 (D63), Thursday, Sep 19 (D63), Friday, Sep 20 (D43), and Saturday, Sep 21 (D63). Week 39 (Sep 23-29) * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Sep 23 (D14), Tuesday, Sep 24 (D63), Friday, Sep 27 (D14 at 720 kbps), and Sunday, Sep 29 (D63). The station 54 pass on Thursday, Sep 26, will be carried out at 160 kbps. An ESA New Norcia pass is scheduled for Thursday, Sep 26. * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Sep 23 (D63), Wednesday, Sep 25 (D63), Thursday, Sep 26 (D43 at 720 kbps), and Friday, Sep 27 (D43 at 720 kbsp). Week 40 (Sep 30-Oct 6) * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Oct 1 (D63), Wednesday, Oct 2 (D43 at 720 kbps), Friday, Oct 4 (D14 at 720 kbps), Saturday, Oct 5 (D63), and Sunday, Oct 6 (D63). The following passes will be carried out at 160 kbps, both using station 26: Monday, Sep 30, and Tuesday, Oct 1. An ESA Malargue pass is scheduled for Thursday, Oct 3. * Behind has 12 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Sep 30 (D63 at 720 kbps), Tuesday, Oct 1 (D63 at 720 kbps), Wednesday, Oct 2 (D63), Friday, Oct 4 (D14 twice), and Saturday, Oct 5 (D63). The following passes will be carried out at 160 kbps: Monday, Sep 30 (D34), and Wednesday, Oct 2 (D26). Other * A question was raised whether STEREO was planning to observe Comet ISON during late September to early October. This is the period when the comet is close to Mars, and the MRO mission is asking for additional track time during this period. Comet ISON won't enter into the field-of-view of either STEREO spacecraft until Oct 10, and spacecraft rolls for the comet won't begin until Oct 24. Additional track time for STEREO has been requested starting Oct 24. Thus, there are no conflicts with the Mars mission, but there is a potential for conflicts with MESSENGER when the comet passes close to Mercury in mid-November. The schedulers have not heard of any special requests for telemetry time from the MESSENGER mission. * The MOC has received an advance copy of the DSN schedule for week 48, containing Comet ISON's perihelion, for planning purposes. The MOC plan to carry out SECCHI's request for spacecraft rolls. They anticipate that 1-2 additional momentum dumps may be carried out to keep system momentum low, particularly on the Behind spacecraft. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 36: M Sep 02 (245) Labor Day T Sep 03 (246) Ahead: SECCHI stepped calibration roll, 01:45 UT W Sep 04 (247) Ahead: Battery discharge maintenance, 15:00 UT T Sep 05 (248) F Sep 06 (249) Ahead: Aphelion S Sep 07 (250) S Sep 08 (251) ------------------------------------------------------------------------------- Scheduled activities for Week 37: M Sep 09 (252) T Sep 10 (253) Behind: Momentum dump, 14:00 UT W Sep 11 (254) T Sep 12 (255) Ahead: Momentum dump, 15:30 UT F Sep 13 (256) S Sep 14 (257) S Sep 15 (258) ------------------------------------------------------------------------------- Scheduled activities for Week 38: M Sep 16 (259) T Sep 17 (260) Behind: SECCHI stepped calibration roll, 08:50 UT W Sep 18 (261) T Sep 19 (262) F Sep 20 (263) S Sep 21 (264) S Sep 22 (265) ------------------------------------------------------------------------------- Scheduled activities for Week 39: M Sep 23 (266) T Sep 24 (267) W Sep 25 (268) T Sep 26 (269) F Sep 27 (270) S Sep 28 (271) S Sep 29 (272) ------------------------------------------------------------------------------- Scheduled activities for Week 40: M Sep 30 (273) T Oct 01 (274) W Oct 02 (275) T Oct 03 (276) F Oct 04 (277) S Oct 05 (278) S Oct 06 (279) ------------------------------------------------------------------------------- Upcoming events: 2013: * Oct 10-Nov 23 Ahead: Comet ISON in HI2 field-of-view * Nov 21-28 Ahead: Comet ISON in HI1 field-of-view * Nov 28 Both: Perihelion passage of Comet ISON http://stereo-ssc.nascom.nasa.gov/comet_ison/ * Dec 1-7 Ahead: Comet ISON in HI1 field-of-view * 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 * Sep 07-Nov 15 Behind: Passage of Comet Siding Spring through HI2-B * Oct 15 Behind: End use of 480 kbps on 70 m DSN subnet * Oct 17 Behind: Comet Siding Spring encounter with Mars 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 * Jul 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