STEREO Weekly Meeting Minutes for 2013-05-14 (Week 20) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 19 (May 6-12) * On day 128 (May 8), during the DSS-65 support for Ahead, turbo decoder lock was lost intermittently beginning at 0518z through 0521z. This anomaly resulted in the loss of 84 frames of SSR data. See DR #N108832 for more information. * On day 129 (May 9), during the DSS-74 (ESA New Norcia) support for Ahead, telemetry was delayed by 55 minutes until 2305z due to the station downlink rate configuration of 160 Kbps not matching the spacecraft configuration of 120 Kbps. The spacecraft downlink rate was switched to 160 Kbps to match the station. The SSR pointers were repositioned and all SSR data were recovered. ESA station performance is being reviewed to determine how long the 160 kbps can be maintained. * ESA passes will still be scheduled for the 120 kbps rate, and then possibly bumped up to 160 kbps depending on the station performance. DSN-26 is regularly bumped up to the next rate, and the MOC is looking at the performance of the other stations. * On day 131 (May 11), during the DSS-55 support for Ahead, turbo decoder lock was lost intermittently beginning at 0522z through 0830z. This anomaly resulted in the loss of twelve frames of SSR data. See DR #N108848 for more information. * On day 132 (May 12), during the DSS-55 support for Ahead, turbo decoder lock was lost briefly at 0657z and again at 0748z. The anomaly resulted in the loss of five frames of SSR data. See DR #N108849 for more information. * On day 133 (May 13), during the DSS-55 support for Ahead, turbo decoder lock was lost briefly at 0514z and again at 0524z. The anomaly resulted in the loss of two frames of SSR data. See DR #N108850 for more information. * On day 127 (May 7), during the DSS-54 support for Behind, telemetry was lost beginning at 1649z through 1655z due to the antenna brakes being applied. The command uplink was interrupted at 1655z and MOPS elected to remain downlink only for the remainder of the track to avoid further data loss. This anomaly resulted in the loss of six minutes (6402 frames) of SSR data. See DR #M107289 for more information. * On day 128 (May 8), during the DSS-65 support for Behind, turbo decoder lock was lost briefly at 1937z and again at 1938z. This anomaly resulted in the loss of 228 frames of SSR data. See DR #N108834 for more information. * On day 129 (May 9), during the DSS-63 support for Behind, telemetry was delayed by three minutes until 1503z due to an inadvertent symbol rate input entered at the station. The SSR pointers were repositioned and all SSR data were recovered. Also during the track, turbo decoder lock was lost briefly at 1652z. The turbo decoder anomaly resulted in the loss of 113 frames of SSR data. See DRs #M107293 and #N108842 respectively for more information. * On day 133 (May 13), during the DSS-45 support for Behind, turbo decoder lock was lost intermittently beginning at 0102z through 0659z due to heavy rain at the station. This anomaly resulted in the loss of 639 frames of SSR data. See DR #C109358 for more information. * The average daily SSR playback volume during the week was 4.2 gigabits for Ahead, and 4.3 gigabits for Behind. * A question was raised about the fact that the recent average daily playback volumes are below 5 gigabits. It was asked whether this was due to mission contentions, or to the lowered bit rate. The MOC answered that this was due to the lowered bit rate. Week 20 (May 13-19) * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, May 13 (D14), Wednesday, May 15 (D63), Friday, May 17 (D63), and Saturday, May 18 (D63). * Behind has 8 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, May 14 (D14), Thursday, May 16 (D63), and Saturday, May 18 (D63 at 720 kbps). The following passes will be carried out at 160 kbps: Friday, May 17 (D25), and Sunday, May 19 (D54). Week 21 (May 20-26) * Ahead has 13 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, May 21 (D63), Friday, May 24 (D63 at 720 kbps), and Sunday, May 26 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Monday, May 20 (D54), Tuesday, May 21 (D26), and Saturday, May 25 (D54, D26). An ESA New Norcia pass is scheduled for Thursday, May 23, at 160 kbps. * Behind has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Friday, May 24 (D63 at 720 kbps), and Sunday, May 26 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Wednesday, May 22 (D26, D65), and Saturday, May 25 (D26). Week 22 (May 27-Jun 2) * Monday, May 27, is Memorial Day, which is a holiday at APL. * Thursday, May 30, is the 57th Ahead momentum dump at 16:30 UT. * Wednesday, May 29 is a return-to-service track for station D43. There will be no SSR playback or instrument commanding. * Ahead has 9 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, May 27 (D14), Tuesday, May 28 (D63 at 720 kbps), Wednesday, May 29 (D63), Friday, May 31 (D63), and Sunday, Jun 2 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Saturday, Jun 1 (D54). * Behind has 7 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, May 27 (D14 at 720 kbps), Tuesday, May 28 (D63 at 720 kbps), Friday, May 31 (D63 at 720 kbps), and Sunday, Jun 2 (D14 at 720 kbps). The following passes will be carried out at 240 kbps: Wednesday, May 29 (D26), and Saturday, Jun 1 (D26). Week 23 (Jun 3-9) * An engineering demo using station 26 with the STEREO Behind spacecraft will take place on Tuesday, Jun 4. No SSR playback or commanding will be available during this test. The test will use the new X-band and K-band attenuators to look at the strong spaceweather beacon signal. * Wednesday, Jun 5, is the 52nd Behind momentum dump at 18:30 UT. * Ahead has 12 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jun 3 (D63), Tuesday, Jun 4 (D14), Friday, Jun 7 (D63), and Saturday, Jun 8 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Wednesday, Jun 5 (D25) and Sunday, Jun 9 (D15). An ESA New Norcia pass is scheduled for Wednesday, Jun 5. * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, May 27 (D14 at 720 kbps) and Friday, Jun 7 (D63 at 720 kbps). The following passes will be carried out at 160 kbps: Saturday, Jun 8 (D54), and Sunday, Jun 9 (D54). An ESA Malargue pass is scheduled for Tueday, Jun 4, and an ESA New Norcia pass is scheduled for Friday, Jun 7. Week 24 (Jun 10-16) * Tuesday, Jun 11, is the 26th Ahead SECCHI stepped calibration roll at 08:35 UT. * Behind will be at perihelion on Saturday, Jun 15. * Ahead has 13 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Jun 11 (D43), Thursday, Jun 13 (D43), Friday, Jun 14 (D63 at 720 kbps), and Saturday, Jun 15 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Monday, Jun 10 (D26, D15) and Tuesday, Jun 11 (D26). * Behind has 13 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Jun 11 (D63 at 720 kbps), Thursday, Jun 13 (D43), Friday, Jun 14, (D43, D63), and Saturday, Jun 15 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Monday, Jun 10 (D15), Thursday Jun 13 (D25), and Sunday, Jun 16 (D15). The following passes will be carried out at 240 kbps: Monday, Jun 10 (D26). Week 25 (Jun 17-23) * The 25th SECCHI stepped calibration roll on Behind will be carried out on Tuesday, Jun 18, starting at 17:00 UT. * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jun 17 (D63), Thursday, Jun 20 (D14), and Saturday, Jun 22 (D63). The station 26 pass on Friday, Jun 21, will be carried out at 240 kbps. The following passes will be carried out at 160 kbps: Tuesday, Jun 18 (D26), Thursday, Jun 20 (D15), and Sunday, Jun 23 (D25). * Behind has 9 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jun 17 (D14), Wednesday, Jun 19 (D63), Friday, Jun 21 (D63), and Saturday, Jun 22 (D63), all at 720 kbps. The station 54 pass on Sunday, Jun 23, will be carried out at 160 kbps. Week 26 (Jun 24-30) * Ahead has 13 passes during the week, and overall coverage is short 5 hours, mainly on Wednesday. 70 meter passes are scheduled for Monday, Jun 24 (D14), Thursday, Jun 27 (D14, D43), Saturday, Jun 29 (D14 at 720 kbps), and Sunday, Jun 30 (D63 at 720 kbps). The following passes will be carried out at 160 kbps: Tuesday, Jun 25 (D26), and Wednesday, Jun 26 (D65). An ESA New Norcia pass is scheduled for Tuesday, Jun 25. * Behind has 11 passes during the week, and overall coverage is short 9.4 hours, mainly on Wednesday and Thursday. 70 meter passes are scheduled for Tuesday, Jun 25 (D63 at 720 kbps), Friday, Jun 28 (D43, D63 at 720 kbps), Saturday, Jun 29 (D63 at 720 kbsp), and Sunday, Jun 30 (D63 at 720 kbps). The following passes will be carried out at 160 kbps: Wednesday, Jun 26 (D54), Thursday, Jun 27 (D26), and Saturday, Jun 29 (D26). Other * DSN reports that station 63 is back online, and currently looks good. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 20: M May 13 (133) T May 14 (134) W May 15 (135) T May 16 (136) F May 17 (137) S May 18 (138) S May 19 (139) ------------------------------------------------------------------------------- Scheduled activities for Week 21: M May 20 (140) T May 21 (141) W May 22 (142) T May 23 (143) F May 24 (144) S May 25 (145) S May 26 (146) ------------------------------------------------------------------------------- Scheduled activities for Week 22: M May 27 (147) Memorial Day T May 28 (148) W May 29 (149) Ahead: Return-to-service track for D43 T May 30 (150) Ahead: Momentum dump, 16:30 UT F May 31 (151) S Jun 01 (152) S Jun 02 (153) ------------------------------------------------------------------------------- Scheduled activities for Week 23: M Jun 03 (154) T Jun 04 (155) Behind: Engineering demo with station 26 W Jun 05 (156) Behind: Momentum dump, 18:30 UT T Jun 06 (157) F Jun 07 (158) S Jun 08 (159) S Jun 09 (160) ------------------------------------------------------------------------------- Scheduled activities for Week 24: M Jun 10 (161) T Jun 11 (162) Ahead: SECCHI stepped calibration roll, 08:35 UT W Jun 12 (163) T Jun 13 (164) F Jun 14 (165) S Jun 15 (166) Behind: Perihelion S Jun 16 (167) ------------------------------------------------------------------------------- Scheduled activities for Week 25: M Jun 17 (168) T Jun 18 (169) Behind: SECCHI stepped calibration roll, 17:00 UT W Jun 19 (170) T Jun 20 (171) F Jun 21 (172) S Jun 22 (173) S Jun 23 (174) ------------------------------------------------------------------------------- Scheduled activities for Week 26: M Jun 24 (175) T Jun 25 (176) W Jun 26 (177) T Jun 27 (178) F Jun 28 (179) S Jun 29 (180) S Jun 30 (181) Notes: * Significant telemetry shortages are expected during the week for both spacecraft. ------------------------------------------------------------------------------- Upcoming events: 2013: * Nov 28 Both: Perihelion passage of Comet ISON http://stereo-ssc.nascom.nasa.gov/comet_ison/ * 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