STEREO Weekly Meeting Minutes for 2013-08-27 (Week 35) ANNOUNCEMENTS ------------- * The DMZ work scheduled for Tuesday, Aug 27, has been postponed until some time late in September. * Different DMZ maintenance activities are scheduled for Thursday, Aug 29, between 2-4 UT. * The 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. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 34 (Aug 19-25) * On day 232 (Aug 20), during the DSS-14 support for ahead, telemetry was delayed one hour until 2155z due to an X-band maser problem. The SSR pointers were repositioned prior to the outage. The telemetry outage and pointer repositioning eventually resulted in 8.1 hours of SECCHI data loss on day 234 (Aug 22). The turbo decoder lock was lost intermittently between 2306z and 2307z. The turbo decoder anomaly resulted in the loss of 752 frames of SSR data. The transmitter tripped offline at 2319z, but had no impact on operations since all command activity was complete. See DRs #G114169, #N109083, and #G114171 respectively for more information. * On day 234 (Aug 22), during the DSS-43 support for Ahead, telemetry was lost from 235-0013z through 235-0021z due to the antenna brakes being applied. Also, the turbo decoder lock was lost intermittently beginning at 235-0047z through 2350049z. These anomalies resulted in the loss 28337 frames of SSR data. See DR #C109507 for more information. * On day 235 (Aug 23), during the DSS-24 support for Ahead, turbo decoder lock was lost intermittently beginning at 1433z through 1741z. This anomaly resulted in the loss of 337 frames of SSR data. See DR #N109084 for more information. * On day 234 (Aug 22), the SSR science partitions on Ahead filled as follows: SECCHI (Part 19) reached 100% full at 0829z for 5.7 hours. SECCHI (Part 19) reached 100% full at 1821z for 2.4 hours. The cause was the DSS-14 antenna problem and SSR pointer repositioning on DOY 232. * On day 231 (Aug 19), during the DSS-15 support for Behind, turbo decoder lock was lost briefly at 2220z. This anomaly resulted in the loss of one frame of SSR data. * On day 232 (Aug 20), during the DSS-65 support for Behind, turbo decoder lock was lost briefly at 1300z. This anomaly resulted in the loss of four frames of SSR data. * On day 233 (Aug 21), during the DSS-63 support for Behind, turbo decoder lock was lost intermittently beginning at 1637z through 1849z. This anomaly resulted in the loss of 3668 frames of SSR data. See DR #M107482 for more information. * On day 234 (Aug 22), during the DSS-14 support for Behind, telemetry was delayed by eight minutes until 1628z due to maintenance for a transmitter problem. Commanding was not conducted because the transmitter remained red for the entire track. This anomaly resulted in the loss of six minutes of SSR playback data. See DR #G114188 for more information. * On day 236 (Aug 24), during the DSS-25 support for Behind, turbo decoder lock was lost intermittently beginning at 2127z through 2370017z. This anomaly resulted in the loss of 6065 frames of SSR data. See DR #G114195 for more information. * On day 234 (Aug 22), the SECCHI instrument on Behind reset at 17:12:29z. The SECCHI team reconfigured the instrument to operational mode at 235-1600z the next day. This was the 21st reset of SECCHI on the Behind spacecraft. * The average daily SSR playback volume during the week was 3.4 gigabits for Ahead, and 3.3 gigabits on Behind. Week 35 (Aug 26-Sep 1) * Ahead has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Aug 27 (D43), Friday, Aug 30 (D63), and Sunday, Sep 1 (D63). The following passes will be carried out at 160 kbps: Tuesday, Aug 27 (D54), Wednesday, Aug 28 (D55), and Thursday, Aug 29 (D54). * Behind has 8 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Aug 26 (D63), Wednesday, Aug 28 (D63), Thursday, Aug 29 (D63), and Friday, Aug 30 (D14 at 720 kbps). The station 24 pass on Sunday, Sep 1, will be carried out at 160 kbps. Week 36 (Sep 2-8) * Monday, Sep 2, is Labor Day, which is a holiday at APL. * The 27th SECCHI stepped calibration roll on Ahead is scheduled for Tuesday, Sep 3, starting at 01:45 UT. This will be the aphelion roll. The actual date of aphelion is Friday, Sep 6. * The third battery discharge maintenance activity on Ahead is scheduled for Wednesday, Sep 4, starting at 15:00 UT. * Ahead has 9 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, D43), Saturday, Sep 7 (D63), 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. * 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 about the request for DSN track time for the Comet ISON observations around perihelion on Nov 28. That week is currently being negotiated, and it will be another week or so before it is finalized, after which the scheduler will try to fill in with ESA tracks. So far, the scheduling looks good for achieving nominal coverage, but not so far for the extra requested time. * A preliminary plan for rolling the spacecraft has been distributed by the MOC. the current plan has 3 hour dwell times, plus 18-39 minutes for rolling the spacecraft depending on the roll angle. SECCHI asks whether the dwell times can be adjusted to fill out the total time to 4 hours, with different dwell times for different roll angles. SECCHI also asks that the rolls start on even hour boundaries * LADEE is scheduled to be launched on Friday. There are various launch contingencies if the original launch date is not met, but the possible effect on the DSN schedules for stereo don't look too bad. * Additional launches coming up that can affect the DSN schedules are MOM and MAVEN, both Mars missions. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 35: M Aug 26 (238) T Aug 27 (239) W Aug 28 (240) T Aug 29 (241) F Aug 30 (242) S Aug 31 (243) S Sep 01 (244) ------------------------------------------------------------------------------- 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