STEREO Weekly Meeting Minutes for 2013-12-10 (Week 50) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 49 (Dec 2-8) * On day 336 (Dec 2), the 3rd SECCHI 290 degree comet ISON roll for Behind was executed successfully at 02:00 UT. * On day 337 (Dec 3), during the DSS-15 support for Ahead, the track was terminated one hour early at 19:35 UT due to antenna problems. The SSR playback was stopped before releasing the antenna to prevent data loss. See DR# G114455 more information. * On day 337 (Dec 3), the 4th SECCHI 290 degree comet ISON roll for Behind was executed successfully at 00:01 UT. * On day 338 (Dec 4), during the DSS-43 support for Behind, beginning of track was delayed seven minutes until 04:37 UT due to antenna software problems. This anomaly resulted in the loss of seven minutes of SSR playback data. See DR# C109641 more information. * On day 338 (Dec 4), the 1st SECCHI 30 degree roll for Ahead and the 5th SECCHI 290 degree roll for Behind to observed comet ISON were executed successfully at 00:01 UT. * On day 339 (Dec 5), the DSS-15 support for Ahead was cancelled due to maintenance for antenna problems. No other stations were available for tracking to prevent SSR data loss. * On day 339, the SSR science partitions on Ahead filled as follows: SECCHI (Part 19) reached 100% full at 22:45 UT for 9.3 hours. This was caused by the cancelled DSS-15 track at 339-14:40 UT. * On day 339 (Dec 5), the 2nd SECCHI 30 degree roll for Ahead and the the 6th SECCHI 290 degree roll for Behind to observe comet ISON were executed successfully at 00:01 UT. * On day 340 (Dec 6), during the DSS-63 support, turbo decoder lock for Ahead was lost briefly at 12:17 UT. This anomaly resulted in the loss of one frame of SSR data. * On day 340 (Dec 6), the 3rd SECCHI 30 degree comet ISON roll for Ahead was executed at 00:01 UT, but the images were not recorded because the SECCHI SSR science partition was full (see note for day 229 above). The the 7th SECCHI 290 degree comet ISON roll for Behind was executed successfully at 00:01 UT. * On day 341 (Dec 7), the 8th SECCHI 290 degree comet ISON roll for Behind was executed successfully at 02:00 UT. * On day 342 (Dec 8), the DSS-43 support for Ahead was relinquished to assist Odyssey safehold recovery operations. MOps had planned on moving all SSR pointers back during the subsequent day 343 DSS-63 support, however transmitter issues prevented any attempt at data recovery. Therefore, the deleted D SS-43 track resulted in the loss of 4 hours of SSR data for all instruments. See DR# M107603 more information. * On day 342 (Dec 8), during the DSS-26 support for Behind, turbo decoder lock was lost briefly at 18:08 UT and again at 2157 UT. This anomaly resulted in the loss of 2 frames of SSR data. * The average daily SSR playback volume during this week was 3.7 Gbits for both Ahead and Behind. Week 50 (Dec 9-15) * Simultaneous 30 degree rolls of Ahead, and 290 degree rolls of Behind, to observe Comet ISON, were carried out Monday and Tuesday (Dec. 9-10) with another scheduled for Wednesday, Dec 11 at 02:00 UT. These will be the final Comet ISON rolls. * Commands will be sent up on Wednesday Dec 11 around 15:00 UT to unlatch Ahead's IMPACT/SEPT North-South instrument. The instrument was latched-up on Dec. 4. * A transit of Mercury across the disk of the Sun will be observed by the Ahead spacecraft on Thursday, Dec 12, between approximately 01:58-07:10 UT. Station 43 downlink pass during that time. The complete period during which Mercury will be visible in either the COR1 or EUVI fields of view ranges from Wednesday, Dec 11, from approximately 11 UT, to Thursday, Dec 12, until approximately 19 UT, though visibility will depend on the coronal brightness behind Mercury. * The 28th SECCHI stepped calibration roll on Ahead is scheduled for Friday, Dec 13, starting at 04:05 UT. * Ahead has 8 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Dec 9 (D63), Tuesday, Dec 10 (D63), Saturday, Dec 14 (D63), and Sunday, Dec 15 (D63). * Behind has 11 passes during the week, and overall coverage is short 12 hours, mainly between Tuesday-Friday, Dec 10-13. A 70 meter pass is scheduled for Friday, Dec 13 (D14). The following passes will be carried out at 160 kbps, both using station 26: Wednesday, Dec 11, and Sunday, Dec 15. A ESA New Norcia pass is scheduled for Friday, Dec 13. The one previously scheduled for Thursday, Dec 12 has been canceled. Week 51 (Dec 16-22) * The third battery discharge cycle on Behind is scheduled for Wednesday, Dec 18, starting at 13:30 UT. * The 63rd momentum dump on Ahead is scheduled for Thursday, Dec 19, with ignition at 13:00 UT. * The 58th momentum dump on Behind is scheduled for Thursday, Dec 19, with ignition at 15:00 UT. * Ahead has 13 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Dec 16 (D63), Tuesday, Dec 17 (D43 at 720 kbps), and Friday, Dec 20 (D63). * Behind has 12 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Dec 17 (D43), and Friday, Dec 20 (D43 at 720 kbps). The following passes will be carried out at 160 kbps, all using station 26: Wednesday, Dec 18, Friday, Dec 20, and Sunday, Dec 22. Week 52 (Dec 23-29) * APL will closed for the Christmas holiday starting the afternoon of Tuesday, Dec 24, and on Christmas Day, Dec 25. * The 27th SECCHI stepped calibration roll for Behind is scheduled for Thursday, Dec 26, starting at 13:10 UT. This is the aphelion roll. * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Dec 23 (D63), Tuesday, Dec 24 (D14), and Friday, Dec 27 (D63). The following passes will be carried out at 160 kbps: Monday, Dec 23 (D45), and Thursday, Dec 26 (D26). * Behind has 14 passes during the week, and overall coverage is nominal. A 70 meter pass is scheduled for Saturday, Dec 28 (D43 at 720 kbps). The following passes will be carried out at 160 kbps: Tuesday, Dec 24 (D26), Thursday, Dec 26 (D45), and Saturday, Dec 28 (D26). Week 01 (Dec 30-Jan 5) * APL will be closed for the New Year's Day holiday starting the afternoon of Tuesday, Dec 31, and on Jan 1. * Ahead has 8 passes during the week. Overall coverage is short 18.4 hours, between Monday-Friday, Dec 30-Jan 3. 70 meter passes are scheduled for Tuesday, Dec 31 (D63), and Friday, Jan 3 (D63). The station 26 pass on Sunday, Jan 5, will be carried out at 160 kbps. * Behind has 8 passes during the week. Overall coverage is short 16.4 hours, between Monday-Friday, Dec 30-Jan 3. 70 meter passes are scheduled for Saturday, Jan 4 (D63 at 720 kbps, D14). The following passes will be carried out at 160 kbps: Wednesday, Jan 1 (D25), and Sunday, Jan 5 (D25). * Data loss for Behind on days when there will be a shortfall will be about 50%. PLASTIC will look into cutting back on their record rate. Week 02 (Jan 6-12) * Ahead 19th high-gain antenna calibration at 19:00 UT on Tuesday, Jan 7. It will take about an hour. * Behind 19th high-gain antenna calibration at 15:00 UT Wednesday, Jan 8. * Ahead has 8 passes during the week. Overall coverage is short 13.6 hours, mainly between Sunday, Jan 5 (of Week 1) and Wednesday, Jan 8. 70 meter passes Thursday, Friday, and Sunday (Jan 9-11). There will be one pass at 160 kbps: Wednesday, Jan 8 (D34) * Behind has 11 passes during the week, and overall coverage is nominal. There are two 70 meter passes, scheduled for Tuesday, Jan 7, and Saturday, Jan 11. Two passes will be carried out at 160 kbps, both on Monday (D45 and D26) Week 03 (Jan 13-19) * The 64th momentum dump on Ahead is scheduled for Thursday, Jan 16 with ignition at 13:30 UT * Ahead has 7 passes during the week. Overall coverage is short 12.2 hours short, mainly Monday-Thursday There are two 70 meter supports scheduled, on Friday, Jan 17, and Saturday, Jan 18. * Behind has 10 passes during the week. Overall coverage is short 15.2 hours, with the shortfalls occurring Monday-Friday. No 70 meter supports. The following passes will be carried out at 160 kbps: Monday, Jan 13 (D26), Tuesday, Jan 14 (D25), and Wednesday, Jan 15 (D55) Week 4 (Jan 20-26) * The 59th momentum dump on Behind is scheduled for Monday, Jan 20, with ignition at 23:00 UT. * Ahead has 9 passes during the week. Overall coverage is short 16.4 hours, spread throughout the week except Saturday. 30-40% data loss most days. * Behind has 10 passes during the week. Overall coverage is short 10.5 hours, with the shortfall Wednesday-Friday. No 70 meter passes are scheduled. The following passes will be carried out at 160 kbps: Thursday, Jan 23 (D26), Friday, Jan 24 (D26), Saturday, Jan 25 (D55), and Sunday, Jan 26 (D26). COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 50: M Dec 09 (343) Ahead: 30 degree roll to observe Comet ISON, 2-6 UT Behind: 290 degree roll to observe Comet ISON, 2-6 UT T Dec 10 (344) Ahead: 30 degree roll to observe Comet ISON, 2-6 UT Behind: 290 degree roll to observe Comet ISON, 2-6 UT W Dec 11 (345) Ahead: 30 degree roll to observe Comet ISON, 2-6 UT Behind: 290 degree roll to observe Comet ISON, 2-6 UT T Dec 12 (346) Ahead: Mercury transit, 2:00-7:20 UT F Dec 13 (347) Ahead: SECCHI stepped calibration roll, 04:05 UT S Dec 14 (348) S Dec 15 (349) Notes: * Significant telemetry shortages are expected for the Behind spacecraft during the week. ------------------------------------------------------------------------------- Scheduled activities for Week 51: M Dec 16 (350) T Dec 17 (351) W Dec 18 (352) Behind: Battery discharge cycle, 13:30 UT T Dec 19 (353) Momentum dumps: Ahead, 13 UT, Behind 15 UT F Dec 20 (354) S Dec 21 (355) S Dec 22 (356) ------------------------------------------------------------------------------- Scheduled activities for Week 52: M Dec 23 (357) T Dec 24 (358) W Dec 25 (359) Christmas T Dec 26 (360) Behind: SECCHI stepped calibration roll, 13:10 UT F Dec 27 (361) S Dec 28 (362) S Dec 29 (363) ------------------------------------------------------------------------------- Scheduled activities for Week 01: M Dec 30 (364) T Dec 31 (365) W Jan 01 (001) New Year T Jan 02 (002) F Jan 03 (003) S Jan 04 (004) S Jan 05 (005) Notes: * Significant telemetry shortages are expected for both spacecraft during the week. ------------------------------------------------------------------------------- Scheduled activities for Week 02: M Jan 06 (006) T Jan 07 (007) Ahead: 19th HGA calibration, 19:00 UT W Jan 08 (008) Behind: 19th HGA calibration, 15:00 UT T Jan 09 (009) F Jan 10 (010) S Jan 11 (011) S Jan 12 (012) Notes: * Significant telemetry shortages are expected for Ahead during the week. ------------------------------------------------------------------------------- Scheduled activities for Week 03: M Jan 13 (013) T Jan 14 (014) W Jan 15 (015) T Jan 16 (016) Ahead: 64th momentum dump, 13:30 UT F Jan 17 (017) S Jan 18 (018) S Jan 19 (019) Notes: * Significant telemetry shortages are expected for both spacecraft during the week. ------------------------------------------------------------------------------- Scheduled activities for Week 04: M Jan 20 (020) Behind: 59th momentum dump, 23:00 UT T Jan 21 (021) W Jan 22 (022) T Jan 23 (023) F Jan 24 (024) S Jan 25 (025) S Jan 26 (026) Notes: * Significant telemetry shortages are expected for both spacecraft during the week. ------------------------------------------------------------------------------- Upcoming events: 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: * Jan 20 - Mar 28 (TBC) Behind: Spacecraft behind Sun * Mar DAWN - Ceres arrival * 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