STEREO Weekly Meeting Minutes for 2018-11-20 (Week 47) ANNOUNCEMENTS ------------- * Debbie Knapp will be replacing David Quinn as Mission Director, after 9 years of service to STEREO. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * Ahead is operating nominally. * Four years after the initial loss of communications anomaly with the Behind observatory, NASA has directed to cease periodic recovery operations with the last support on October 17, 2018. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 46 (Nov 12-18) * On day 316 (Nov 12), during the ESA New Norcia (DSS-74) support for Ahead, initial acquisition of telemetry was 34 minutes late at 1155z due to a problem with the station's primary telemetry chain. Later in the support at 1418z, there was an issue with the primary command chain that required a chain reset. These anomalies resulted in the loss of 34 minutes of realtime telemetry and the loss of 2241 frames of SSR data during the uplink 1-way to 2-way transition. See DR #N111006 for more information. * On day 317 (Nov 13), during the DSS-83 (ESA Cebreros) support for Ahead, initial telemetry in the MOC was delayed by eight minutes due to a problem with the station's primary telemetry chain. All SSR data were recovered via an SLE offline data transfer after the track. * On day 320 (Nov 16), during the DSS-14 support for Ahead, beginning of track was delayed 45 minutes at 1234z due to a sub-reflector circuit board problem that occurred before the track. Maintenance reset the circuit board to correct the problem. The SSR pointers were repositioned and all data were recovered. See DR #G119552 for more information. * On day 322 (Nov 18), during the DSS-34 support for Ahead, turbo decoder lock was lost briefly at 323-0016z and again at 323-0144z. This anomaly resulted in the loss of six frames of SSR data. * On day 316 (Nov 12), the 114th momentum dump on Ahead was executed successfully at 1430z, which imparted an estimated delta V of 0.095 m/sec. This was the 33rd momentum dump that did not use the IMU. After thruster operations completed, there was a 0.84 degree of roll angle error. Fine pointing stabilized 2.1 minutes after completion of the momentum dump. * The average daily science data return for Ahead was 4.8 Gbits during this week. Week 47 (Nov 19-25) * Thursday, Nov 22, is Thanksgiving. Both Thursday and Friday are holidays at APL. * Ahead has twelve passes during the week, and overall coverage is nominal. There are four passes at 720 kbps, one at 360 kbps, three at 240 kbps, and four at 160 kbps, including ESA Cebreros passes on Wednesday and Friday. Week 48 (Nov 26-Dec 2) * The restricted IONet backup link will be upgraded at Goddard between 13-18 UT on Monday, Nov 26. * Chanukah starts on Dec 2, and runs though Dec 10. * Ahead has ten passes during the week, and overall coverage is nominal. There are four passes at 720 kbps, four at 360 kbps, one at 240 kbps, and one at 160 kbps. Week 49 (Dec 3-9) * Ahead has nine passes during the week, and overall coverage is nominal. There are four passes at 720 kbps, three at 360 kbps, and two at 240 kbps. Week 50 (Dec 10-16) * Ahead has ten passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, one at 360 kbps, two at 240 kbps, and one at 160 kbps, including an ESA New Norcia pass on Thursday, Dec 13. Week 51 (Dec 17-23) * The 115th momentum dump on Ahead is scheduled for Wednesday, Dec 19, with ignition at 17:00 UT. This will be the 34th dump without using the gyros. This dump will be occuring during an ESA pass. * Ahead has twelve passes during the week, and overall coverage is nominal. There are four passes at 720 kbps, two at 360 kbps, two at 240 kbps, and four at 160 kbps, including two ESA Cebreros passes. Week 52 (Dec 24-30) * Dec 25 is Christmas. Dec 24 is also a holiday for APL. * Ahead has twelve passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, two at 360 kbps, one at 240 kbps, and three at 160 kbps. Week 1 (Dec 31-Jan 6) * Tuesday, Jan 1, is the New Year's Day holiday. Monday, Dec 31 is also a holiday at APL. * On Thursday, Jan 3, the Ahead spacecraft resumes emergency rates of 120 bps upload and 633 bps download, using the LGA with a 70 meter station. * Ahead has eleven passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, two at 360 kbps, and one at 160 kbps. Week 2 (Jan 7-13) * Ahead has nine passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, two at 360 kbps, and one at 240 kbps. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 47: M Nov 19 (323) T Nov 20 (324) W Nov 21 (325) T Nov 22 (326) Thanksgiving F Nov 23 (327) S Nov 24 (328) S Nov 25 (329) ------------------------------------------------------------------------------- Scheduled activities for Week 48: M Nov 26 (330) T Nov 27 (331) W Nov 28 (332) T Nov 29 (333) F Nov 30 (334) S Dec 01 (335) S Dec 02 (336) ------------------------------------------------------------------------------- Scheduled activities for Week 49: M Dec 03 (337) T Dec 04 (338) W Dec 05 (339) T Dec 06 (340) F Dec 07 (341) S Dec 08 (342) S Dec 09 (343) ------------------------------------------------------------------------------- Scheduled activities for Week 50: M Dec 10 (344) T Dec 11 (345) W Dec 12 (346) T Dec 13 (347) F Dec 14 (348) S Dec 15 (349) S Dec 16 (350) ------------------------------------------------------------------------------- Scheduled activities for Week 51: M Dec 17 (351) T Dec 18 (352) W Dec 19 (353) Ahead: Momentum dump, 17:00 UT T Dec 20 (354) F Dec 21 (355) S Dec 22 (356) S Dec 23 (357) ------------------------------------------------------------------------------- Scheduled activities for Week 52: M Dec 24 (358) Christmas Eve (APL holiday) T Dec 25 (359) Christmas W Dec 26 (360) T Dec 27 (361) F Dec 28 (362) S Dec 29 (363) S Dec 30 (364) ------------------------------------------------------------------------------- Scheduled activities for Week 01: M Dec 31 (365) New Year's Eve (APL holiday) T Jan 01 (001) New Year's Day W Jan 02 (002) T Jan 03 (003) F Jan 04 (004) S Jan 05 (005) S Jan 06 (006) ------------------------------------------------------------------------------- Scheduled activities for Week 02: M Jan 07 (007) T Jan 08 (008) W Jan 09 (009) T Jan 10 (010) F Jan 11 (011) S Jan 12 (012) S Jan 13 (013) ------------------------------------------------------------------------------- Upcoming events: Behind events are contingent on recovering the spacecraft. 2019: * Mar Ahead: Switch downlink rate to 240 kbps for 34 meter * Mar 31-Apr 10 Parker Solar Probe perihelion pass * Apr Behind: Switch downlink rate to 240 kbps for 34 meter * Aug 28-Sep 7 Parker Solar Probe perihelion pass * Nov 4 Ahead: Close approach of Parker Solar Probe 2020: * Jan 24-Feb 4 Parker Solar Probe perihelion pass * May Behind: Switch downlink rate to 360 kbps for 34 meter * Jun Ahead: Switch downlink rate to 360 kbps for 34 meter * Jun Behind: Switch downlink rate to 480 kbps for 34 meter * Jun 2-13 Parker Solar Probe perihelion pass * Sep Ahead: Switch downlink rate to 480 kbps for 34 meter * Sep 22-Oct 2 Parker Solar Probe perihelion pass 2021: * Jan 13-23 Parker Solar Probe perihelion pass * Apr 25-May 4 Parker Solar Probe perihelion pass * Jul Behind: Switch downlink rate to 720 kbps for 34 meter * Aug Ahead: Switch downlink rate to 720 kbps for 34 meter * Aug 5-15 Parker Solar Probe perihelion pass * Nov 17-26 Parker Solar Probe perihelion pass 2022: * Feb 21-Mar 2 Parker Solar Probe perihelion pass * May 28-Jun 7 Parker Solar Probe perihelion pass * Sep 2-11 Parker Solar Probe perihelion pass * Dec 7-16 Parker Solar Probe perihelion pass 2023: * Mar 13-23 Parker Solar Probe perihelion pass * May 5 Behind: Mercury transit * Jun 17-27 Parker Solar Probe perihelion pass * Jul 17 Behind: Closest approach to Earth * Aug 13 Ahead: Closest approach to Earth * Sep 23-Oct 3 Parker Solar Probe perihelion pass * Dec 25-Jan 3 Parker Solar Probe perihelion pass 2024: * Mar 26-Apr 4 Parker Solar Probe perihelion pass * Jun 26-Jul 5 Parker Solar Probe perihelion pass * Sep 26-Oct 5 Parker Solar Probe perihelion pass * Dec 20-29 Parker Solar Probe perihelion pass 2025: * Mar 19-27 Parker Solar Probe perihelion pass * Apr 7 Ahead: Mercury transit * Jun 15-24 Parker Solar Probe perihelion pass 2026: 2027: * Feb 1 Behind: Mercury transit 2028: 2029: * Jun 30 Ahead: Mercury transit