STEREO Weekly Meeting Minutes for 2018-06-19 (Week 25) ANNOUNCEMENTS ------------- * None INSTRUMENT and SPACECRAFT STATUS -------------------------------- * Ahead is operating nominally on the main lobe of the high gain antenna. * Behind has transitioned to a monthly schedule to attempt to recover the spacecraft. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 24 (Jun 11-17) * On day 165 (Jun 14), during the DSS-43 support for Ahead, turbo decoder lock was lost briefly at 0315z. This anomaly resulted in the loss of 1 frame of SSR data. * On day 166 (Jun 15), during the DSS-14 support for Ahead, telemetry binds were lost at 167-0000z due to unscheduled JPL network maintenance. This anomaly resulted in the loss of 1.75 hours of real-time telemetry. All SSR data were recovered. * The average daily science data return for Ahead was 5.9 Gbits during this week. * On day 163 (Jun 12), during a 3 hour 4 kHz battery recovery search pattern support for Behind with DSS-14, monitor data was delayed 1.3 hours due to an issue from the scheduled JPL network maintenance. 286 commands were transmitted during the support. This anomaly resulted in loss of commanding for the first point on the search pattern. All remaining points on the pattern were covered twice. See DR #N110945 for more information. * On day 165 (Jun 14), during a 3 hour 4 kHz carrier recovery search pattern support for Behind with DSS-14, 320 commands were transmitted during the support for carrier recovery. No carrier was detected by the DSN station. All 7 points on the pattern were covered twice. Three commands must be received sequentially to power on the transmitter. * On day 166 (Jun 15), during a 3 hour 4 kHz carrier recovery search pattern support for Behind with DSS-14, 320 commands were transmitted during the support for carrier recovery. No carrier was detected by the DSN station. All 7 points on the pattern were covered twice. Three commands must be received sequentially to power on the transmitter. * The JPL network was down for maintenance twice during the week: a scheduled activity on Tuesday which affected the Behind pass, and an unscheduled (or unannounced) activity on Friday which affected an Ahead pass. Week 25 (Jun 18-24) * The 110th momentum dump on Ahead is scheduled for Thursday, Jun 21, with ignition at 20:00 UT. This will be the 29th dump without using the gyros. * Ahead has 11 tracks during the week, and overall coverage is nominal. There are six tracks at 720 kbps, three at 360 kbps, and two at 240 kbps. * There are no recovery passes for Behind during the week. Week 26 (Jun 25-Jul 1) * Ahead has eleven tracks during the week, and overall coverage is now nominal after a 70 meter pass was added on Monday. There are seven tracks at 720 kbps, and four at 240 kbps. * There are no recovery passes for Behind during the week. Week 27 (Jul 2-8) * A return-to-service pass for station 25 with Ahead is scheduled for Tuesday, Jul 3. There will be no SSR playback or instrument commanding during this pass. * Wednesday, Jul 4, is Independence Day, which is a holiday at APL. * Ahead has ten tracks during the week, and overall coverage is nominal. There are five tracks at 720 kbps, three at 360 kbps, and two at 240 kbsp. * There are no recovery passes for Behind during the week. Week 28 (Jul 8-15) * Ahead has twelve tracks during the week, and overall coverage is nominal. There are three tracks at 720 kbps, three at 360 kbps, and six at 240 kbps. * Recovery tracks for Behind using the 1 kHz frequency acquisition sequence are scheduled for Monday, Jul 9 (battery), and Tuesday, Jul 10 and Wednesday, Jul 11 (both carrier). Week 29 (Jul 16-22) * Ahead has 16 tracks during the week, and overall coverage is nominal. There are four tracks at 720 kbps, three at 360 kbps, and nine at 240 kbps. * There are no recovery passes for Behind during the week. Week 30 (Jul 23-29) * The 111th momentum dump on Ahead is scheduled for Tuesday, Jul 24, with ignition at 20:30 UT. This will be the 30th dump without using the gyros. * Ahead has 11 tracks during the week, and overall coverage is nominal. There are two tracks at 720 kbps, four at 360 kbps, and 5 at 240 kbps. * There are no recovery passes for Behind during the week. Week 31 (Jul 30-Aug 5) * Ahead has 10 tracks during the week, and overall coverage is nominal. There are five tracks at 720 kbps, two at 360 kbps, two at 240 kbps, and one at 160 kbps. * There are no recovery passes for Behind during the week. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 25: M Jun 18 (169) T Jun 19 (170) W Jun 20 (171) T Jun 21 (172) Ahead: Momentum dump, 20:00 UT F Jun 22 (173) S Jun 23 (174) S Jun 24 (175) ------------------------------------------------------------------------------- Scheduled activities for Week 26: M Jun 25 (176) T Jun 26 (177) W Jun 27 (178) T Jun 28 (179) F Jun 29 (180) S Jun 30 (181) S Jul 01 (182) ------------------------------------------------------------------------------- Scheduled activities for Week 27: M Jul 02 (183) T Jul 03 (184) Ahead: Return-to-service track with station 25 W Jul 04 (185) Independence Day T Jul 05 (186) F Jul 06 (187) S Jul 07 (188) S Jul 08 (189) ------------------------------------------------------------------------------- Scheduled activities for Week 28: M Jul 09 (190) Behind: Recovery track, DSN 14 (1 kHz, battery) T Jul 10 (191) Behind: Recovery track, DSN 43 (1 kHz, carrier) W Jul 11 (192) Behind: Recovery track, DSN 43 (1 kHz, carrier) T Jul 12 (193) F Jul 13 (194) S Jul 14 (195) S Jul 15 (196) ------------------------------------------------------------------------------- Scheduled activities for Week 29: M Jul 16 (197) T Jul 17 (198) W Jul 18 (199) T Jul 19 (200) F Jul 20 (201) S Jul 21 (202) S Jul 22 (203) ------------------------------------------------------------------------------- Scheduled activities for Week 30: M Jul 23 (204) T Jul 24 (205) Ahead: Momentum dump, 20:30 UT W Jul 25 (206) T Jul 26 (207) F Jul 27 (208) S Jul 28 (209) S Jul 29 (210) ------------------------------------------------------------------------------- Scheduled activities for Week 31: M Jul 30 (211) T Jul 31 (212) W Aug 01 (213) T Aug 02 (214) F Aug 03 (215) S Aug 04 (216) S Aug 05 (217) ------------------------------------------------------------------------------- Upcoming events: Behind events are contingent on recovering the spacecraft. 2019: * Mar Ahead: Switch downlink rate to 240 kbps for 34 meter * Apr Behind: Switch downlink rate to 240 kbps for 34 meter 2020: * 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 * Sep Ahead: Switch downlink rate to 480 kbps for 34 meter 2021: * Jul Behind: Switch downlink rate to 720 kbps for 34 meter * Aug Ahead: Switch downlink rate to 720 kbps for 34 meter 2022: 2023: * May 5 Behind: Mercury transit * Jul 17 Behind: Closest approach to Earth * Aug 13 Ahead: Closest approach to Earth 2024: 2025: * Apr 7 Ahead: Mercury transit 2026: 2027: * Feb 1 Behind: Mercury transit 2028: 2029: * Jun 30 Ahead: Mercury transit