STEREO Weekly Meeting Minutes for 2023-05-23 (Week 21) ANNOUNCEMENTS ------------- * None INSTRUMENT and SPACECRAFT STATUS -------------------------------- * Ahead is operating nominally. PLASTIC is in operational mode, but with a moderately higher than normal background rate. * 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 20 (May 15-21) * On day 135 (May 15), during the DSS-14 support for Ahead, turbo decoder lock was lost briefly at 0303z, due to an elevation tracking error caused by a faulty tachometer. This anomaly resulted in the loss of 102 frames of real-time data. All the affected data was recovered during the subsequent DSS-63 track. See DR #G123720 for more information. * On day 136 (May 16), during the DSS-25 support for Ahead, the station dropped telemetry briefly at 2053z, due to a short disconnection from the data server. This anomaly resulted in the loss of two minutes of real-time and SSR data. See DR #G123721 for more information. * On day 138 (May 18), during the DSS-14 support, turbo decoder lock was lost intermittently between 0324z and 0327z, due to an elevation tracking error caused by a faulty tachometer. This anomaly resulted in the loss of 121 frames of real-time and SSR data. The MOPs team repositioned the SSR pointers during the subsequent DSS-63 track and recovered all the affected data. See DR #G123719 for more information. The elevation tracker on station 14 was repaired later on day 138. * On days 137-139 (May 17-19), DSN conducted a Madrid Complex maintenance from 1030z through 1430z each day. The maintenance activity did not impact the MOC and the Madrid tracks were successful each day. * On day 135 (May 15), the 156th momentum dump on Ahead was executed successfully at 2100z, which imparted an estimated delta V of 0.055 m/sec. This was the 75th momentum dump conducted without gyro use. After thruster operations completed, there was a 0.18 degree of roll angle error. Fine pointing stabilized 3.3 minutes after completion of the momentum dump. * As of day 141 (May 21), all PLASTIC systems on Ahead are behaving well, except there is a moderate background count rate, which the team is continuing to monitor. * The average daily science data return for Ahead was 6.4 Gbits during this week. * The SECCHI team reported that the COR1 background was higher when observations resumed after the momentum dump on May 15. This is attributed to a piece of dust adhering to the front objection. Similar increases have been seen in the past. It is not known whether this was caused by the momentum dump. Week 21 (May 22-28) * Ahead has eleven tracks during the week, all at 720 kbps, and overall coverage is nominal. * A return to service demo track with Station 43 is scheduled for Thursday, May 25 03:10 - 05:10 UT. There will be no instrument commanding or SSR playback for that track. * Work will be done on the APL commercial power starting at 9:30 UT on Saturday, May 27 (day 147), and ending around 21:00 UT on Sunday, May 28 (day 148). The MOC will be on generator power during this period. Week 22 (May 29-Jun 4) * Ahead has nine tracks during the week, all at 720 kbps, and overall coverage is nominal. * APL will be closed on Monday, May 29, for the Memorial Day holiday. Week 23 (Jun 5-11) * Ahead has eight tracks during the week, all at 720 kbps, and overall coverage is nominal. * The DSN mission network will be undergoing maintenance between 13:30-20:30 UT (9:30 AM to 4:30 PM, EDT) on Thursday, Jun 8. There are no STEREO passes during this period. Week 24 (Jun 12-18) * Ahead has nine tracks during the week, all at 720 kbps, and overall coverage is nominal. * The 157th momentum dump is scheduled for Tuesday, Jun 13, with ignition at 20:00 UT. * The Parker Solar Probe perihelion pass runs from Jun 17-27 (days 168-178). Week 25 (Jun 19-25) * Ahead has ten tracks during the week, all at 720 kbps, and overall coverage is nominal. Week 26 (Jun 26-Jul 2) * Ahead has ten tracks during the week, all at 720 kbps, and overall coverage is nominal. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 21: M May 22 (142) T May 23 (143) W May 24 (144) T May 25 (145) Ahead: Return-to-service track with station 43 F May 26 (146) S May 27 (147) S May 28 (148) ------------------------------------------------------------------------------- Scheduled activities for Week 22: M May 29 (149) Memorial Day T May 30 (150) W May 31 (151) T Jun 01 (152) F Jun 02 (153) S Jun 03 (154) S Jun 04 (155) ------------------------------------------------------------------------------- Scheduled activities for Week 23: M Jun 05 (156) T Jun 06 (157) W Jun 07 (158) T Jun 08 (159) F Jun 09 (160) S Jun 10 (161) S Jun 11 (162) ------------------------------------------------------------------------------- Scheduled activities for Week 24: M Jun 12 (163) T Jun 13 (164) Ahead: Momentum dump, 20:00 UT W Jun 14 (165) T Jun 15 (166) F Jun 16 (167) S Jun 17 (168) Start of Parker Solar Probe perihelion pass S Jun 18 (169) Notes: * Parker Solar Probe perihelion pass, Jun 17-27. ------------------------------------------------------------------------------- Scheduled activities for Week 25: M Jun 19 (170) T Jun 20 (171) Ahead: COR2 deep field W Jun 21 (172) Ahead: COR2 deep field T Jun 22 (173) Ahead: COR2 deep field F Jun 23 (174) Ahead: COR2 deep field S Jun 24 (175) S Jun 25 (176) Notes: * Parker Solar Probe perihelion pass, Jun 17-27. ------------------------------------------------------------------------------- Scheduled activities for Week 26: M Jun 26 (177) T Jun 27 (178) End of Parker Solar Probe perihelion pass Solar Orbiter Mercury transit W Jun 28 (179) T Jun 29 (180) F Jun 30 (181) S Jul 01 (182) S Jul 02 (183) Behind: Closest approach to Earth Notes: * Parker Solar Probe perihelion pass, Jun 17-27. ------------------------------------------------------------------------------- Upcoming events: 2023: * Jul 3-Aug 2 Ahead: SECCHI high telemetry campaign * Aug 17 Ahead: Closest approach to Earth * Aug 21 Parker Solar Probe Venus flyby * Sep 23-Oct 3 Parker Solar Probe perihelion pass * Oct 1-10 Solar Orbiter Remote Sensing Window 10 * Oct 12-21 Solar Orbiter Remote Sensing Window 11 * Oct 23-Nov 1 Solar Orbiter Remote Sensing Window 12 * Nov 13 Solar Orbiter Full Disk Mosaic * Dec 25-Jan 3 Parker Solar Probe perihelion pass * Dec 28 Solar Orbiter off-point for Parker Solar Probe 2024: * Mar 13-24 Solar Orbiter Remote Sensing Window 13 * Mar 26-Apr 4 Parker Solar Probe perihelion pass * Mar 27-Apr 9 Solar Orbiter Remote Sensing Window 14 * Apr 12-15 Solar Orbiter Remote Sensing Window 15 * Jun 26-Jul 5 Parker Solar Probe perihelion pass * Sep 26-Oct 5 Parker Solar Probe perihelion pass * Nov 6 Parker Solar Probe Venus flyby, in HI2-A field-of-view * Dec 20-29 Parker Solar Probe perihelion pass 2025: * Feb 18 Solar Orbiter Venus flyby * Mar 19-27 Parker Solar Probe perihelion pass * Apr 7 Ahead: Mercury transit * Jun 15-24 Parker Solar Probe perihelion pass 2026: * Dec 24 Solar Orbiter Venus flyby 2028: * Mar 18 Solar Orbiter Venus flyby 2029: * Jun 10 Solar Orbiter Venus flyby * Jun 30 Ahead: Mercury transit 2030: * Sep 3 Solar Orbiter Venus flyby