STEREO Weekly Meeting Minutes for 2020-01-07 (Week 2) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * Ahead is operating nominally. PLASTIC is in the process of returning to nominal operations after suffering a voltage anomaly on Dec 5. See more information below. * 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 51 (Dec 16-22) * On day 353 (Dec 19), during the DSS-24 support for Ahead, the downlink receiver failed to lock at BOT, due to a software problem. The station added another downlink receiver at 0105z. This anomaly resulted in loss of real-time telemetry between 0100z and 0105z, including the loss of three minutes of SSR data. See DR #G120758 for more information. * On day 355 (Dec 21), during the DSS-14 support for Ahead, the station lost link connection, resulting in the uplink services being delayed by ten minutes. This anomaly resulted in the loss of two minutes of real-time and SSR data. See DR #G120768 for more information. DSN reports that there is no update on the Java problem. * On day 354 (Dec 20), The PLASTIC instrument encountered another problem during their reset recovery. The instrument team was unable to command high voltages due error flags in the IMPACT DPU. The team was unable to clear the flags, and the only course of action was to Power cycle the instrument and restart the recovery process over. * On day 355 (Dec 21), the SECCHI instrument reset at 00:06:41z. The SECCHI team reconfigured the instrument to operational mode by 355-0222z. This was the 57th reset of the SECCHI instrument on the Ahead observatory. * On day 355 (Dec 21), the PLASTIC instrument was Powered cycled at 0157z and the error flags in the IMPACT DPU were cleared successfully. The Post Acceleration (PAC) Power Supply high voltage was stepped to -5kV and the PLASTIC team reported the PAC was nominal. The PLASTIC team will continue to monitor the PAC temperatures and currents, and they will start to gradually ramp up the high voltages on Monday (Dec 23). * The average daily science data return for Ahead was 6.2 Gbits during this week. Week 52 (Dec 23-29) * On day 358 (Dec 24), during the DSS-34 support for Ahead, turbo decoder lock was lost intermittently from 0406z through 0851z. This anomaly resulted in the loss of 36 frames of SSR data. * On day 359 (Dec 25), during the DSS-63 support for Ahead, the station lost link connection from 1457z through 1506z, resulting in the 2-way downlink acquisition being nine minutes late. This anomaly resulted in loss of real-time telemetry between 1457z and 1506z, including the loss of six minutes of SSR data. See DR #M111949 for more information. * On day 360 (Dec 26), during the DSS-34 support for Ahead, turbo decoder lock was lost intermittently from 0851z through 1028z. This anomaly resulted in the loss of 12 frames of SSR data. * On day 361 (Dec 27), during the DSS-14 support for Ahead, the station lost link connection from 0111z through 0120z, resulting in the 2-way downlink acquisition being nine minutes late. This anomaly resulted in loss of real-time telemetry between 0111z and 0120z, including the loss of six minutes of SSR data. See DR #G120780 for more information. * On day 363 (Dec 29), during the DSS-14 support for Ahead, monitor data stopped updating between 0111z and 0145z, due to a link connection problem. This anomaly had no operational impact. See DR# G120787 for more information. * On day 358 (Dec 24), The PLASTIC team continued to monitor the Post Acceleration (PAC) Power Supply temperatures and currents as they reconfigured the instrument to recovery from the HV anomaly. They began to gradually ramp up the high voltages. * On day 358 (Dec 24), the SECCHI instrument reset at 12:18:11z. The SECCHI team reconfigured the instrument to operational mode by 359-0150z. This was the 58th reset of the SECCHI instrument on the Ahead observatory. * On day 363 (Dec 29), the PLASTIC team commanded through different one hour diagnostic modes. The current working hypothesis, for which they are running diagnostic time-tag commands to confirm or not, is that PLASTIC was struck by a dust impact, and a remnant of this dust particle made it to entrance plane of the carbon foil. The carbon foil entrance plane is held at the PAC voltage. In this (hypothetical) scenario, when the PAC HV is on, the high voltage potential is ionizing volatiles from the remnant. This increases the load on the PAC power supply, and hence the increase in PAC current draw. The higher the PAC voltage, the higher the ionization, and the higher the current. This also causes high rates being measured by the instrument detectors. The good news is that the rates (and PAC current) appear to decline (very) slowly over time, which they interpret as the volatiles dissipating at a given PAC voltage value. All other power supplies (MCP, SSD, SCH, ESA, DEFL1 and DEFL2) have been engaged at full operational settings with no issues. The PLASTIC team anticipate several more days before returning to a science operational state. * The average daily science data return for Ahead was 6.2 Gbits during this week. Week 01 (Dec 30-Jan 5) * On day 365 (Dec 31), during the DSS-14 support for Ahead, SLE telemetry binds were dropped at 2020-001-000000z, due a software problem at the year rollover. This anomaly resulted in the loss of 3.7 hours of MOC real-time telemetry monitoring. The issue was resolved and the SLE TLM binds were re-established prior to the next support. See DR #N111315 for more information. * On day 365 (Dec 31), during the DSS-14 support for Ahead, the ranging system hung at 2020-001-0000z through 001-0029z. The system reported values of zero due a software problem at the year rollover. This anomaly resulted in the loss of 29 minutes of ranging data. See DR #G120792 for more information. * On day 002 (Jan 2), during the DSS-14 support for Ahead, monitor data stopped updating between 0111z and 0150z, due to a link connection problem. This anomaly had no operational impact. See DR #G120794 for more information. * On day 003 (Jan 3), during the DSS-14 support for Ahead, the ranging system modulation was delayed until 0113z, due to a link connection problem. This anomaly resulted in the loss of two minutes of ranging data. See DR #G120799 for more information. * On day 005 (Jan 5), the PLASTIC team is continuing to monitor the rates and Post Acceleration (PAC) Power Supply current, which continue to decline slowly over time. * The PLASTIC team reported that they are unsure when the instrument will be back to normal operating mode, but they do not expect it to be this week. * The average daily science data return for Ahead was 7.0 Gbits during this week. Week 02 (Jan 6-12) * Ahead has fourteen passes during the week, and overall coverage is nominal. There are nine passes at 720 kbps, four at 360 kbps, and one at 160 kbps. Week 03 (Jan 13-19) * Ahead has fifteen passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, one at 480 kbps, four at 360 kbps, and two at 160 kbps. * The 51st SECCHI stepped calibration roll on Ahead is scheduled for Tuesday, Jan 14, starting at 13:00 UT. * The 125th momentum dump on Ahead is scheduled for Thursday, Jan 16, with ignition at 19:30 UT. Week 04 (Jan 20-26) * Ahead has eleven passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, one at 480 kbps, and two at 360 kbps. * The Parker Solar Probe perihelion pass is from Jan 24 to Feb 4. Week 05 (Jan 24-Feb 2) * Ahead has thirteen passes during the week, and overall coverage is nominal. There are ten passes at 720 kbps, and three at 360 kbps. * The Parker Solar Probe perihelion pass is from Jan 24 to Feb 4. Week 06 (Feb 3-9) * Ahead has twelve passes during the week, and overall coverage is nominal. There are eight passes at 720 bps, one at 480 kbps, and three at 360 kbps. * The Parker Solar Probe perihelion pass is from Jan 24 to Feb 4. Week 07 (Feb 10-16) * Ahead has twelve passes during the week, and overall coverage is nominal. There are ten passes at 720 kbps, one at 360 kbps, and one at 160 kbps. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 02: M Jan 06 (006) T Jan 07 (007) W Jan 08 (008) T Jan 09 (009) F Jan 10 (010) S Jan 11 (011) S Jan 12 (012) Notes: * PLASTIC in the process of being recovered to normal operations after power cycling. ------------------------------------------------------------------------------- Scheduled activities for Week 03: M Jan 13 (013) T Jan 14 (014) Ahead: SECCHI stepped calibration roll, 13:00 W Jan 15 (015) T Jan 16 (016) Ahead: Momentum dump, 19:30 UT F Jan 17 (017) S Jan 18 (018) S Jan 19 (019) ------------------------------------------------------------------------------- Scheduled activities for Week 04: M Jan 20 (020) T Jan 21 (021) Ahead: COR2 deep field campaign with Parker Solar Probe W Jan 22 (022) Ahead: COR2 deep field campaign with Parker Solar Probe T Jan 23 (023) Ahead: COR2 deep field campaign with Parker Solar Probe F Jan 24 (024) Start of Parker Solar Probe perihelion pass S Jan 25 (025) S Jan 26 (026) Notes: * Parker Solar Probe perihelion pass, Jan 24-Feb 4. ------------------------------------------------------------------------------- Scheduled activities for Week 05: M Jan 27 (027) T Jan 28 (028) W Jan 29 (029) T Jan 30 (030) F Jan 31 (031) S Feb 01 (032) S Feb 02 (033) Notes: * Parker Solar Probe perihelion pass, Jan 24-Feb 4. ------------------------------------------------------------------------------- Scheduled activities for Week 06: M Feb 03 (034) T Feb 04 (035) End of Parker Solar Probe perihelion pass. W Feb 05 (036) T Feb 06 (037) F Feb 07 (038) S Feb 08 (039) S Feb 09 (040) Notes: * Parker Solar Probe perihelion pass, Jan 24-Feb 4. ------------------------------------------------------------------------------- Scheduled activities for Week 07: M Feb 10 (041) T Feb 11 (042) W Feb 12 (043) T Feb 13 (044) F Feb 14 (045) S Feb 15 (046) S Feb 16 (047) ------------------------------------------------------------------------------- Upcoming events: Behind events are contingent on recovering the spacecraft. 2020: * Apr 27-May 3 Solar Orbiter along Sun-Earth line (TBC after launch) * 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 * Jul 11 Parker Solar Probe Venus flyby, in HI2-A field-of-view * 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 * Feb 20 Parker Solar Probe Venus flyby * 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 * Oct 16 Parker Solar Probe Venus flyby * 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 * Aug 21 Parker Solar Probe Venus flyby * 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 * Nov 6 Parker Solar Probe Venus flyby, in HI2-A field-of-view * 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