STEREO Weekly Meeting Minutes for 2026-01-27 (Week 5) 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 4 (Jan 19-25) * On day 020 (Jan 20), during the DSS-26 support, the MOC telemetry was lost between 12:29 and 12:31 UT, due to a DSN DCD software error. This anomaly resulted in the loss of two minutes of real-time telemetry and SSR data. The MOPs team repositioned the SSR pointers during the support and recovered all the affected data. See DR #N113793 for more information. * On day 020 (Jan 20), the MOPs team discovered that several STEREO Data Sever (SDS) text products had an invalid spacecraft time value. The problem was caused by a signed 32-bit integer clock rollover on January 19, 2026, when calculating seconds since January 1, 1958. The MOC software was corrected and the MOPs team has reprocessed the Data Products for DOY 019-021. * On day 021 (Jan 21), during the DSS-65 support, the SLE telemetry bind failed on the primary workstation, which delayed beginning of track two hours until 06:15 UT. Also, the turbo decoder lock was lost intermittently between 06:51 and 06:54 UT, due to rain. This anomaly resulted in the loss of 2077 frames of SSR data. The MOPs team repositioned the SSR pointers during the subsequent DSS-25 support and recovered all the affected data. See DR #M118753 for more information. * On day 022, (Jan 22), during the DSS-65 support, turbo decoder lock was lost briefly at 04:37 UT. Also, the MOC telemetry was lost at 07:41 and 08:05 UT, due to an emergency software update at the Madrid complex. This anomaly resulted in the loss of two minutes of realtime telemetry and SSR data. The MOPs team repositioned the SSR pointers during the subsequent DSS-56 support and recovered all the affected data. See DR #N113815 for more information. * On day 023 (Jan 23), during the DSS-56 support, turbo decoder lock was lost briefly at 07:58 UT. This anomaly resulted in the loss of 17 frames of SSR data. The MOPs team repositioned the SSR pointers during the support and recovered all the affected data. * The average daily science data return for Ahead was 7.3 Gbits during this week. Week 5 (Jan 26 - Feb 1) * Ahead has fifteen passes during the week, all at 720 kbps, and overall coverage is nominal. * There was an issue with station 65 late last night, where the antenna was declared red. The team was able to move to DSS-54 and add a DSS-24 pass early this morning to maintain communication. Thank you Alex! Week 6 (Feb 2-8) * Ahead has fourteen passes during the week, all at 720 kbps, and overall coverage is nominal. * The 78th SECCHI stepped calibration roll is scheduled for Monday, February 2nd, at 07:35 UT. * The Artemis II launch opportunity window opens on Friday, February 6th and end on February 11th. Launch-related activities at DSN have resulted in track modifications for STEREO in week 6 and week 7. Week 7 (Feb 9-15) * Ahead has twelve passes during the week, all at 720 kbps, and overall coverage is nominal. * The 183rd momentum dump is scheduled for Wednesday, February 11th. Due to a track modification, the momentum dump has been moved to 14:30 UT. * The 25th Solar Orbiter remote sensing window begins Thursday, February 12th. Week 8 (Feb 16-22) * Ahead has fifteen passes during the week, fourteen at 720 kbps, and one ESA support at 480 kbps. Overall coverage is nominal. * On Tuesday, February 17th, an ESA New Norcia track is scheduled from 18:05 to 18:55 UT. This track will be at 480 kbps, and it is planned to use this rate for all ESA support tracks going forward. Owen will monitor the distrubution of DSN and ESA tracks to ensure that all data continues to be collected with the new, lower ESA downlink rate. Week 9 (Feb 23 - Mar 1) * Ahead has thirteen passes during the week, all at 720 kbps, and overall coverage is nominal. * The 26th Solar Orbiter remote sensing window begins Saturday, February 28th. Week 10 (Mar 2-8) * Ahead has thirteen passes during the week, all at 720 kbps, and overall coverage is nominal. Other COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 05: M Jan 26 (026) T Jan 27 (027) W Jan 28 (028) T Jan 29 (029) F Jan 30 (030) S Jan 31 (031) S Feb 01 (032) ------------------------------------------------------------------------------- Scheduled activities for Week 06: M Feb 02 (033) Ahead: SECCHI stepped calibration roll, 07:35 T Feb 03 (034) W Feb 04 (035) T Feb 05 (036) F Feb 06 (037) Artemis Launch window opens S Feb 07 (038) S Feb 08 (039) Notes: * Artemis II launch window: Feb 6-11 ------------------------------------------------------------------------------- Scheduled activities for Week 07: M Feb 09 (040) T Feb 10 (041) W Feb 11 (042) Ahead: Momentum dump, 14:30 UT T Feb 12 (043) SolO RSW 25 begins F Feb 13 (044) S Feb 14 (045) S Feb 15 (046) Notes: * Artemis II launch window: Feb 6-11 * Solar Orbiter Remote Sensing Window 25, Feb 12-27 ------------------------------------------------------------------------------- Scheduled activities for Week 08: M Feb 16 (047) T Feb 17 (048) W Feb 18 (049) T Feb 19 (050) F Feb 20 (051) S Feb 21 (052) S Feb 22 (053) Notes: * Solar Orbiter Remote Sensing Window 25, Feb 12-27 ------------------------------------------------------------------------------- Scheduled activities for Week 09: M Feb 23 (054) T Feb 24 (055) W Feb 25 (056) T Feb 26 (057) F Feb 27 (058) SolO RSW 25 ends S Feb 28 (059) SolO RSW 26 begins S Mar 01 (060) Notes: * Solar Orbiter Remote Sensing Window 25, Feb 12-27 * Solar Orbiter Remote Sensing Window 26, Feb 28 - Mar 10 ------------------------------------------------------------------------------- Scheduled activities for Week 10: M Mar 02 (061) T Mar 03 (062) W Mar 04 (063) T Mar 05 (064) F Mar 06 (065) Artemis II launch window begins S Mar 07 (066) S Mar 08 (067) Start of PSP perihelion pass Notes: * Solar Orbiter Remote Sensing Window 26, Feb 28 - Mar 10 * Artemis II launch window, Mar 6-11 * Parker Solar Probe Perihelion pass, Mar 8-16 ------------------------------------------------------------------------------- Upcoming events: 2026: * Mar 29-Apr 3 Solar Orbiter Remote Sensing Window 27 * Apr 1-6 Artemis II launch window * Jun 4-12 Parker Solar Probe perihelion pass * Aug 4-14 Solar Orbiter Remote Sensing Window 28 * Aug 15-25 Solar Orbiter Remote Sensing Window 29 * Sep 1-9 Parker Solar Probe perihelion pass * Sep 11-21 Solar Orbiter Remote Sensing Window 30 * Nov 28-Dec 6 Parker Solar Probe perihelion pass * 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 ######################################################################## Access the STEREO-SCI-OPS Home Page and Archives: http://listserv.jhuapl.edu/scripts/wa.exe?A0=STEREO-SCI-OPS Unsubscribe from the STEREO-SCI-OPS List: http://listserv.jhuapl.edu/scripts/wa.exe?TICKET=NzM5NjAzIHNoYWVsYS5pLmpvbmVzbWVjaG9sc2t5QE5BU0EuR09WIFNURVJFTy1TQ0ktT1BTIGvQ3MCEIhMC&c=SIGNOFF ########################################################################