STEREO Weekly Meeting Minutes for 2026-05-12 (Week 20) 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 19 (May 4-10) * On day 125 (May 5), the DSS-43 Emergency Control Center (ECC) test was conducted successfully with the MOC and FDF. The purpose was to validate telemetry, commanding, monitor data (MON-0158), tracking data, and voice comms through the ECC. The MOC was able to perform SLE Telemetry Binds with the ECC servers and Command Binds with DSS-43. The MOC received real-time telemetry, monitor data, and sent 14 commands via all three MOC command/telemetry machines. The MOC successfully performed voice comms with the DSS-43 and ECC. The FDF successfully retrieved the tracking data and uploaded the ephemeris file to the ECC SPS portal. * On day 125 (May 5), during the DSS-55 support, the SECCHI SSR Partition 19 reached 100% full for 3.9 hours from 00:39 to 04:33 UT. The partition filling was caused by the lost DSS-55 support on DOY 124, due to maintenance for hardware repairs. * On day 126 (May 6), during the DSS-63 support, the SECCHI SSR Partition 19 reached 100% full for 1.8 hours from 02:28 to 04:18 UT. The partition filling was caused by the lost DSS-55 support on DOY 124, due to maintenance for hardware repairs. * On day 126 (May 6), during the DSS-63 support, turbo decoder lock was lost briefly at 05:14 UT. This anomaly resulted in the loss of five frames of SSR data. The MOPs team repositioned the SSR pointers during the support and recovered all the affected data. * On day 126 (May 6), the 185th momentum dump was executed successfully at 13:30 UT, which imparted an estimated delta V of 0.076 m/sec. This was the 104th momentum dump conducted without gyro use. After thruster operations completed, there was a 0.6 degree of roll angle error. Fine pointing stabilized 2.5 minutes after completion of the momentum dump. * On day 127 (May 7), during the DSS-25 support, turbo decoder lock was lost briefly at 11:46 UT. This anomaly resulted in the loss of six frames of SSR data. The MOPs team repositioned the SSR pointers during the support and recovered all the affected data. * On day 130 (May 10), during the DSS-63 support, turbo decoder lock was lost briefly at 11:46 UT. This anomaly resulted in the loss of 87 frames of SSR data. The MOPs team repositioned the SSR pointers during the support and recovered all the affected data. See DR #M119112 for more information. * On day 130 (May 10), during the DSS-25 support, the transmitter tripped offline at 19:44 UT. This anomaly resulted in the loss of 31 minutes of commanding, 2-way tracking, and the loss of 2223 frames of SSR data. MOPs team repositioned the SSR pointers during the support and recovered all the affected data. See DR #G126026 for more information. * The average daily science data return for Ahead was 7.0 Gbits during this week. Week 20 (May 11-17) * Ahead has fifteen passes during the week, two at 720 kbps and thirteen at 480 kbps, and overall coverage is nominal. * There was a DSN network maintenance event conducted on Monday, May 11th, from 15:00 to 19:00 UT with no issues. * The 20th battery discharge event will take place today, Tuesday, May 12th at 17:40 UT. * On Thursday, May 14th, a MOC IONET secutiry scan is scheduled from 18:30 to 22:30 UT. Week 21 (May 18-24) * Ahead has thirteen passes during the week, one at 720 kbps and twelve at 480 kbps, and overall coverage is nominal. * The 79th SECCHI stepped calibration roll is scheduled for Tuesday, May 19th, at 22:10 UT. This is the perihelion roll. * Commercial power at APL will be down for maintenance between 06:00 UT on day 143, to 21:00 UT on day 144, i.e. between 2 AM Saturday to 5 PM Sunday local time. The MOC will be operating on generators during this time. Week 22 (May 25-31) * Ahead has thirteen passes during the week, three at 720 kbps and ten at 480 kbps, and overall coverage is nominal. * APL will be closed on Monday, May 25, for the Memorial Day holiday. * A NASCOM network maintenance event is scheduled for Tuesday, May 26, between 17:30 and 20:30 UT. Week 23 (June 1-7) * Ahead has twelve passes during the week, one at 720 kbps and eleven at 480 kbps, and overall coverage is nominal. * There is a Parker Solar Probe perihelion pass scheduled June 4th through 12th. Week 24 (June 8-14) * Ahead has twelve passes during the week, four at 720 kbps, and eight at 480 kbps. * There is a DSN network maintenance event scheduled for Monday, June 8th, from 00:00 - 04:00 UT (8-12pm local time). * The 186th momentum dump is scheduled for Thursday, June 11th, at 13:40 UT. Week 25 (June 15-21) * Ahead has fourteen passes during the week, two at 720 kbps, and twelve at 480 kbps. Other * None COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 20: M May 11 (131) T May 12 (132) W May 13 (133) T May 14 (134) F May 15 (135) S May 16 (136) S May 17 (137) ------------------------------------------------------------------------------- Scheduled activities for Week 21: M May 18 (138) T May 19 (139) Ahead: SECCHI stepped calibration roll, 22:10 UT W May 20 (140) T May 21 (141) F May 22 (142) S May 23 (143) S May 24 (144) ------------------------------------------------------------------------------- Scheduled activities for Week 22: M May 25 (145) Memorial Day holiday T May 26 (146) W May 27 (147) T May 28 (148) F May 29 (149) S May 30 (150) S May 31 (151) ------------------------------------------------------------------------------- Scheduled activities for Week 23: M Jun 01 (152) T Jun 02 (153) W Jun 03 (154) T Jun 04 (155) Start of PSP perihelion pass F Jun 05 (156) S Jun 06 (157) S Jun 07 (158) Notes: * Parker Solar Probe perihelion pass, Jun 4-12 ------------------------------------------------------------------------------- Scheduled activities for Week 24: M Jun 08 (159) T Jun 09 (160) W Jun 10 (161) T Jun 11 (162) Ahead: Momentum dump, 13:40 F Jun 12 (163) End of PSP perihelion pass S Jun 13 (164) S Jun 14 (165) Notes: * Parker Solar Probe perihelion pass, Jun 4-12 ------------------------------------------------------------------------------- Scheduled activities for Week 25: M Jun 15 (166) T Jun 16 (167) W Jun 17 (168) T Jun 18 (169) F Jun 19 (170) S Jun 20 (171) S Jun 21 (172) ------------------------------------------------------------------------------- Upcoming events: 2026: * 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 2027: * Feb 25-Mar 4 Parker Solar Probe perihelion pass * Feb 8 Solar Orbiter Perihelion * May 24-31 Parker Solar Probe perihelion pass * July 7 Solar Orbiter Perihelion * Aug 21-28 Parer Solar Probe perihelion pass * Nov 17-24 Parker Solar Probe perihelion pass * Dec 4 Solar Orbiter Perihelion 2028: * Feb 14-21 Parker Solar Probe perihelion pass * Mar 18 Solar Orbiter Venus flyby * May 8 Solar Orbiter Perihelion * May 12-19 Parker Solar Probe perihelion pass * Aug 8-15 Parker Solar Probe perihelion pass * Oct 5 Solar Orbiter Perihelion * Nov 5-12 Parker Solar Probe perihelion pass 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=NzM5NzcxIHNoYWVsYS5pLmpvbmVzbWVjaG9sc2t5QE5BU0EuR09WIFNURVJFTy1TQ0ktT1BTIMG0K%2Bb5AcPP&c=SIGNOFF ########################################################################