STEREO Weekly Meeting Minutes for 2020-04-21 (Week 17) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * Ahead is operating nominally. PLASTIC is back to operational mode, but with a higher background rate. More time is needed to understand the new calibraton. * 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 16 (Apr 13-19) * On day 106 (Apr 15), during the DSS-65 support for Ahead, initial acquisition of telemetry and commanding were 15 minutes late at 1840z, due to rain. On the subsequent DSS-14 support, MOPs repositioned the SSR pointers and all affected DSS-65 SSR data was recovered. See DR #M112206 for more information. * On day 110 (Apr 19), during the DSS-63 support for Ahead, the antenna was declared red due to a power outage caused by weather. This anomaly resulted in the loss of 2.3 hours of real-time telemetry, commanding and tracking data. On the subsequent DSS-14 support, MOPs repositioned the SSR pointers and all affected DSS-63 SSR data was recovered. See DR # M112219 for more information. * On day 106 (Apr 15), the SECCHI instrument reset at 07:28:54z. The SECCHI team reconfigured the instrument to operational mode by 1923z. This was the 61st reset of the SECCHI instrument on the Ahead observatory. * As of day 110, all PLASTIC systems are behaving well, except there is a high background count rate, which the team is continuing to monitor. The PLASTIC team reports that they are in the midst of working with the algorithms for the space weather beacon data. They are changing the parameters they use for the beacon data. The new software is not ready yet. * The average daily science data return for Ahead was 6.9 Gbits during this week. Week 17 (Apr 20-26) * Ahead has fifteen passes during the week, and overall coverage is nominal. There are eleven passes at 720 kbps, one at 480 kbps, and three at 360 kbps. Because there were back-to-back station 63 passes at the end of the week, a station 26 pass was added out of caution, to make sure that the command loss timer would not trigger. * On Monday, Apr 20, Madrid suffered a power failure which rendered the station 63 transmitter red. Commands were sent up on the following station 25 pass, so there was no impact. * The 53rd SECCHI stepped calibration roll is scheduled for Wednesday, Apr 22, starting at 13:50 UT. This is the aphelion roll. * A four hour internet outage at APL is scheduled between 8 AM and 12 noon on Sunday, Apr 26. Instrument teams will need to reconnect after this activity. Week 18 (Apr 27-May 3) * Ahead has thirteen passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, and five at 360 kbps. To assist another mission, the 480 kbps station 54 pass on Friday, May 1, was changed to a 360 kbps support with station 65. * Solar Orbiter will be along the Sun-Earth line between Apr 27 to May 3. The SECCHI team has requested that spacecraft operations be avoided during this period. Solar Orbiter resumed commissioning activities on Monday, Mar 30. Week 19 (May 4-10) * Ahead has sixteen passes during the week, and overall coverage is nominal. There are eleven passes at 720 kbps, and five at 360 kbps. Week 20 (May 11-17) * Ahead has thirteen passes during the week, and overall coverage is nominal. There are eleven passes at 720 kbps, and two at 360 kbps. Week 21 (May 18-24) * Ahead has seventeen passes during the week, and overall coverage is nominal. There are twelve passes at 720 kbps, one at 480 kbps, and four at 360 kbps. * The 128th momentum dump on Ahead is scheduled for Monday, May 18, with ignition at 18:00 UT. Week 22 (May 25-31) * Ahead has eleven passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, and three at 360 kbps. * Monday, May 25, is Memorial Day. Other * The MOC wishes to express their thanks to Madrid for all the effort taken to keep the antennas up, considering the restrictions due to the coronavirus. The station 63 receiver was back into operation by Sunday, and the transmitter was back to green this morning. * DSN has a workaround for the recent problems with Turbo decoder lock by implementing some commands during setup. However, because of the minimal staffing during the coronavirus situation, this option can only be used during critical passes. DSN is working on automating this new procedure. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 17: M Apr 20 (111) T Apr 21 (112) W Apr 22 (113) Ahead: SECCHI stepped calibration roll, 13:50 UT T Apr 23 (114) F Apr 24 (115) S Apr 25 (116) S Apr 26 (117) ------------------------------------------------------------------------------- Scheduled activities for Week 18: M Apr 27 (118) T Apr 28 (119) W Apr 29 (120) T Apr 30 (121) F May 01 (122) S May 02 (123) S May 03 (124) Notes: * Apr 27-May 3 Solar Orbiter along Sun-Earth line ------------------------------------------------------------------------------- Scheduled activities for Week 19: M May 04 (125) T May 05 (126) W May 06 (127) T May 07 (128) F May 08 (129) S May 09 (130) S May 10 (131) ------------------------------------------------------------------------------- Scheduled activities for Week 20: M May 11 (132) T May 12 (133) W May 13 (134) T May 14 (135) F May 15 (136) S May 16 (137) S May 17 (138) ------------------------------------------------------------------------------- Scheduled activities for Week 21: M May 18 (139) Ahead: Momentum dump, 18:00 UT T May 19 (140) W May 20 (141) T May 21 (142) F May 22 (143) S May 23 (144) S May 24 (145) ------------------------------------------------------------------------------- Scheduled activities for Week 22: M May 25 (146) Memorial Day T May 26 (147) W May 27 (148) T May 28 (149) F May 29 (150) S May 30 (151) S May 31 (152) ------------------------------------------------------------------------------- Upcoming events: Behind events are contingent on recovering the spacecraft. 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 * 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