STEREO Weekly Meeting Minutes for 2020-07-07 (Week 28) 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 27 (Jun 29-Jul 5) * On day 184 (Jul 2), during the DSS-63 support for Ahead, the station lost connections and communication with all subsystems, which delayed commanding by 23 minutes and the 2-way downlink mode acquisition by four minutes. Also, turbo decoder lock was lost briefly at 1944z. These anomalies resulted in the loss of seven minutes of real-time telemetry and SSR data. On the subsequent DSS-25 support, MOPs repositioned the SSR pointers and all affected DSS-63 data was recovered. See DR #M112407 for more information. * On day 181 (Jun 29), the 129th momentum dump on Ahead was executed successfully on Ahead at 1500z, which imparted an estimated delta V of 0.076 m/sec. This was the 48th momentum dump conducted without gyro use. After thruster operations completed, there was a 0.4 degree of roll angle error. Fine pointing stabilized 3.5 minutes after completion of the momentum dump. * As of day 187 (Jul 5), all PLASTIC systems on Ahead are behaving well, except there is a high background count rate, which the team is continuing to monitor. * The average daily science data return for Ahead was 6.6 Gbits during this week. * PLASTIC delivered new software to the SSC for processing their beacon data. That software has been put in place. Also, the SSC has reprocessed all the PLASTIC beacon data back to April 9, when a change was made to the onboard calculation of moments which the new software depends on. Density and velocity measurements have improved, but the background is currently too high to allow temperature to be measured. * PLASTIC Level 1 data are in raw units, and don't require reprocessing. The team is still working on producing Level 2 data. These may be available soon, and will probably be able to be produced for earlier than April 9, since they don't depend on onboard moments. * The PLASTIC background has been declining, but sometimes suddenly jumps up for unknown reasons, after which it starts to decline again. These jumps often happen around two days after momentum dumps and other activities. The team is continuing to analyze the background behavior. Week 28 (Jul 6-12) * Ahead has ten passes during the week, and overall coverage is nominal. There are seven passes at 720 kbps, two at 480 kbps, and one at 360 kbps. * The period from days 185-194 (Jul 3-12) is reserved for SECCHI HI observations in support of the Parker Solar Probe Venus fly-by. Week 29 (Jul 13-19) * Ahead has nine passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, one at 480 kbps, and two at 360 kbps. * The second 180 degree roll to observe Betelgeuse is scheduled for Monday, Jul 13, between 20-22 UT. * The 54th SECCHI stepped calibration roll is scheduled for Wednesday, Jul 15, starting at 16:35 UT. This is the midpoint roll. Week 30 (Jul 20-26) * Ahead has twelve passes during the week, and overall coverage is nominal. There are seven passes at 720 kbps, two at 480 kbps, and three at 360 kbps. * An ESA New Norcia pass is scheduled for Thursday, Jul 23, 06:00-8:30 UT. * The third 180 degree roll to observe Betelgeuse is scheduled for Monday, Jul.20, between 12-14 UT. Week 31 (Jul 27-Aug 2) * Ahead has eleven passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, and five at 480 kbps. * The fourth 180 degree roll to observe Betelgeuse is scheduled for Monday, Jul 27, between 8-10 UT. Week 32 (Aug 3-9) * Ahead has fifteen passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, two at 480 kbps, and five at 360 kbps. * An ESA New Norcia pass is scheduled for Thursday, Aug 6, 08:30-12:30. * A test of the three links per operator link test is scheduled for Friday, Aug 7, using station 14. There will be no instrument commanding or SSR downlink during this pass. Week 33 (Aug 10-16) * Ahead has thirteen passes during the week, and overall coverage is nominal. There are ten passes at 720 kbps, one at 480 kbps, and two at 360 kbps. * The 130th momentum dump on Ahead is scheduled for Tuesday, Aug 11, with ignition at 21:00 UT. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 28: M Jul 06 (188) T Jul 07 (189) W Jul 08 (190) T Jul 09 (191) F Jul 10 (192) S Jul 11 (193) Parker Solar Probe Venus flyby, in HI2-A field-of-view S Jul 12 (194) Notes: * SECCHI HI observations for Parker Solar Probe, Jul 3-12 ------------------------------------------------------------------------------- Scheduled activities for Week 29: M Jul 13 (195) Ahead: 180 degree roll for observation of Betelgeuse, 20-22 UT T Jul 14 (196) W Jul 15 (197) Ahead: SECCHI stepped calibration roll, 16:35 UT T Jul 16 (198) F Jul 17 (199) S Jul 18 (200) S Jul 19 (201) ------------------------------------------------------------------------------- Scheduled activities for Week 30: M Jul 20 (202) Ahead: 180 degree roll for observation of Betelgeuse, 12-14 UT T Jul 21 (203) W Jul 22 (204) T Jul 23 (205) F Jul 24 (206) S Jul 25 (207) S Jul 26 (208) ------------------------------------------------------------------------------- Scheduled activities for Week 31: M Jul 27 (209) Ahead: 180 degree roll for observation of Betelgeuse, 8-10 UT T Jul 28 (210) W Jul 29 (211) T Jul 30 (212) F Jul 31 (213) S Aug 01 (214) S Aug 02 (215) ------------------------------------------------------------------------------- Scheduled activities for Week 32: M Aug 03 (216) T Aug 04 (217) W Aug 05 (218) T Aug 06 (219) F Aug 07 (220) Ahead: 3 links/operator link test with station 14 S Aug 08 (221) S Aug 09 (222) ------------------------------------------------------------------------------- Scheduled activities for Week 33: M Aug 10 (223) T Aug 11 (224) Ahead: Momentum dump, 21:00 UT W Aug 12 (225) T Aug 13 (226) F Aug 14 (227) S Aug 15 (228) S Aug 16 (229) ------------------------------------------------------------------------------- Upcoming events: Behind events are contingent on recovering the spacecraft. 2020: * 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 * 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