STEREO Weekly Meeting Minutes for 2020-07-28 (Week 31) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * Ahead is operating nominally. PLASTIC is back to operational mode, but with a higher 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 30 (Jul 20-26) * On day 206 (Jul 24), during the DSS-14 support for Ahead, the transmitter was declared red due to a power supply problem. This anomaly resulted in the loss of 1.7 hours of real-time commanding and 2-way tracking data. See DR #G121245 for more information. * On day 207 (Jul 25), during the DSS-63 support for Ahead, turbo decoder lock was lost intermittently from 1305z through 1307z. This anomaly resulted in the loss of 5297 frames of SSR data. On the subsequent DSS-14 support, MOPs repositioned the SSR pointers and recovered all the affected DSS-63 data. See DR #M112448 for more information. * On day 208 (Jul 26), during the DSS-63 support for Ahead, the transmitter was declared red due to a wave-guide cooling problem. This anomaly resulted in the loss of 1.8 hours of real-time commanding and 2-way tracking data. See DR #M112453 for more information. * On day 202 (Jul 20), the SECCHI 180 degree roll was executed successfully on Ahead at 1200z for the third Betelgeuse star observation. An Astronomer's Telegram announcing the results will be released soon. * On day 204 (Jul 22), the SECCHI instrument on Ahead reset at 23:51:44z. The SECCHI team reconfigured the instrument to operational mode by 205-0041z. This was the 63rd reset of the SECCHI instrument on the Ahead observatory. * On day 205 (Jul 23), the ninth battery discharge event was conducted successfully at 2049z on the Ahead spacecraft to redistribute the electrolytes within the nickel hydrogen battery cells. * As of day 208 (Jul 26), 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 6.7 Gbits during this week. 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 took place yesterday, Jul 27, between 8-10 UT. An additional roll has been added on Aug 3. Week 32 (Aug 3-9) * Ahead has sixteen passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, two at 480 kbps, and six at 360 kbps. The station 14 pass on Sunday, Aug 9, was shortened, and a station 54 pass just before that was added to assist another mission. * An additional 180 degree roll to observe Betelgeuse has been scheduled for Monday, Aug 3, between 16-18 UT, upon request from the Harvard Smithsonian Center for Astrophysics. This will be the final roll, as Betelgeuse will no longer be observable after Aug 5. * 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. Week 34 (Aug 17-23) * Ahead has eleven passes during the week, and overall coverage is nominal. There are five passes at 720 kbps, three at 480 kbps, and three at 360 kbps. Week 35 (Aug 24-30) * Ahead has thirteen passes during the week, and overall coverage is nominal. There are seven passes at 720 kbps, one at 480 kbps, four at 360 kbps, and one at 240 kbps. Week 36 (Aug 31-Sep 6) * Ahead has fourteen passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, three at 480 kbps, and three at 360 kbps. Week 37 (Sep 7-13) * Ahead has ten passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, three at 480 kbps, and one at 360 kbps. * Monday, Sep 7, is Labor Day, which is an APL holiday. * An ESA New Norcia pass is scheduled for Thursday, Sep 10, from 08:05-10:45 UT. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- 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) Ahead: 180 degree roll for observation of Betelgeuse, 16-18 UT 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) ------------------------------------------------------------------------------- Scheduled activities for Week 34: M Aug 17 (230) T Aug 18 (231) W Aug 19 (232) T Aug 20 (233) F Aug 21 (234) S Aug 22 (235) S Aug 23 (236) ------------------------------------------------------------------------------- Scheduled activities for Week 35: M Aug 24 (237) T Aug 25 (238) W Aug 26 (239) T Aug 27 (240) F Aug 28 (241) S Aug 29 (242) S Aug 30 (243) ------------------------------------------------------------------------------- Scheduled activities for Week 36: M Aug 31 (244) T Sep 01 (245) W Sep 02 (246) T Sep 03 (247) F Sep 04 (248) S Sep 05 (249) S Sep 06 (250) ------------------------------------------------------------------------------- Scheduled activities for Week 37: M Sep 07 (251) Labor Day T Sep 08 (252) W Sep 09 (253) T Sep 10 (254) F Sep 11 (255) S Sep 12 (256) S Sep 13 (257) ------------------------------------------------------------------------------- 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