STEREO Weekly Meeting Minutes for 2015-07-28 (Week 31) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * Ahead is back to normal operations on the second side lobe. * There are currently no communications with the Behind spacecraft. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 30 (Jul 20-26) * On day 201 (Jul 20), during the DSS-14 support for Ahead, turbo decoder lock was lost intermittently between 1408z and 1926z due to the effects of solar scintillation. This anomaly resulted in the loss of 17 frames of spacecraft SSR playback and real-time data. * On day 202 (Jul 21), during the DSS-45 support for Ahead, turbo decoder lock was lost intermittently between 2227z and 203-0116z due to the effects of solar scintillation. This anomaly resulted in the loss of 18 frames of spacecraft SSR playback and real-time data. * On day 202, during the DSS-14 support, turbo decoder lock was lost briefly at 0413z due to the effects of solar scintillation. This anomaly resulted in the loss of one frame of real-time data. * On day 203, during the DSS-55 support, turbo decoder lock was lost intermittently between 1133z and 1140z due to the effects of solar scintillation. This anomaly resulted in the loss of 23 frames of spacecraft SSR playback and real-time data. * On day 206, during the DSS-14 support, turbo decoder lock was lost intermittently between 2052z and 207-0056z due to the effects of solar scintillation. This anomaly resulted in the loss of 10 frames of spacecraft SSR playback and real-time data. * There were no lost commands during the week. * On July 20th, day 201, PLASTIC completed configuring from solar conjunction and returned to science mode, so now all instruments are once again returning science for side lobe operations. * The Ahead observatory is operating nominally on the 2nd side lobe of the HGA to prevent overheating of the HGA feed assembly which is currently at 110 degrees C and decreasing with the HGA angle at 8.9 degrees and increasing, with respect to the spacecraft-Sun line. * On day 202 (Jul 21), the G&C routine SSR partition (#9) read pointer was re-positioned back to the pre-solar conjunction value, day 083, March 24th. The read pointer was moved on day 191, July 10th, to retrieve the data faster from anomalies that occurred during solar conjunction. * On day 204 (Jul 23), the 78th momentum dump was executed successfully at 2100z, which imparted a delta V of 0.068 m/sec. IMU2 was used for 1.1 hours and the momentum target was set to the nominal 15 Nms. * SECCHI noticed that some of their packets were missing right after the momentum dump. There was some discussion about the difference between queue overflows and lost telemetry frames. * Behind started the week at an SPE angle of 3.1 degrees. There were no passes for Behind during the week. Week 31 (Jul 27-Aug 2) * There have been no lost commands for Ahead so far during the week. * Ahead starts the week at an SPE angle of 2.8 degrees, on the second side lobe. * Ahead has 18 tracks during the week, with eight 70 meter tracks at 3 kbps, and ten 34 meter tracks at 633 bps. Total space weather coverage is 59%. * Behind starts the week at an SPE angle of 2.9 degrees. There will be no passes for Behind during the week. Behind reaches perihelion on Aug 2. Week 32 (Aug 3-9) * Ahead starts the week at an SPE angle of 3.1 degrees, on the second side lobe. * Ahead has 19 tracks during the week. It is short 8.1 hours of 70 meter time, mostly between Monday to Wednesday, due to critical events for the Juno mission, but there are 70 meter tracks every day. Ten tracks are with 34 meter stations, resulting in 55% space weather coverage during the week. * Behind starts the week at an SPE angle of 2.7 degrees. There will be no passes for Behind during the week. Week 33 (Aug 10-16) * There will be a project interface test (PIT) using station 35 on Monday, Aug 10, between 03:45 and 6:40 UT. There will be no instrument commanding or SSR playback during this track. * Ahead has 17 tracks during the week, nine using 70 meter stations at 3 kbps, and eight using 34 meter stations at 633 bps, giving an overall space weather coverage of 55%. * There is a return-to-service track for station 63 on Wednesday, Aug 12. There will be no commanding or SSR playback during this track. * Ahead starts the week at an SPE angle of 3.3 degrees, on the second side lobe. This will be the last week on the second side lobe. * Ahead will shift to the 1st side lobe near the end of the third 70 meter track (station 14) on Sunday, Aug 16. There will be a 34 meter support following this shift using station 35, though still at 633 bps. * Behind starts the week at an SPE angle of 2.5 degrees. There will be no passes for Behind during the week. Week 34 (Aug 17-23) * Ahead starts the week at an SPE angle of 3.6 degrees, on the first side lobe. Alternating weeks of IMPACT-prime and SWAVES-prime will resume, starting with IMPACT being prime. * Ahead has 14 passes during the week, with seven passes at 10 kbps, and 7 passes at 633 bps, with overall space weather coverage of 31%. * Behind starts the week at an SPE angle of 2.4 degrees. There will be no passes for Behind during the week. Week 35 (Aug 24-30) * Ahead starts the week at an SPE angle of 3.9 degrees, on the first side lobe, with SWAVES being prime. * Ahead has 19 passes during the week, with seven passes at 10 kbps, and twelve passes at 633 bps, with overall space weather coverage of 39%. * Behind starts the week at an SPE angle of 2.2 degrees. There will be no passes for Behind during the week. Week 36 (Aug 31-Sep 6) * Ahead starts the week at an SPE angle of 4.1 degrees, on the first side lobe, with IMPACT being prime. * Ahead has 17 passes during the week, with eight passes at 10 kbps, and nine passes at 633 bps, with overall space weather coverage of 35%. * Behind starts the week at an SPE angle of 2.1 degrees. There will be no passes for Behind during the week. Week 37 (Sep 7-13) * Ahead starts the week at an SPE angle of 4.3 degrees, on the first side lobe, with SWAVES being prime. * Ahead has 14 passes during the week, with seven passes at 10 kbps, and seven passes at 633 bps. * APL will be closed on Monday, Sep 7, for the Labor Day holiday. Other * The IMPACT team was asked when the SIT tables would be loaded. The current thinking is to wait until the spacecraft is back on the first side lobe. * A question was asked about the possibility of doing calibration rolls without using the IMU. The MOC is still looking into this possibility. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 31: M Jul 27 (208) T Jul 28 (209) W Jul 29 (210) T Jul 30 (211) F Jul 31 (212) S Aug 01 (213) S Aug 02 (214) Notes: * Ahead operating on second side lobe. * No tracks for Behind due to superior solar conjunction. ------------------------------------------------------------------------------- Scheduled activities for Week 32: M Aug 03 (215) T Aug 04 (216) W Aug 05 (217) T Aug 06 (218) F Aug 07 (219) S Aug 08 (220) S Aug 09 (221) Notes: * Ahead operating on second side lobe. * No tracks for Behind due to superior solar conjunction. ------------------------------------------------------------------------------- Scheduled activities for Week 33: M Aug 10 (222) Ahead: Project interface test with station 35 T Aug 11 (223) W Aug 12 (224) Ahead: Return-to-service track with station 63 T Aug 13 (225) F Aug 14 (226) S Aug 15 (227) S Aug 16 (228) Ahead: Switch to first side lobe. Notes: * Ahead operating on second side lobe. * No tracks for Behind due to superior solar conjunction. ------------------------------------------------------------------------------- Scheduled activities for Week 34: M Aug 17 (229) T Aug 18 (230) W Aug 19 (231) T Aug 20 (232) F Aug 21 (233) S Aug 22 (234) S Aug 23 (235) Notes: * Ahead operating on the first side lobe, in IMPACT-prime mode. * No tracks for Behind due to superior solar conjunction. ------------------------------------------------------------------------------- Scheduled activities for Week 35: M Aug 24 (236) T Aug 25 (237) W Aug 26 (238) T Aug 27 (239) F Aug 28 (240) S Aug 29 (241) S Aug 30 (242) Notes: * Ahead operating on the first side lobe, in SWAVES-prime mode. * No tracks for Behind due to superior solar conjunction. ------------------------------------------------------------------------------- Scheduled activities for Week 36: M Aug 31 (243) T Sep 01 (244) W Sep 02 (245) T Sep 03 (246) F Sep 04 (247) S Sep 05 (248) S Sep 06 (249) Notes: * Ahead operating on the first side lobe, in IMPACT-prime mode. * No tracks for Behind due to superior solar conjunction. ------------------------------------------------------------------------------- Scheduled activities for Week 37: M Sep 07 (250) Labor Day T Sep 08 (251) W Sep 09 (252) T Sep 10 (253) F Sep 11 (254) S Sep 12 (255) S Sep 13 (256) Notes: * Ahead operating on the first side lobe, in SWAVES-prime mode. * No tracks for Behind due to superior solar conjunction. ------------------------------------------------------------------------------- Upcoming events: Behind events are contingent on recovering the spacecraft. 2015: * Nov 10 Ahead: HGA on main lobe, offpoint 1 degree, 240 kbps Ahead: SSR playback and reconfiguration, S/C checkout Ahead: Resume space weather broadcast to NOAA stations * Nov 12 Ahead: Instrument recommissioning * Nov 16 Ahead: HGA on main lobe, offpoint 1 degree, 360 kbps Behind: Resume Behind recovery efforts * Nov 20 Behind: HGA on 1st side lobe * Nov 30 Ahead: HGA on main lobe, offpoint 1 degree, 480 kbps * Dec 30 Ahead: HGA on main lobe 2016: * Jan 2 Behind: HGA on main lobe, offpoint 1 degree Behind: SSR playback and reconfiguration, S/C checkout * Jan 5 Behind: Instrument recommissioning * Jan 12 Behind: HGA on main lobe * Jan 27 Both: HGA calibration * Mar 16 Both: Post Solar Conjunction Assessment Review * Jul 5 Juno arrival at Jupiter 2017: * Jul 11 Ahead: Switch downlink rate to 160 kbps * Jul 22 Behind: Switch downlink rate to 160 kbps 2018: * Mar 5 Ahead: Mercury transit 2019: * Mar Ahead: Switch downlink rate to 240 kbps * Apr Behind: Switch downlink rate to 240 kbps 2020: * May Behind: Switch downlink rate to 360 kbps * Jun Ahead: Switch downlink rate to 360 kbps * Jun Behind: Switch downlink rate to 480 kbps * Sep Ahead: Switch downlink rate to 480 kbps 2021: * Jul Behind: Switch downlink rate to 720 kbps * Aug Ahead: Switch downlink rate to 720 kbps