STEREO Weekly Meeting Minutes for 2013-07-02 (Week 27) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 26 (Jun 24-30) * On day 175 (Jun 24), during the DSS-65 support for Ahead, telemetry was received five minutes late at 0445z due to low signal power caused by a sub-reflector problem. Also during the track, turbo decoder lock was lost briefly at 0551z. These anomalies resulted in the loss of three minutes (1062 frames) of SSR data. See DR #M107376 for more information. * On day 176 (Jun 25), during the DSS-26 support for Ahead, turbo decoder lock was lost briefly at 1237z. This anomaly resulted in the loss of one frame of SSR data. The new DR request procedure is now being followed, and a DR was not requested for this anomaly. * On day 176 (Jun 25), during the DSS-25 support for Behind, the OPS Chief called for permission to perform a DCD failover at 1955z because the FDS was not transmitting IDR files during the previous DSS-26 support for Ahead. The IDR files for the track were FTP'd manually and level-0 data was reprocessed for day 175 for both spacecraft as version number 05. All SSR data were recovered. See DR #N108979 for more information. * On day 177 (Jun 26), the MOC external connectivity was offline for remote users between 2100z-2200z due to an APL firewall upgrade. * On day 181 (Jun 30), during the DSS-63 support for Ahead, the receiver and ranging processor unexpectedly went out of lock between 1146z-1148z. Also during this track, turbo decoder lock was lost intermittently beginning at 0746z through 1234z. These anomalies resulted in the loss of 5598 frames of SSR data. See DRs #M107387 and #M107386 respectively for more information. * On day 175 (Jun 24), during the DSS-45 support for Behind, turbo decoder lock was lost intermittently beginning at 0326z through 0327z. This anomaly resulted in the loss of 23 frames of SSR data. See DR #N108969 for more information. * On day 177 (Jun 26), during the DSS-54 support for Behind, turbo decoder lock was lost briefly at 1051z and again at 1059z. This anomaly resulted in the loss of eight frames of SSR data. * On day 178 (Jun 27), during the DSS-63 support for Behind, turbo decoder lock was lost briefly at 1332z and again at 1340z. This anomaly resulted in the loss of 27 frames of SSR data. * On day 180 (Jun 29), during the DSS-63 support for Behind, the receiver and ranging processor unexpectedly went out of lock between 1138z-1141z. Also during this track, turbo decoder lock was lost intermittently beginning at 1027z through 1405z. These anomalies resulted in the loss of 4453 frames of SSR data. See DRs #M107383 for more information. * On day 181 (Jun 30), during the DSS-63 support for Behind, the receiver and ranging processor unexpectedly went out of lock between 1406z-1408z, 1419z-1420z, 1616z-1617z, and 1656z-1657z. Also during this track, turbo decoder lock was lost intermittently beginning at 1403z through 1725z. These anomalies resulted in the loss of 12753 frames of SSR data. See DRs #M107389 for more information. * The question was raised whether the recent problems with the station 63 receiver would be addressed during the upcoming downtime for the station. It's not currrently on the task list. However, DSN is investigating the problem with the station 63 receiver. It was also asked what was the current link margin for the 70 meter stations, but this would need to be looked into. * The average daily SSR playback volume during the week was 4.2 gigabits for Ahead, and 4.8 gigabits for Behind. Week 27 (Jul 1-7) * The 58th momentum dump for Ahead was carried out successfully yesterday (Jul 1). * The station 15 antenna was red for the Behind pass last night (Jul 1). The passed was switched to station 14, and carried out successfully. The SSR pointers were moved back, and no data were lost. * A return-to-service track for station 24 is scheduled with the Ahead spacecraft on Wednesday, Jul 3. There will be no SSR downlink or instrument commanding during this track. * Jul 4 is Independence Day, which is a holiday at APL. * Ahead has 9 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Friday, Jul 5, and Sunday, Jul 7, both using station 63 at 720 kbps. The following passes will be carried out at 160 kbps: Monday, Jul 1 (D26), and Thursday, Jul 4 (D15). * Behind has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jul 1 (D43), Wednesday, Jul 3 (D63 at 720 kbps), Friday, Jul 5 (D14 at 720 kbps), Saturday, Jul 6 (D63 at 720 kbps), and Sunday, Jul 7 (D63 at 720 kbps). Week 28 (Jul 8-14) * The modified autonomy rul 239 for the SSR pointer moves, to avoid the long track issue that has been recently experienced, will be uploaded to both spacecraft on Monday, Jul 8. * IMPACT will perform realtime commanding for the HET instrument on the Ahead spacecraft on Monday, Jul 8. This is the same change that was recently applied to Behind. * Additional engineering demos using attenuators with the STEREO beacon broadcast on Behind are scheduled for Monday, Jul 8 (D24), Tuesday, Jul 9 (D55), and Saturday, Jul 13 (D65). * The 18th HGA calibrations are scheduled for the Ahead spacecraft on Tuesday, Jul 9, at 17:00 UT, and for the Behind spacecraft on Wednesday, Jul 10, at 16:00 UT. * A return-to-service track for station 55 with the Ahead spacecraft is scheduled for Wednesday, Jul 10. There will be no SSR downlink or instrument commanding during this track. * The 53rd momentum dump on Behind is scheduled for Thursday, Jul 11, with ignition at 17:00 UT. * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jul 8, Wednesday, Jul 10, Thursday, Jul 11, and Friday, Jul 12, all using station 14. The station 15 pass on Saturday, Jul 13, will be carried out at 160 kbps. * Behind has 9 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jul 8 (D63 at 720 kbps), Tuesday, Jul 9 (D63 at 720 kbps), and Saturday, Jul 13 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Saturday, Jul 13 (D65), and Sunday, Jul 14 (D24). Week 29 (Jul 15-21) * Additional engineering demos using attenuators with the STEREO beacon broadcast on Behind are scheduled for Monday, Jul 15 (D25), and Wednesday, Jul 17 (D34). * Ahead has 8 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jul 15 (D14), Wednesday, Jul 17 (D14), Thursday, Jul 18 (D43, D14), Friday, Jul 19 (D43), Saturday, Jul 20 (D14), and Sunday, Jul 21 (D14). * Behind has 12 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jul 15 (D43), and Wednesday, Jul 17 (D43, D14 at 720 kbps). The following passes will be carried out at 160 kbps: Saturday, Jul 20 (D54, D24). Week 30 (Jul 22-28) * A Project Interface Test will be carried out on station 26 with Behind on Wednesday, Jul 24, to test uplink software. There will be no SSR playback or instrument commanding during this test. * Ahead has 10 tracks during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Jul 23 (D14), Wednesday, Jul 24 (D43), Thursday, Jul 25 (D14), and Saturday, Jul 27 (D14 at 720 kbps). The station 26 pass on Sunday, Jul 28, will be carried out at 240 kbps. * Behind has 14 passes during the week, and overall coverage is nominal. A 70 meter pass is scheduled for Thursday, Jul 25 (D43 at 720 kbps). The station 26 pass on Saturday, Jul 27, will be carried out at 240 kbps. The following passes will be carried out at 160 kbps: Monday, Jul 22 (D26), Friday, Jul 26 (D26 twice), and Sunday, Jul 28 (D54). Week 31 (Jul 29-Aug 4) * Ahead has 9 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Jul 29 (D14), Tuesday, Jul 30 (D14), Thursday, Aug 1 (D14), and Friday, Aug 2 (D14, D43). The following passes will be carried out at 160 kbps: Wednesday, Jul 31 (D54), and Saturday, Aug 3 (D54, D25). * Behind has 10 passes during the week, and overall coverage is nominal. A 70 meter pass is scheduled for Tuesday, Jul 30 (D14 at 720 kbps). The following passes will be carried out at 160 kbps: Tuesday, Jul 30 (D55), and Sunday, Aug 4 (D55). Week 32 (Aug 5-11) * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Aug 6 (D14), Wednesday, Aug 7 (D14), and Sunday, Aug 11 (D63). The following passes will be carried out at 160 kbps: Thursday, Aug 8 (D54) and Saturday, Aug 10 (D45). * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Thursday, Aug 8 (D14), and Sunday, Aug 11 (D63 at 720 kbps). The station 26 pass on Wednesday, Aug 7, will be carried out at 160 kbps. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 27: M Jul 01 (182) Ahead: Momentum dump, 16:00 UT T Jul 02 (183) W Jul 03 (184) Ahead: Return-to-service track for station 24 T Jul 04 (185) Independence Day F Jul 05 (186) S Jul 06 (187) S Jul 07 (188) ------------------------------------------------------------------------------- Scheduled activities for Week 28: M Jul 08 (189) Behind: Engineering demo with station 24 T Jul 09 (190) Ahead: HGA calibration, 17:00 Behind: Engineering demo with station 55 W Jul 10 (191) Ahead: Return-to-service track for station 55 Behind: HGA calibration, 16:00 T Jul 11 (192) Behind: Momentum dump, 17:00 F Jul 12 (193) S Jul 13 (194) Behind: Engineering demo with station 65 S Jul 14 (195) ------------------------------------------------------------------------------- Scheduled activities for Week 29: M Jul 15 (196) Behind: Engineering demo with station 25 T Jul 16 (197) W Jul 17 (198) Behind: Engineering demo with station 34 T Jul 18 (199) F Jul 19 (200) S Jul 20 (201) S Jul 21 (202) ------------------------------------------------------------------------------- Scheduled activities for Week 30: M Jul 22 (203) T Jul 23 (204) W Jul 24 (205) Behind: PIT test with station 26 T Jul 25 (206) F Jul 26 (207) S Jul 27 (208) S Jul 28 (209) ------------------------------------------------------------------------------- Scheduled activities for Week 31: M Jul 29 (210) T Jul 30 (211) W Jul 31 (212) T Aug 01 (213) F Aug 02 (214) S Aug 03 (215) S Aug 04 (216) ------------------------------------------------------------------------------- Scheduled activities for Week 32: M Aug 05 (217) T Aug 06 (218) W Aug 07 (219) T Aug 08 (220) F Aug 09 (221) S Aug 10 (222) S Aug 11 (223) ------------------------------------------------------------------------------- Upcoming events: 2013: * Nov 28 Both: Perihelion passage of Comet ISON http://stereo-ssc.nascom.nasa.gov/comet_ison/ * Dec 12 Ahead: Mercury transit 2014: * Jan 20 Behind: End use of 480 kbps on 70 m DSN subnet * Apr 21 Behind: Resume use of 480 kbps on 70 m DSN subnet * Apr 29 Behind: Mercury transit * Sep 07-Nov 15 Behind: Passage of Comet Siding Spring through HI2-B * Oct 15 Behind: End use of 480 kbps on 70 m DSN subnet * Oct 17 Behind: Comet Siding Spring encounter with Mars 2015: * Feb DAWN - Ceres arrival * Jan 20 - Mar 28 (TBC) Behind: Spacecraft behind Sun * Mar 17 - Jul 14 (TBC) Ahead: Spacecraft behind Sun * Jul 2 Behind: Resume use of 480 kbps on 70 m DSN subnet * Aug 25 - Oct 19 (TBC) Behind: Spacecraft behind Sun * Sep 25 Behind: End use of 480 kbps on 70 m DSN subnet * Jul DAWN - End of nominal mission 2016: * Apr 3 Behind: Resume use of 480 kbps on 70 m DSN subnet * Jul 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