STEREO Weekly Meeting Minutes for 2013-08-06 (Week 32) ANNOUNCEMENTS ------------- * The planned work on the DMZ computers has been rescheduled for Monday, Aug 26, between 20-23 UT. This will require several reboots, and instrument teams can expect to need to reconnect. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 31 (Jul 29-Aug 4) * On day 215 (Aug 3), during the DSS-54 support for Ahead, turbo decoder lock was lost briefly at 1215z. This anomaly resulted in the loss of one frame of SSR data. * On day 216 (Aug 4), during the DSS-65 support for Ahead, turbo decoder lock was lost briefly at 1139z and again at 1202z. This anomaly resulted in the loss of five frames of SSR data. * On day 211 (Jul 30) on Ahead, and on day 212 (Jul 31) on Behind, the MOPS permanent autonomy release 1.1.16 was loaded to C&DH EEPROM to modify rule 239, which moves SSR write limit pointers during SSR science playbacks to free recorder space. This modification removed the unnecessary check of "write limit not equal to read pointer", which was preventing SECCHI partition pointer moves during longer the 720Kbps tracks. * On day 211 (Jul 30), during the DSS-55 support for Behind, turbo decoder lock was lost briefly at 1449z and again at 1624z. This anomaly resulted in the loss of four frames of SSR data. * On day 212 (Jul 31), during the DSS-55 support for Behind, turbo decoder lock was lost briefly at 1557z. This anomaly resulted in the loss of one frame of SSR data. * On day 212 (Jul 31), during the DSS-14 support for Behind, turbo decoder lock was lost intermittently beginning at 213-0123z through 2130125z. This anomaly resulted in the loss of 1565 frame of SSR data. See DR #G114134 for more information. * On day 213 (Aug 1), during the DSS-55 support for Behind, turbo decoder lock was lost briefly at 1719z. This anomaly resulted in the loss of one frame of SSR data. * The average daily SSR playback volume during the week was 4.4 gigabits for Ahead, and 3.8 gigabits for Behind. Week 32 (Aug 5-11) * A return-to-service track for station 63 with the Behind spacecraft is scheduled for Tuesday, Aug 6. This track will be shadowing the station 55 track. * The 59th momentum dump on Ahead will be carried out at 16:30 UT on Wednesday, Aug 7. * The 54th momentum dump on Behind will be carried out at 17:00 UT on Wednesday, Aug 7. * SWAVES will be performing a flight software load on Behind on Tuesday, Aug 6, and will reboot to the new software version on Thursday, Aug 8. Backup dates for these activities are Wednesday, Aug 7, and Friday, Aug 9, respectively. Most of the SWAVES flight software load is actually expected to take place during the Wednesday pass. This is the same flight software change that was made on Ahead some time ago. This new software will be needed by the Behind spacecraft in mid-August. * 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. Week 33 (Aug 12-18) * An engineering demo using attenuators with the STEREO beacon broadcast on Behind is scheduled for Tuesday, Aug 13 (D45). * The station 25 pass for Behind on Tuesday, Aug 13, will be downlink only. * Ahead has 11 passes during the week, and overall coverage is nominal. A 70 meter pass is scheduled for Friday, Aug 16 (D14). The following passes will be carried out at 160 kbps: Tuesday, Aug 13 (D65), Saturday, Aug 17 (D65, D15), and Sunday, Aug 18 (D54). ESA New Norcia passes are scheduled for Monday and Tuesday, Aug 12, 13. * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Aug 12 (D43), Thursday, Aug 15 (D63 at 720 kbps), and Friday, Aug 16 (D14). The following passes will be carried out at 160 kbps: Monday, Aug 12 (D26), Tuesday, Aug 13 (D24), Saturday, Aug 17 (D25), and Sunday, Aug 18 (D65). Week 34 (Aug 19-25) * Ahead has 9 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Aug 20 (D14), and Thursday, Aug 22 (D43). The following passes will be carried out at 160 kbps, all using station 54: Monday, Aug 19, Saturday, Aug 24, and Sunday, Aug 25. * Behind has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Aug 19 (D43), Wednesday, Aug 21 (D63), and Thursday, Aug 22 (D14). The following passes will be carried out at 160 kbps: Tuesday, Aug 20 (D65), and Saturday, Aug 24 (D25). Week 35 (Aug 26-Sep 1) * DMZ work will be performed on Monday, Aug 26. See announcement above for details. * Ahead has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Aug 27 (D43), Friday, Aug 30 (D63), and Sunday, Sep 1 (D63). The following passes will be carried out at 160 kbps: Tuesday, Aug 27 (D54), Wednesday, Aug 28 (D55), and Thursday, Aug 29 (D54). * Behind has 8 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Aug 26 (D63), Wednesday, Aug 28 (D63), Thursday, Aug 29 (D63), and Friday, Aug 30 (D14 at 720 kbps). The station 24 pass on Sunday, Sep 1, will be carried out at 160 kbps. Week 36 (Sep 2-8) * Monday, Sep 2, is Labor 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 Monday, Sep 2 (D63), Tuesday, Sep 3 (D63), Thursday, Sep 5 (D43), Friday, Sep 6 (D63, D43), Saturday, Sep 7 (D63), and Sunday, Sep 8 (D63). * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Wednesday, Sep 4 (D63), Thursday, Sep 5 (D63, D14), Saturday, Sep 7 (D63 at 720 kbps), and Sunday, Sep 8 (D63). The following passes will be carried out at 160 kbps: Monday, Sep 2 (D45), and Friday, Sep 6 (D55, D24). Week 37 (Sep 9-15) * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Sep 9 (D14), Tuesday, Sep 10 (D63), Friday, Sep 13 (D63), and Saturday, Sep 14 (D14). The following passes will be carried out at 160 kbps: Wednesday, Sep 11 (D26), and Saturday, Sep 14 (D65). ESA New Norcia passes are scheduled for Wednesday, Sep 11, and Thursday, Sep 12. * Behind has 9 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Wednesday, Sep 11, Thursday, Sep 12, Friday, Sep 13, and Saturday, Sep 14, all using station 63. The station 45 pass on Monday, Sep 9, will be carried out at 160 kbps, and the station 26 pass on Thursday, Sep 12, will be carried out at 240 kbps. Other * The Go/No-go date for the Ahead reduced gyro operations has been slipped to Aug 20, and may slip again. * Honeywell reports that the gyro lasers can probably run at a lower intensity than thought, which gives more time. * There was some discussion about the possible use of DSN station 15 for the Comet ISON observations. Right now, return-to-service demo tracks are being scheduled for Nov 25 to Dec 6, with the actual return-to-service on Dec 20. A request has been made to bring up station 15 temporarily between Nov 25 and Dec 1 for Comet ISON observations by STEREO and SOHO, with the data not being committed, assuming that is acceptable to the instrument teams. There was some discussion whether the start of this period should be pushed forward to Nov 21. The MOC will clarify the dates. * Three upcoming launches complicate the use of DSN time: LADEE, MAVEN, MOMS. * At the Comet ISON workshop last week, there was an informal agreement that the teams trying to observe Comet ISON would share DSN time equitably. Known missions observing Comet ISON are STEREO, SOHO, MESSENGER, MAVEN, and other Mars missions. The prime time for MESSENGER is believed to be about a week earlier than perihelion passage. * The MOC will try to get the DSN priority for STEREO increased from Level 4 to Level 3 during the prime Comet ISON observing period. * The SECCHI team is still working on their proposal for roll observations. They would like to start rolls on the Behind spacecraft starting Oct 24. They discussed two possible options: either daily rolls, or rolls for ~3 days followed by a few days without rolling. Either way, they would like to do daily rolls for about two weeks around perihelion, except for the few days right at perihelion. Three different roll angles would be used for Behind: 180 degrees before perihelion, and then 290 degrees after perihelion, switching to 315 degrees later in December. They would also like to roll the Ahead spacecraft by 30 degrees for about a month after perihelion, which would be either daily, or 3 days on / 3 days off. They're also looking into whether these rolls should be 2 hours or 4 hours long. The question was raised as to whether these durations include both roll and dwell times, or only dwell times--they will look into that. They will also look back at the Comet Elenin observations to see how long the rolls took. A more detailed proposal will be released soon for comment. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 32: M Aug 05 (217) T Aug 06 (218) Behind: Return-to-service track for D63 shadowing D55 W Aug 07 (219) Momentum dump, Ahead: 16:30 UT, Behind: 17:00 UT T Aug 08 (220) F Aug 09 (221) S Aug 10 (222) S Aug 11 (223) ------------------------------------------------------------------------------- Scheduled activities for Week 33: M Aug 12 (224) T Aug 13 (225) Behind: Station 25 pass downlink only Behind: Engineering demo with station 45 W Aug 14 (226) T Aug 15 (227) F Aug 16 (228) S Aug 17 (229) S Aug 18 (230) ------------------------------------------------------------------------------- Scheduled activities for Week 34: M Aug 19 (231) T Aug 20 (232) W Aug 21 (233) T Aug 22 (234) F Aug 23 (235) S Aug 24 (236) S Aug 25 (237) ------------------------------------------------------------------------------- Scheduled activities for Week 35: M Aug 26 (238) T Aug 27 (239) W Aug 28 (240) T Aug 29 (241) F Aug 30 (242) S Aug 31 (243) S Sep 01 (244) Notes: * DMZ maintenance, Aug 26, 20-23 UT ------------------------------------------------------------------------------- Scheduled activities for Week 36: M Sep 02 (245) Labor Day T Sep 03 (246) W Sep 04 (247) T Sep 05 (248) F Sep 06 (249) S Sep 07 (250) S Sep 08 (251) ------------------------------------------------------------------------------- Scheduled activities for Week 37: M Sep 09 (252) T Sep 10 (253) W Sep 11 (254) T Sep 12 (255) F Sep 13 (256) S Sep 14 (257) S Sep 15 (258) ------------------------------------------------------------------------------- Upcoming events: 2013: * Oct 10-Nov 23 Ahead: Comet ISON in HI2 field-of-view * Nov 21-28 Ahead: Comet ISON in HI1 field-of-view * Nov 28 Both: Perihelion passage of Comet ISON http://stereo-ssc.nascom.nasa.gov/comet_ison/ * Dec 1-7 Ahead: Comet ISON in HI1 field-of-view * 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