STEREO Weekly Meeting Minutes for 2010-08-10 (Week 32) ANNOUNCEMENTS ------------- * The Ahead schedule for week 35 has been modified to include two PIT tests. The dates are different than what was reported last week. See below for details. * The network at APL will be upgraded on Saturday, Sep 11, from 12:00-13:30 UT. The MOC will be unreachable via email or pagers during this time, but cell phones will still work. Spacecraft operations will be unaffected. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 31 * The station 15 transmitter was red at the beginning of the Ahead track on day 218 (Aug 6) due to a transmitter motor generator anomaly. The transmitter was brought up late in the track at 15:47 UT, and a command was sent. However, a coolant problem at 15:52 caused the transmitter to be disabled again for the rest of the track. A small amount of SSR data for all instruments was lost during the uplink sweep. * Turbo decoder lock was lost briefly at 05:40 UT and again at 07:34 UT during the station 34 pass for Behind on day 218 (Aug 6). This resulted in the loss of 5 frames of SECCHI data. * The 14th SECCHI stepped calibration roll was carried out on Behind on day 215 (Aug 3), starting at 14:00 UT. This was the midpoint roll. * The average daily SSR downlink was 5.1 gigabits for Ahead, and 4.9 gigabits for Behind. Week 32 * The 14th SECCHI stepped calibration roll on Ahead was carried out early this morning (Aug 10) starting at 08:10 UT. This was the midpoint roll. * Track coverage during the week will be about 4.7 hours above nominal for Ahead, and 1.8 hours above nominal for Behind, with good spacing. Week 33 * There are a number of tracks on Ahead during the week, but many of them are short. No spacecraft telemetry will be downloaded during short Ahead tracks on Monday, Tuesday, and Friday. * Ahead will have a 70 meter track on day 231, Thursday, Aug 19, using station 63 in Madrid. This track will be carried out at 720 kbps and last 3 hrs. No spacecraft telemetry will be downloaded during this tracks. * Behind will have a 70 meter track on Saturday, Aug 21 using station 43 in Canberra. This track will be carried out at 720 kbps and last just over 6 hours * Spacecraft telemetry will not be read out during a short track on Behind on Friday, day 232 (Aug 20), starting at 21 UT. * Overall track coverage for Ahead is 4.7 hours above nominal during the week. For Behind it is 3.1 hours below nominal, but no in situ data are expected to be lost. Week 34 * Ahead will have a 70 meter track on Thurs. Aug 26 using station 63 in Madrid. This track will be carried out at 720 kbps and will last 3 hrs. No spacecraft telemetry will be read out during this track. * No spacecraft telemetry will be read out during a short track for Ahead on Monday, Aug 23. * Behind will have a 70 meter track on Sunday Aug 29 using station 43 in Canberra. This track will be carried out at 720 kbps. Track duration is about 7 hours. * Overall track coverage during the week is 1.4 hours above nominal for Ahead, and 3.3 hours above nominal for Behind. Week 35 * Momentum dump #32 for Ahead during the week is scheduled for Aug 31, starting at 13:30 UT. * There will be a 70 meter track for Ahead on day 243 (Aug 31), and again on day 246 (Sep 3), and a 70 meter track for Behind on day 244 (Sep 1), all using station 63 in Madrid. These tracks will be carried out at 720 kbps. No spacecraft telemetry will be read out during the Ahead track on day 246 (Sep 3). * Track coverage for Ahead is 3.8 hours above nominal, while track coverage for Behind is even. Week 36 * Ahead and Behind were originally scheduled to go to 8 hour track schedules this week, but that has now been pushed back to spring or summer of next year. * A Project Interface Test (PIT) has been scheduled for Ahead on Wednesday, day 251 (Sep 8) to test a new interface. A second PIT test is scheduled on Friday, day 253 (Sep 10). (Note: these dates are different from what was reported last week.) No SSR data will be downloaded during these tests, and no POC commanding will be performed. No in situ data should be lost because of these tests. Because there is a lot of coverage during the week, SECCHI data volume shouldn't be affected. * There are a number of 70 meter stations scheduled during the week. These tracks will be carried out at 720 kbps. 70 meter tracks for Ahead occur on days 249 (Sep 6), 252 (Sep 9) and 255 (Sep 12), all using station 63 in Madrid. Behind has 70 meter tracks on day 250 (Sep 7) using station 43 in Canberra, and on day 253 (Sep 10) using station 63 in Madrid. * The network at APL will be upgraded on Saturday, Sep 11, from 12:00-13:30 UT. The MOC will be unreachable via email or pagers during this time, but cell phones will still work. Spacecraft operations will be unaffected. * The 26th momentum dump on Behind will be carried out on day 250 (Sep 7), starting at 22:30 UT, during an 8 hour pass. * Overall coverage during the week for Ahead is 7.8 hours above nominal, and 4.2 hours above nominal for Behind. * Monday is the Labor Day holiday. Week 37 * Ahead has 720 kbps passes using station 63 on Monday, day 256 (Sep 13), Wednesday, day 258 (Sep 15), and Saturday, day 261 (Sep 18). * Behind has a 720 kbps pass on day 256 (Sep 13) using station 63. No spacecraft telemetry will be downlinked during this pass. * Overall coverage for the week is 6.6 hours over nominal for Ahead, and 7 hours over nominal for Behind. Week 38 * Ahead will have 720 kbps passes using station 63 on Tuesday, day 264 (Sep 21), and Friday, day 267 (Sep 24). There will be another 720 kbps on day 267 (Sep 24) using station 43. * Behind will have a 720 kbps pass on Wednesday, day 265 (Sep 22) using station 63 in Madrid. * Overall coverage is 7.8 hours over nominal for Ahead, and 7 hours over nominal for Behind. * There will be a return-to-service track for station 65 on Behind on Sep 23, shadowing the station 54 track at the same time. Other * There are a number of mission events during 2011-2012 which will cause a lot of contention for DSN time. This period starts when Messenger will have an orbital insertion around Mercury in March, 2011. Dawn will rendezvous with Vesta sometime in the summer of 2011. Several missions will be launched in 2011, including JUNO and GRAIL. GRAIL is asking for a lot of track time. They have a 9 month mission, which will have a hard end in June 2012 when the spacecraft start going into eclipse. Because of all these activities, in particular GRAIL, the period is more contentious than usual. The DSN is looking into options to try to mitigate this situation. * The DSN contentions during this period will be partially mitigated for the STEREO in situ instruments because their telemetry rates will drop when the spacraft go to 160 kbps and later 120 kbps. IMPACT also has some strategies to handle low telemetry volume periods. The other in situ instrument teams should consider what mitigation strategies are available to them when telemetry coverage is low. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 32: M Aug 09 (221) T Aug 10 (222) Ahead: SECCHI stepped calibration roll, 08:10 UT W Aug 11 (223) T Aug 12 (224) F Aug 13 (225) S Aug 14 (226) S Aug 15 (227) ------------------------------------------------------------------------------- Scheduled activities for Week 33: M Aug 16 (228) T Aug 17 (229) W Aug 18 (230) T Aug 19 (231) Ahead: 720 kbps downlink on station 63 F Aug 20 (232) S Aug 21 (233) Behind: 720 kbps downlink on station 43 S Aug 22 (234) ------------------------------------------------------------------------------- Scheduled activities for Week 34: M Aug 23 (235) T Aug 24 (236) W Aug 25 (237) T Aug 26 (238) Ahead: 720 kbps downlink on station 63 F Aug 27 (239) S Aug 28 (240) S Aug 29 (241) Behind: 720 kbps downlink on station 43 ------------------------------------------------------------------------------- Scheduled activities for Week 35: M Aug 30 (242) T Aug 31 (243) Ahead: 720 kbps downlink on station 63 Ahead: Momentum dump, 13:30 UT W Sep 01 (244) Behind: 720 kbps downlink on station 63 T Sep 02 (245) F Sep 03 (246) Ahead: 720 kbps downlink on station 63 S Sep 04 (247) S Sep 05 (248) ------------------------------------------------------------------------------- Scheduled activities for Week 36: M Sep 06 (249) Ahead: 720 kbps downlink on station 63 T Sep 07 (250) Behind: 720 kbps downlink on station 43 Behind: Momentum dump, 22:30 UT W Sep 08 (251) Ahead: PIT test T Sep 09 (252) Ahead: 720 kbps downlink on station 63 F Sep 10 (253) Behind: 720 kbps downlink on station 63 Ahead: PIT test S Sep 11 (254) S Sep 12 (255) Ahead: 720 kbps downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 37: M Sep 13 (256) Ahead: 720 kbps downlink on station 63 Behind: 720 kbps downlink on station 63 T Sep 14 (257) W Sep 15 (258) Ahead: 720 kbps downlink on station 63 T Sep 16 (259) F Sep 17 (260) S Sep 18 (261) Ahead: 720 kbps downlink on station 63 S Sep 19 (262) ------------------------------------------------------------------------------- Scheduled activities for Week 38: M Sep 20 (263) T Sep 21 (264) Ahead: 720 kbps downlink on station 63 W Sep 22 (265) Behind: 720 kbps downlink on station 63 T Sep 23 (266) Behind: Return-to-service track for station 65 F Sep 24 (267) Ahead: 720 kbps downlink on station 63, and on station 43 S Sep 25 (268) S Sep 26 (269) ------------------------------------------------------------------------------- Upcoming events: 2010: SECCHI Stepped calibration rolls Ahead: Nov 2 Behind: Oct 12 2011: * Spring/Summer Ahead: End use of 720 kbps on 70 m DSN subnet * Spring/Summer Behind: End use of 720 kbps on 70 m DSN subnet * Jan 12 Both: HGA calibration * Feb 6 STEREO spacecraft at 180 degree separation * Mar Behind: Switch downlink rate to 160 kbps * Mar 18 Messenger - Mercury orbital insertion * Jul DAWN - Vesta arrival * Jul 13 Both: HGA calibration 2012: * Jan 11 Both: HGA calibration * Jun Ahead: Switch downlink rate to 160 kbps * Jul DAWN - Vesta departure * Jul 11 Both: HGA calibration * Nov 13 Total solar eclipse, south Pacific 2013: * Dec 12 Ahead: Mercury transit 2014: * Apr 29 Behind: Mercury transit 2015: * Feb DAWN - Ceres arrival * Jan 10 - Apr 12 (TBC) Behind: Spacecraft behind Sun * Feb 17 - Aug 2 (TBC) Ahead: Spacecraft behind Sun * Jul 23 - Nov 10 (TBC) Behind: Spacecraft behind Sun * Jul DAWN - End of nominal mission 2016: 2017: 2018: * Mar 5 Ahead: Mercury transit