STEREO Weekly Meeting Minutes for 2011-08-16 (Week 33) ANNOUNCEMENTS ------------- * The network upgrades at APL originally scheduled for Sep 17 have been rescheduled for sometime in November. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 32 (Aug 8-14) * On day 220 (Aug 8), during the DSS 26 support for Ahead, turbo decoder lock was lost briefly beginning at 1437z. This resulted in the loss of seven frames of SSR data. See DR# N107527 for more information. * On day 222 (Aug 10), the MOC was notified that the DSS 14 antenna would be down on days 223, 225, and 226 (Aug 11,13,14) to correct a failed master equatorial servo interface. The Ahead observatory was scheduled to use DSS 14 on days 223 and 226. A 1.4 hour replacement track with DSS 43 was used on day 223 (Aug 11) and a 4.25 hour DSS 54 replacement track was used on day 226 (Aug 14). As a result of insufficient track time, the IMPACT science partition reached capacity, resulting in the loss of 4.2 hours of science data on day 223 (Aug 11), from 0816z through 1229z, and again on day 224 (Aug 12) for a duration of 2.7 hours for IMPACT and SWAVES science partitions from 0850z through 1132z. * On day 223 (Aug 11), during the DSS 15 support for Ahead, telemetry lock was briefly lost at 1551z when the antenna stopped tracking due to a power glitch at the Goldstone complex. The antenna was reset and telemetry lock was re-acquired at 1552z. Later in the support, the turbo decoder lost lock briefly at 1617z. These anomalies resulted in the loss of several minutes of instrument SSR data. See DR# G111875 for more information. * On day 222 (Aug 10), during the DSS 24 support for Behind, turbo decoder lock was lost briefly beginning at 0139z. This resulted in the loss of one frame of SSR data. See DR# N107531 for more information. * On day 222 (Aug 10), during the DSS 54 support for Behind, a DCD anomaly occurred which failed to transmit an IDR file to the MOC. The file was retransmitted successfully on day 227 (Aug 15) and an additional version of the level zero data product for day 222 was created. * On day 223 (Aug 11), during the DSS 26 support for Behind, a DCD anomaly occurred which failed to transmit an IDR file to the MOC. The file was retransmitted successfully on day 227 (Aug 15) and an additional version of the level zero data product for day 223 was created. * On day 224 (Aug 12), during the DSS 25 support for Behind, turbo decoder lock was lost briefly beginning at 2351z. This resulted in the loss of one frame of SSR data. * On days 213 through 224 (Aug 1-12), a SECCHI HI 135 degree roll events to observe Comet Elenin was executed successfully once each day on the BEHIND observatory. Comet Elenin is now visible in HI1-B without special rolls. * The average daily SSR playback volume was 4.3 gigabits for Ahead, and 4.1 gigabits for Behind. Week 33 (Aug 15-21) * Ahead has 480 kbps passes on Monday, Aug 15 (D63), Tuesday, Aug 16 (D14), Wednesday, Aug 17 (D14), Thursday, Aug 18 (D14), and Friday, Aug 19 (D14) There are 8 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Wednesday, Aug 17, twice on Friday, Aug 19, and Sunday, Aug 21, all using station 14. There are 15 passes during the week, and overall coverage is 8.1 hours above nominal. Week 34 (Aug 22-28) * The 40th momentum dump on Ahead is scheduled for Wednesday, Aug 24, starting at 15:00 UT. * The 34th momentum dump on Behind is also scheduled for Wednesday, Aug 24, starting at 18:00 UT. * Ahead has 480 kbps passes on Monday, Aug 22 (D63), Wednesday, Aug 24 (D14), Friday, Aug 26 (D63), Saturday, Aug 27 (D14), and Sunday, Aug 28 (D14). There are 11 passes during the week, and overall coverage is nominal. * Behind has a 480 kbps pass on Monday, Aug 22 using station 43. There are 14 passes during the week, and overall coverage is 5.6 hours above nominal. Week 35 (Aug 29-Sep 4) * Ahead has 480 kbps passes on Monday, Aug 29 (D63), Tuesday, Aug 30 (D14), Wednesday, Aug 31 (D63), Thursday, Sep 1 (D14), Friday, Sep 2 (D14), and Sunday, Sep 4 (D14). There are 11 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Monday, Aug 29 (D43), Wednesday, Aug 31 (D14), and Thursday, Sep 1 (D63). There are 14 passes during the week, and overall coverage is 4.6 hours above nominal. Week 36 (Sep 5-11) * Monday, Sep 5 is Labor Day. APL will be closed for the holiday. * Thursday, Sep 8, at 12:37 UT is the opening of the launch window for the GRAIL mission. This is a very intense mission, lasting just 9 months, and will require a lot of track time. This will affect the DSN scheduling for STEREO. Each spacecraft will share the view direction with GRAIL two weeks out of every month. The project is looking into getting support from ESA stations to cover the shortfall. Contingency planning in case of a launch slip is ongoing for the five days starting Sep 8. Contingency planning is expected to mostly affect Ahead. * Ahead has 480 kbps passes on Tuesday, Sep 6 (D14), Thursday, Sep 8 (D43), Friday, Sep 9 (D63 and D14), and Saturday, Sep 10 (D43). There are 11 tracks during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Monday, Sep 5 (D43), Wednesday, Sep 7 (D43), and Saturday, Sep 10 (D63). There are 14 tracks during the week, and overall coverage is nominal. Week 37 (Sep 12-18) * The external network switch at APL will be upgraded on Monday, Sep 12, from 22-24 UT. This will be between tracks. * Ahead has 480 kbps passes on Monday, Sep 12 (D14), Tuesday, Sep 13 (D63), Wednesday, Sep 14 (D14), Thursday, Sep 15 (D63), Friday, Sep 16 (D63), and Saturday, Sep 17 (D63). There are 10 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Monday, Sep 12 (D43 and D63), Tuesday, Sep 13 (D63), Wednesday, Sep 14 (D63), Thursday, Sep 15 (D63), Friday, Sep 16 (D43 and D63), Saturday, Sep 17 (D14), and Sunday, Sep 18 (D63). There are 10 passes during the week, and overall coverage is nominal. * There is a gap of 17 days in coverage from southern hemisphere stations for the Ahead spacecraft starting in week 37. This will affect the accuracy of the ephemeris calculations. Use of the ESA New Norcia station would mitigate this problem. However, since there will be three weeks of tracking before this outage, there should be no problem with the ephemeris calculations. Week 38 (Sep 19-25) * Ahead has 480 kbps passes on Thursday, Sep 22 (D14), and Friday, Sep 23 (D63). There are 9 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Monday, Sep 19 (D63), Tuesday, Sep 20 (D63), Wednesday, Sep 21 (D63), Thursday, Sep 22 (D63), Friday, Sep 23 (D63), Saturday, Sep 24 (D43 and D63), and Sunday, Sep 25 (D63). However, many of these 70 meter passes are short. There are 11 passes during the week. Coverage is about two hours short on Thursday, Sep 22, and an hour short on Friday, Sep 23. This may be close for the in situ instruments. Week 39 (Sep 26 - Oct 2) * Ahead has 480 kbps passes on Tuesday, Sep 27 (D14 and D43), Wednesday, Sep 28 (D14), and Thursday, Sep 29 (D14). There are 11 passes during the week. Coverage is about 1.6 hours short on Monday, Sep 26. * Behind has 480 kbps passes on Tuesday, Sep 27 (D14), Wednesday, Sep 28 (D14), Friday, Sep 30 (D63), and Saturday, Oct 1 (D63). There are 9 passes during the week, and coverage is short about 2-4 hours each day for Tuesday-Thursday, Sep 27-29. Week 40 (Oct 3-9) * The 41st momentum dump on Ahead is scheduled for Tuesday, Oct 4, with ignition starting at 13:30 UT. * The 35th momentum dump on Behind is also scheduled for Tuesday, Oct 4, with ignition starting at 15:00 UT. * Ahead has 480 kbps passes on Monday, Oct 3 (D63), Tuesday, Oct 4 (D63), Thursday, Oct 6 (D14 and D43), Saturday, Oct 8 (D14), and Sunday, Oct 9 (D63). There are 12 passes during the week, and coverage is short about 1-2 hours on both Wednesday and Thursday, Oct 5-6. * Behind has 480 kbps passes on Monday, Oct 3 (D63), Wednesday, Oct 5 (D14), and Sunday, Oct 9 (D14). There are 11 passes during the week, and overall coverage is nominal. Week 41 (Oct 10-16) * Ahead has 480 kbps passes on Monday, Oct 10 (D63), Thursday, Oct 13 (D14), Friday, Oct 14 (D63), Saturday, Oct 15 (D43), and Sunday, Oct 16 (D63 and D43). There are 13 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Tuesday, Oct 11 (D14 and D63), Wednesday, Oct 12 (D14), Saturday, Oct 15 (D43 and D14), and Sunday, Oct 16 (D43). There are 13 passes during the week, and overall coverage is short 4.5 hours, mostly on Friday, Oct 14. Other * There was some discussion about the possible use of ESA stations for STEREO. Still waiting for approval from NASA headquarters. FDF is interested in getting STEREO tracking data from the recent ESA test to validate their code. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 33: M Aug 15 (227) Ahead: 480 kbps downlink on station 63 T Aug 16 (228) Ahead: 480 kbps downlink on station 14 W Aug 17 (229) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 14 T Aug 18 (230) Ahead: 480 kbps downlink on station 14 F Aug 19 (231) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 14 (twice) S Aug 20 (232) S Aug 21 (233) Behind: 480 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 34: M Aug 22 (234) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 43 T Aug 23 (235) W Aug 24 (236) Momentum dumps, Ahead: 15:00 UT, Behind: 18:00 UT Ahead: 480 kbps downlink on station 14 T Aug 25 (237) F Aug 26 (238) Ahead: 480 kbps downlink on station 63 S Aug 27 (239) Ahead: 480 kbps downlink on station 14 S Aug 28 (240) Ahead: 480 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 35: M Aug 29 (241) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 43 T Aug 30 (242) Ahead: 480 kbps downlink on station 14 W Aug 31 (243) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 14 T Sep 01 (244) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 63 F Sep 02 (245) Ahead: 480 kbps downlink on station 14 S Sep 03 (246) S Sep 04 (247) Ahead: 480 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 36: M Sep 05 (248) Behind: 480 kbps downlink on station 43 T Sep 06 (249) Ahead: 480 kbps downlink on station 14 W Sep 07 (250) Behind: 480 kbps downlink on station 43 T Sep 08 (251) Ahead: 480 kbps downlink on station 43 F Sep 09 (252) Ahead: 480 kbps downlink on stations 63 and 14 S Sep 10 (253) Ahead: 480 kbps downlink on station 43 Behind: 480 kbps downlink on station 63 S Sep 11 (254) ------------------------------------------------------------------------------- Scheduled activities for Week 37: M Sep 12 (255) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on stations 43 and 63 T Sep 13 (256) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 63 W Sep 14 (257) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 63 T Sep 15 (258) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 63 F Sep 16 (259) Behind: 480 kbps downlink on stations 43 and 63 S Sep 17 (260) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 14 S Sep 18 (261) Behind: 480 kbps downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 38: M Sep 19 (262) Behind: 480 kbps downlink on station 63 T Sep 20 (263) Behind: 480 kbps downlink on station 63 W Sep 21 (264) Behind: 480 kbps downlink on station 63 T Sep 22 (265) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 63 F Sep 23 (266) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 63 S Sep 24 (267) Behind: 480 kbps downlink on stations 43 and 63 S Sep 25 (268) Behind: 480 kbps downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 39: M Sep 26 (269) T Sep 27 (270) Ahead: 480 kbps downlink on stations 14 and 43 Behind: 480 kbps downlink on station 14 W Sep 28 (271) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 14 T Sep 29 (272) Ahead: 480 kbps downlink on station 14 F Sep 30 (273) Behind: 480 kbps downlink on station 63 S Oct 01 (274) Behind: 480 kbps downlink on station 63 S Oct 02 (275) ------------------------------------------------------------------------------- Scheduled activities for Week 40: M Oct 03 (276) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 63 T Oct 04 (277) Momentum dumps, Ahead: 13:30, Behind: 15:00 Ahead: 480 kbps downlink on station 63 W Oct 05 (278) Behind: 480 kbps downlink on station 14 T Oct 06 (279) Ahead: 480 kbps downlink on stations 14 and 43 F Oct 07 (280) S Oct 08 (281) Ahead: 480 kbps downlink on station 14 S Oct 09 (282) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 41: M Oct 10 (283) Ahead: 480 kbps downlink on station 63 T Oct 11 (284) Behind: 480 kbps downlink on stations 14 and 63 W Oct 12 (285) Behind: 480 kbps downlink on station 14 T Oct 13 (286) Ahead: 480 kbps downlink on station 14 F Oct 14 (287) Ahead: 480 kbps downlink on station 63 S Oct 15 (288) Ahead: 480 kbps downlink on station 43 Behind: 480 kbps downlink on stations 43 and 14 S Oct 16 (289) Ahead: 480 kbps downlink on stations 63 and 43 Behind: 480 kbps downlink on station 43 ------------------------------------------------------------------------------- Upcoming events: 2012: * Jan 11 Both: HGA calibration * Jul DAWN - Vesta departure * Jul 11 Both: HGA calibration * Nov 4 Behind: Switch downlink rate to 120 kbps * Nov 13 Total solar eclipse, south Pacific 2013: * May 3 Ahead: Switch downlink rate to 120 kbps * 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 * Oct 15 Behind: End use of 480 kbps on 70 m DSN subnet 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 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