STEREO Weekly Meeting Minutes for 2012-08-28 (Week 35) ANNOUNCEMENTS ------------- * New .FIN data files are available for days 198-199. See below for details. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 34 (Aug 20-26) * On day 234 (Aug 21), during the DSS-63 support for Ahead, turbo decoder lock was lost intermittently between 0512z and 0639z. The anomaly resulted in the loss of 98 frames of SSR data. See DR# N108310 for more information. * On day 234 (Aug 21), during the DSS-15 support for Ahead, turbo decoder was lost briefly at 1359z. The anomaly resulted in the loss of one frame of SSR data. See DR# N108311 for more information. * On day 235 (Aug 22), during the DSS-55 support for Ahead, turbo decoder lock was lost briefly at 0449z. The anomaly resulted in the loss of one frame of SSR data. See DR# N108313 for more information. * On day 235 (Aug 22), during the DSS-14 support for Ahead, telemetry lock was lost at 1206z when the antenna brakes were set. The antenna was reset to clear the fault and telemetry lock was re-established at 1213z. This anomaly resulted in the loss of several minutes of SSR data for each instrument. See DR# G113149 for more information. * On day 236 (Aug 23), during the DSS-55 support for Ahead, turbo decoder lock was lost briefly at 0535z. The anomaly resulted in the loss of one frame of SSR data. See DR# N108314 for more information. * On day 237 (Aug 24), during the DSS-63 support for Ahead, turbo decoder lock was lost intermittently between 0756z through 0930z. The anomaly resulted in the loss of 182 frames of SSR data. See DR# N108317 for more information. * On day 239 (Aug 26), during the DSS-63 support for Ahead, turbo decoder lock was lost briefly at 0851z. The anomaly resulted in the loss of 35 frames of SSR data. A DR has been requested. * On day 234 (Aug 21), the 49th momentum dump on Ahead was successfully executed at 1530Z, which imparted a delta V of 0.0919 m/sec. * On day 235 (Aug 22), during the DSS-34 support for Behind, turbo decoder lock was lost briefly at 0624z. This anomaly resulted in the loss of three frames of SSR data. See DR# N108312 for more information. * On day 236 (Aug 23), during the DSS-63 support for Behind, turbo decoder lock was lost intermittently beginning at 1317z through 1530z. This anomaly resulted in the loss of 345 frames of SSR * On day 235 (Aug 22), the 44th momentum dump on Behind was successfully executed at 1800Z, which imparted a delta V of 0.0679 m/sec. * The average daily SSR playback volume during the week was 5.1 gigabits for Ahead, and 4.5 gigabits for Behind. * Tests were conducted successfully with the new ESA SLE command server. Week 35 (Aug 27 - Sep 2) * The current (Aug 28) station 14 uplink for Ahead came up late. Commands are going up, but intermittently. Pointers were moved back to reduce data loss, but there may be a momentary in the SSR coverage. * Ahead has 70 meter passes on Monday, Aug 27 (D63 at 720 kbps), Tuesday, Aug 28 (D14), Wednesday, Aug 29 (D14), and Sunday, Sep 2 (D63 at 720 kbsp, D14). There are 10 passes during the week, and overall coverage is nominal. The station 54 passes on Thursday, Aug 30, and Saturday, Sep 1, will both be carried out at 240 kbps. * Behind has 70 meter passes on Tuesday, Aug 28 (D63), and Friday, Aug 31 (D14). There are 14 passes during the week, and overall coverage is nominal. The station 24 pass on Monday, Aug 27, will be carried out at 240 kbps. ESA New Norcia passes are scheduled for Monday, Aug 27, and Sunday, Sep 2. Week 36 (Sep 3-9) * Monday, Sep 3, is Labor Day. * The 22nd SECCHI stepped calibration roll on Behind will be carried out on Tuesday, Sep 4, starting at 11:15 UT. System momentum will be about 4 N-m-s. This is the midpoint roll. Midpoint is actually the week before. * A DSN parameter will be changed on Tuesday, Sep 4, to open the carrier bandwidth in an effort to help troubleshoot the turbo decoder lock issues. * A question was asked about the statistics of the turbo decoder lock losses. No specific statistics are kept, but the behavior appears random. * Ahead has 70 meter passes on Friday, Sep 7 (D14), Saturday, Sep 8 (D14 at 720 kbps), and Sunday, Sep 9 (D63). There are 12 passes during the week, and overall coverage is nominal. * Behind has 70 meter passes on Monday, Sep 3 (D14), Friday, Sep 7 (D63), and Saturday, Sep 8 (D63). There are 12 passes during the week, and overall coverage is nominal. The station 65 pass on Monday, Sep 3, and the station 54 pass on Sunday, Sep 9, will both be carried out at 240 kbps. An ESA New Norcia pass is scheduled for Thursday, Sep 6. Week 37 (Sep 10-16) * Ahead has 70 meter passes on Monday, Sep 10 (D63), Tuesday, Sep 11 (D63), Wednesday, Sep 12 (D14), Saturday, Sep 15 (D14), and Sunday, Sep 16 (D63). There are 10 passes during the week, and overall coverage is nominal. * Behind has 70 meters every day between Tuesday through Sunday, Sep 11-16. There are 9 passes during the week, and overall coverage is nominal. An ESA New Norcia pass is scheduled for Tuesday, Sep 11. Week 38 (Sep 17-23) * The 23rd SECCHI stepped calibration roll on Ahead will be carried out on Tuesday, Sep 18, starting at 08:40 UT. System momentum will be about 4 N-m-s. This is the aphelion roll--aphelion is actually the following week. * The Hubble space telescope will be making special observations of the planet Jupiter on Sep 20 to observe the dimming caused by a transit of Venus across the face of the Sun as seen from Jupiter. These observations will test the ability to extract information about Venus's atmosphere by observing the dimming in multiple bandpasses, and will serve to test how this procedure can be used to explore the atmospheres of exoplanets. Simultaneous observations of the Sun from SDO and STEREO Ahead are desired to monitor possible solar activity which could affect the measurements. * Ahead has 70 meter passes every day of the week, with two on Monday, Sep 17. There are 14 passes during the week, and overall coverage is nominal. An ESA New Norcia pass is scheduled for Tuesday, Sep 18. * Behind has 70 meter passes on Monday, Sep 17 (D63), Wednesday, Sep 19 (D14), Thursday, Sep 20 (D14), and Friday, Sep 21 (D63). There are 12 passes during the week, and overall coverage is nominal. The station 45 passes on Wednesday, Sep 19, and Friday, Sep 21, will be carried out at 240 kbps. ESA New Norcia passes are scheduled for Tuesday, Sep 18, and Sunday, Sep 23. Week 39 (Sep 24-30) * Ahead reaches aphelion on Sep 26. * Sep 30 marks the end of the 2nd extended mission for STEREO. * Momentum dumps are scheduled for both spacecraft during the week, with the 50th dump on Ahead scheduled for Sep 24 at 16:00 UT, and the 45th dump on Behind scheduled for Sep 25 at 15:00 UT. These dumps were scheduled a week early due to track coverage. * The second battery discharge cycling on Ahead is scheduled for the morning of Sep 26. This will be for 2 hours during a station 14 track. * Project Interface Tests (PIT) will be carried out with the Ahead spacecraft on Thursday, Sep 27 for 1.8 hours using station 24, and Sunday, Sep 30 for 3.2 hours using station 26. Realtime data will be flowing during these tests, but there will be no instrument commanding or SSR playback. * Ahead has 70 meter passes every day except Thursday, Sep 27, with two passes on Tuesday, Sep 25, and Sunday, Sep 30. The first 70 meter pass on each of those two days will be at 720 kbps. There are 11 passes during the week, and overall coverage is nominal. * Behind has 70 meter passes on Monday, Sep 24 (D14), Tuesday, Sep 25 (D63 at 720 kbps), Thursday, Sep 27 (D14, D63), and Friday, Sep 28 (D14). There are 9 passes during the week, and overall coverage is nominal. An ESA New Norcia pass is scheduled for Friday, Sep 28. Week 40 (Oct 1-7) * Ahead has 70 meter passes on Monday, Oct 1 (D14), Wednesday, Oct 3 (D63), Saturday, Oct 6 (D63), and Sunday, Oct 7 (D63). There are 11 passes during the week, and overall coverage is nominal. * Behind has 70 meter passes on Monday, Oct 1 (D14 at 720 kbps), Friday, Oct 5 (D43, D14), and Saturday, Oct 6 (D14 at 720 kbps). There are 9 passes during the week, and overall coverage is nominal. An ESA New Norcia pass is scheduled for Thursday, Oct 4. Other * IMPACT had reported seeing additional packets in the Behind .fin files for days 198 and 199 (Jul 16-17) which were not in the previous .ptp files, and which appeared to be corrupt packets. It has now been determined that Ahead packets were incorrectly included in the Behind files when attempting to recover missing data from ESA passes. New .fin files have been produced (version 06) to correct this problem, and a software request has been put in to avoid this problem in the future. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 35: M Aug 27 (240) T Aug 28 (241) W Aug 29 (242) T Aug 30 (243) F Aug 31 (244) S Sep 01 (245) S Sep 02 (246) ------------------------------------------------------------------------------- Scheduled activities for Week 36: M Sep 03 (247) Labor Day T Sep 04 (248) Behind: SECCHI stepped calibration roll, 11:15 UT W Sep 05 (249) T Sep 06 (250) F Sep 07 (251) S Sep 08 (252) S Sep 09 (253) ------------------------------------------------------------------------------- Scheduled activities for Week 37: M Sep 10 (254) T Sep 11 (255) W Sep 12 (256) T Sep 13 (257) F Sep 14 (258) S Sep 15 (259) S Sep 16 (260) ------------------------------------------------------------------------------- Scheduled activities for Week 38: M Sep 17 (261) T Sep 18 (262) Ahead: SECCHI stepped calibration roll, 08:40 UT W Sep 19 (263) T Sep 20 (264) Ahead: Venus transit as seen from Jupiter F Sep 21 (265) S Sep 22 (266) S Sep 23 (267) ------------------------------------------------------------------------------- Scheduled activities for Week 39: M Sep 24 (268) Ahead: Momentum dump, 16:00 UT T Sep 25 (269) Behind: Momentum dump, 15:00 UT W Sep 26 (270) T Sep 27 (271) F Sep 28 (272) S Sep 29 (273) S Sep 30 (274) ------------------------------------------------------------------------------- Scheduled activities for Week 40: M Oct 01 (275) T Oct 02 (276) W Oct 03 (277) T Oct 04 (278) F Oct 05 (279) S Oct 06 (280) S Oct 07 (281) ------------------------------------------------------------------------------- Upcoming events: 2012: * Aug DAWN - Vesta departure * 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