STEREO Weekly Meeting Minutes for 2011-06-28 (Week 26) ANNOUNCEMENTS ------------- * There will be a network outage at APL on Sunday, Jul 10, between 11-23 UT. See below for details. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 25 (Jun 20-26) * On day 173 (Jun 22), during the DSS 25 support for Ahead, real-time data and commanding were lost at 1145z due to a configuration anomaly at the Goldstone complex. At 1158z, all connections were restored. This anomaly resulted in the loss of 13 minutes of real-time data and commanding. All SSR data were recovered. See DR# N107442 for more information. * On day 177 (Jun 26), during the DSS 26 support for Ahead, turbo decoder lock was lost briefly beginning at 1810z. This resulted in the loss of six frames of instrument SSR data. A DR has been requested. * On day 172 (Jun 21), MOps permanent macro release 1.1.12 and DHS release 1.1.5 were loaded to C&DH RAM on both spacecraft. These changes increase the data returned each track by about 20 minutes by playing back the S/C housekeeping data during the OWLT before the uplink sweep for downlink rates 240, 160, and 120 kbps. * On day 171 (Jun 20), during the DSS 65 support for Behind, turbo decoder lock was lost intermittently beginning at 1855z and again at 1939z. This resulted in the loss of five frames of instrument SSR data. See DR# N107430 for more information. * On day 173 (Jun 22), during the DSS 65 support for Behind, turbo decoder lock was lost briefly beginning at 1847z. This resulted in the loss of eight frames of instrument SSR data. See DR# N107441 for more information. * On day 177 (Jun 26), during the DSS 63 support for Behind, turbo decoder lock was lost briefly beginning at 1925z. This resulted in the loss of 11 frames of instrument SSR data. A DR has been requested. * The average daily SSR playback volume was 5.9 gigabits for Ahead, and 5.9 gigabits for Behind. * A question was raised about missing data for all instruments on Behind on day 169 (Jun 18) between about 15:50 and 20:15 UT. This was caused by a DCD crash that affected the entire JPL complex. The report in the previous week stated that all SSR data were recovered, but the missing data is now being sought for at the station. DR# M106372 covers this anomaly. Week 26 (Jun 27-Jul 3) * Track coverage for the Ahead spacecraft using station 63 on Monday, Jun 27, was cut off about 15 minutes early to assist with the THEMIS-B (ARTEMIS) orbital insertion. Pointers were backed up, and no SSR data were lost. * Turbo decoder lock was lost momentarily during the station 63 support for Behind yesterday (Jun 27). * Link issues between Goddard and JPL affected the station 15 pass for Ahead this morning (Jun 28). The restricted IONET was switched from prime to backup and then back to prime. Pieces of the network will be switched over during a period of 35 minutes starting at 17:30 UT. This shouldn't affect the planned PLASTIC flight software load, but the IMPACT LET patch on Ahead will probably be delayed a few minutes. * Ahead switched downlink rate to 160 kbps on 34 meter stations, and 480 kbps on 70 meter stations yesterday (Jun 27), starting with the station 15 pass at 15:40 UT. 480 kbps is the lowest rate that Ahead is projected to use with 70 meter stations--Behind will drop to 360 kbps for periods near the far side. * The restricted IONET will switch over to backup tomorrow (Jun 29) between 13-16 UT. This will affect the Ahead pass; realtime telemetry will be momentarily lost. The time was picked to not interfere with the MESSENGER mission. * Ahead has 480 kbps passes on Thursday, Jun 30 (D63), and Sunday, Jul 3 (D43). There are 10 passes during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Monday, Jun 27, Wednesday, Jun 29, Thursday, Jun 30, Friday, Jul 1, and Saturday, Jul 2, all using station 63. There are 12 passes during the week, and overall coverage is nominal. * The IMPACT/PLASTIC IDPU had a memory checksum error yesterday (Jun 27) on Ahead that affected PLASTIC beacon telemetry. The error affected a bit related to telemetry, possibly time-stamping. The IMPACT team was able to download a copy of the memory, and fix the bit error within a few hours. Week 27 (Jul 4-10) * Monday, July 4 is a holiday, so if you need to command please contact the MOC ahead of time. * Switch over to Space Link Extension (SLE) protocol will take place on Ahead on day 187 (Jul 6) during the DSS 14 track starting at 11:05 UT, and on Behind on day 188 (Jul 7) during the station 65 track starting at 18:00 UT. The date for Behind was changed to be further from the Jul 4 holiday. Both the switches will take place during business hours. * Network switch replacements at APL are scheduled for Sunday, Jul 10, between 11-23 UT. This will affect all external network connectivity at APL, and no realtime data will be available for passes for both spacecraft. The RIONet will be available for monitoring track operations. * Ahead has 480 kbps passes on Tuesday, Jul 5 (D63 and D14), Wednesday, Jul 6 (D63 and D14), Thursday, Jul 7 (D14), and Friday, Jul 8 (D63). There are 13 passes during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Tuesday, Jul 5 (D63), Friday, Jul 8 (D43), and Sunday, Jul 10 (D63). There are 12 passes during the week, and overall coverage is nominal. Week 28 (Jul 11-17) * Behind will switch to the 160 kbps rate for 34 meter stations, and 480 kbps for 70 meter stations, starting with the station 55 pass on Jul 13. * Both spacecraft will have the 14th HGA calibration on Jul 13, with Ahead starting at 15:00 UT, and Behind starting at 16:00 UT. Preparation for the maneuvers will start about an hour in advance, and the procedure will take about 1-1.5 hours to complete. The spacecraft will be rolled by 0.5 degrees in each direction. * Behind will have the 33rd momentum dump on Tuesday, Jul 12, starting at 19:30 UT. * Ahead will have the 39th momentum dump on Thursday, Jul 14, starting at 15:00 UT. * Ahead has 480 kbps passes on Tuesday, Jul 12, and Saturday, Jul 16, both using station 43. There are 10 passes during the week, and overall coverage is 3.6 hours above nominal. * Behind has 720 kbps passes on Tuesday, Jul 12 (D43 and D63), and 480 kbps passes on Thursday, Jul 14 (D43), Friday, Jul 15 (D43 and D63), and Sunday, Jul 17 (D43). There are 15 passes during the week, and overall coverage is 4.1 hours above nominal. Week 29 (Jul 18-24) * Ahead has 480 kbps passes on Monday, Jul 18, Tuesday, Jul 19, Wednesday, Jul 20, and Thursday, Jul 21, all using station 14. There are 8 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Thursday, Jul 21, Friday, Jul 22, and Saturday, Jul 23, all using station 63. There are 13 passes during the week, and overall coverage is 3 hours above nominal. Week 30 (Jul 25-31) * The 18th SECCHI stepped calibration roll on Ahead is scheduled for Tuesday, day 207 (Jul 26), starting at 7:15 UT. This is the midpoint roll. System momentum is expected to be about 6 N-m-s. * Ahead has 480 kbps passes on Monday, Jul 25, Tuesday, Jul 26, and Wednesday, Jul 27, all using station 63. There are 13 passes during the week, and overall coverage is 1.6 hours above nominal. * Behind has 480 kbps passes on Friday, Jul 29, using stations 14 and 43. There are 14 passes during the week, and overall coverage is 3 hours above nominal. Other * The test of the roll maneuver to observe Comet Elenin from Behind is expected to be scheduled sometime in week 29. It will probably be toward the end of the week due to system momentum. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 26: M Jun 27 (178) Ahead: Switch downlink rate to 160 kbps, 480 kbps for 70 m Behind: 720 kbps downlink on station 63 T Jun 28 (179) W Jun 29 (180) Behind: 720 kbps downlink on station 63 T Jun 30 (181) Ahead: 480 kbps downlink on station 63 Behind: 720 kbps downlink on station 63 F Jul 01 (182) Behind: 720 kbps downlink on station 63 S Jul 02 (183) Behind: 720 kbps downlink on station 63 S Jul 03 (184) Ahead: 480 kbps downlink on station 43 ------------------------------------------------------------------------------- Scheduled activities for Week 27: M Jul 04 (185) Independence day T Jul 05 (186) Ahead: 480 kbps downlink on stations 63 and 14 Behind: 720 kbps downlink on station 63 W Jul 06 (187) Ahead: 480 kbps downlink on stations 63 and 14 T Jul 07 (188) Ahead: 480 kbps downlink on station 14 F Jul 08 (189) Ahead: 480 kbps downlink on station 63 Behind: 720 kbps downlink on station 43 S Jul 09 (190) S Jul 10 (191) Behind: 720 kbps downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 28: M Jul 11 (192) T Jul 12 (193) Behind: Momentum dump, 19:30 UT Ahead: 480 kbps downlink on station 43 Behind: 720 kbps downlink on stations 43 and 63 W Jul 13 (194) Behind: Switch downlink rate to 160 kbps, 480 kbps for 70 m HGA calibration, Ahead: 15:00 UT, Behind: 16:00 UT T Jul 14 (195) Ahead: Momentum dump, 15:00 UT Behind: 480 kbps downlink on station 43 F Jul 15 (196) Behind: 480 kbps downlink on stations 43 and 63 S Jul 16 (197) Ahead: 480 kbps downlink on station 43 S Jul 17 (198) Behind: 480 kbps downlink on station 43 Notes: * Dawn expected to achieve orbit about Vesta around Jul 16. ------------------------------------------------------------------------------- Scheduled activities for Week 29: M Jul 18 (199) Ahead: 480 kbps downlink on station 14 T Jul 19 (200) Ahead: 480 kbps downlink on station 14 W Jul 20 (201) Ahead: 480 kbps downlink on station 14 T Jul 21 (202) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 63 F Jul 22 (203) Behind: 480 kbps downlink on station 63 S Jul 23 (204) Behind: 480 kbps downlink on station 63 S Jul 24 (205) Notes: * Test run of Comet Elenin roll to be tested on Behind during the week. ------------------------------------------------------------------------------- Scheduled activities for Week 30: M Jul 25 (206) Ahead: 480 kbps downlink on station 63 T Jul 26 (207) Ahead: SECCHI stepped calibration roll, 7:15 UT Ahead: 480 kbps downlink on station 63 W Jul 27 (208) Ahead: 480 kbps downlink on station 63 T Jul 28 (209) F Jul 29 (210) Behind: 480 kbps downlink on stations 14 and 43 S Jul 30 (211) S Jul 31 (212) ------------------------------------------------------------------------------- Upcoming events: 2011: * Jul 31 - Aug 12 Behind: Spacecraft rolls to observe comet Elenin 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