STEREO Weekly Meeting Minutes for 2011-05-24 (Week 21) ANNOUNCEMENTS ------------- * The time of the New Norcia test was incorrectly reported during the telecon. This test has already occurred. See below for details. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 20 * On day 136 (May 16), during the DSS 25 support for Ahead, the uplink was delayed 31 minutes due to a failed pre-track calibration of the transmitter. The uplink was established at 1223z. The SSR pointers were repositioned to minimize data loss. All SSR data were recovered. See DR# G111488 for more information. * On day 137 (May 17), during the DSS 26 support for Ahead, turbo decoder lock was lost briefly beginning at 1508z. This resulted in the loss of six frames of instrument SSR data. * On day 138 (May 18), during the DSS 63 support for Ahead, the uplink was delayed 17 minutes due to a failed pre-track calibration of the transmitter. The uplink was established at 0436z. This anomaly resulted in the loss of several minutes of SECCHI instrument SSR data. See DR# M106325 for more information. * On day 139 (May 19), during the DSS 43 support for Ahead, telemetry lock was lost at 2241z due to the antenna brakes being set. Telemetry lock was not re-established as the support ended four minutes later. All SSR data was recovered. See DR# C108064 for more information. * On day 137 (May 17) on Ahead, and day 138 (May 18) on Behind, the MOps permanent macro release 1.1.9 was loaded to C&DH EEPROM which supports changes for the SECCHI SSR2 partition playback. * On day 138 (May 18), during the DSS 55 support for Behind, turbo decoder lock was lost beginning at 2124z. This resulted in the loss of several minutes of instrument SSR data. See DR# N107353 for more information. * On day 138 (May 18), CCSDS SLE telemetry testing using DSS 63 as a shadow track was conducted successfully in parallel with the DSS 55 committed track. * On day 142 (May 22), during the DSS 43 support for Behind, telemetry lock was intermittently lost beginning at 0713z through 0835z due to heavy rain at Canberra. The SSR pointers were repositioned and all SSR data were recovered. See DR# C108065 for more information. * On day 142 (May 22), during the DSS 15 support for Behind, initial telemetry lock at BOT was delayed two minutes due to the downlink control processor anomaly. After the downlink control processor was power cycled, telemetry lock occurred at 2257z. All SSR data were recovered. See DR# G111554 for more information. * On day 136 (May 16), a warm reboot of the SECCHI BEHIND instrument was conducted at 1712z to further investigate the interference pattern anomaly on the COR1, COR2, and EUVI images. This anomaly was actually corrected by a CEB restart on day 132 (May 12) but was masked by the processing of the background images. The SECCHI team had noted that the CEB restart had changed the interference pattern from variable to stable. However, this turned out to be due to the background images having been corrupted by the data between May 9-12, but this was not recognized until later. The cause of the original anomaly on May 9 is not known, but it appears to be highly significant that the anomaly started at the same time that IMPACT and SWAVES saw a 1553 bus error. Current thinking is that the anomaly was caused by a single event upset from a solitary cosmic ray. There was no solar storm going on at the time. * SECCHI notes that they have a temporary staffing shortage at NRL. Nathan is on vacation until later in the week, and Lynn had a motercycle accident over the weekend. For now, any communications should be routed through Simon. * SECCHI had CME detections on both spacecraft on Friday. The SSR2 data are now down, and writing to the buffers can be re-enabled. * The average daily SSR downlink volume was 6.0 gigabits for Ahead, and 5.5 gigabits for Behind. Week 21 * Ahead has 720 kbps passes on Thursday, May 26 (D43 and D43), and Sunday, May 29 (D63). There are 13 passes during the week, and overall coverage is 2.3 hours above nominal. * Behind has a 720 kbps pass on Saturday, May 28, using station D63. There are 12 passes during the week, and overall coverage is 6 hours above nominal. * There was a test this morning (May 24) between 5-8 UT using Behind with the ESA New Norcia station in Australia. (This was incorrectly reported during the telecon as happening this evening.) No SSR data was played back. Space weather beacon telemetry was unavailable during this test, and the realtime telemetry was not visible in the MOC. Week 22 * Monday, May 30 is Memorial day, which is a holiday at APL. * In preparation for switching to the 160 kbps downlink rate in late June, early July, the DSN time will be increased to 8 hours/day on both spacecraft. * The 32nd momentum dump on Behind will be carried out May 31, with ignition at 16:00 UT. * The 38th momentum dump on Ahead will be carried out Jun 1, with ignition at 14:30 UT. * Ahead has 720 kbps passes on Monday, May 30 (D14 and D43), Thursday, Jun 2 (D14 and D43), and Friday, Jun 3 (D63). There are 13 passes during the week, and overall coverage is nominal. * Behind has 720 kbsp passes on Tuesday, May 31 (D63), Wednesday, Jun 1 (D63), Thursday, Jun 2 (D63), Friday, Jun 3 (D63), Saturday, Jun 4 (D63), and Sunday, Jun 5 (D43). There are 10 passes during the week, and overall coverage is nominal. Week 23 * The IONET switches at APL will be upgraded. The backup switch will be upgraded on Jun 6 between 13-16 UT, which is during a track. This should not have an effect. The primary switch will be upgraded on Jun 8 between the Ahead pass ending at 14:45 UT, and the Behind pass starting at 16:50 UT. * Ahead has 720 kbps passes on Monday, Jun 6 (D14), Wednesday, Jun 8 (D63), Thursday, Jun 9 (D63), Friday, Jun 10 (D14), and Sunday, Jun 12 (D43). There are 12 passes during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Monday, Jun 6 (D63), Tuesday, Jun 7 (D63), Friday, Jun 10 (D63), Saturday, Jun 11 (D63), and Sunday, Jun 12 (D43). There are 14 passes during the week, and overall coverage is nominal. Week 24 * There will be a 2 hour return-to-service track on station 34 for Ahead on Jun 14. There will be no SSR playback during this track. Uplink will be enabled. * There will be test of the 160 kbps downlink during the station 25 pass for Ahead on Wednesday, Jun 15. The prior pass will be a 70 meter station, and a long 70 meter pass follows the test, so no data will be lost. Since the in-situ teams are planning to drop their telemetry rates for 160 kbps, this can be tested during the Jun 15 pass, but this is not required. The telemetry rates will drop to 160 kbps on Jun 27 for Ahead, and Jul 13 for Behind. At the same time that the nominal telemetry rate drops to 160 kbps, the telemetry rate for the 70 meter stations will drop from 720 kbps to 480 kbps. * Ahead has 720 kbps passes on Monday, Jun 13 (D63), Tuesday, Jun 14 (D63 and D14), Wednesday, Jun 15 (D63), and Thursday, Jun 16 (D43). There are 12 passes during the week, and overall coverage is 4.2 hours above nominal. * Behind has 720 kbps passes on Monday, Jun 13, Tuesday, Jun 14, and Wednesday, Jun 15, all using station 63. There are 14 passes during the week, and overall coverage is 1.5 hours above nominal. Week 25 * Ahead has a 720 kbps pass on Friday, Jun 24, using station 43. There are 11 tracks during the week, and overall coverage is 2.1 hours above nominal. * Behind has a 720 kbps pass on Sunday, Jun 26, using station 63. There are 14 tracks during the week, and overall coverage is 8 hours above nominal. Week 26 * Ahead switches downlink rate to 160 kbps on 35 meter stations, and 480 kbps on 70 meter stations on day 178 (Jun 27). * 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. Week 27 * Monday, July 4 is a holiday. * 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. Other * Comet Elenin will be passing very close to the STEREO Behind spacecraft on July 25. SECCHI will look into whether there are any special observations that they will wish to make. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 21: M May 23 (143) T May 24 (144) Behind: Test of 360 kbps 5-8 UTC using ESA New Norcia station W May 25 (145) T May 26 (146) Ahead: 720 kbps downlink on station 43 F May 27 (147) S May 28 (148) Behind: 720 kbps downlink on station 63 S May 29 (149) Ahead: 720 kbps downlink on station 63 Notes: * No beacon broadcast during New Norcia test ------------------------------------------------------------------------------- Scheduled activities for Week 22: M May 30 (150) Memorial Day Ahead: 720 kbps downlink on stations 14 and 43 T May 31 (151) Behind: 720 kbps downlink on station 63 Behind: Momentum dump, 16:00 UT W Jun 01 (152) Ahead: Momentum dump, 14:30 UT Behind: 720 kbps downlink on station 63 T Jun 02 (153) Ahead: 720 kbps downlink on stations 14 and 43 Behind: 720 kbps downlink on station 63 F Jun 03 (154) Ahead: 720 kbps downlink on station 63 Behind: 720 kbps downlink on station 63 S Jun 04 (155) Behind: 720 kbps downlink on station 63 S Jun 05 (156) Behind: 720 kbps downlink on station 43 Notes: * Changing to 8 hours/day of downlink on both spacecraft in preparation for switching to 160 kbps downlink rate in late June, early July. ------------------------------------------------------------------------------- Scheduled activities for Week 23: M Jun 06 (157) Ahead: 720 kbps downlink on station 14 Behind: 720 kbps downlink on station 63 T Jun 07 (158) Behind: 720 kbps downlink on station 63 W Jun 08 (159) Ahead: 720 kbps downlink on station 63 T Jun 09 (160) Ahead: 720 kbps downlink on station 63 F Jun 10 (161) Ahead: 720 kbps downlink on station 14 Behind: 720 kbps downlink on station 63 S Jun 11 (162) Behind: 720 kbps downlink on station 63 S Jun 12 (163) Ahead: 720 kbps downlink on station 43 Behind: 720 kbps downlink on station 43 ------------------------------------------------------------------------------- Scheduled activities for Week 24: M Jun 13 (164) Ahead: 720 kbps downlink on station 63 Behind: 720 kbps downlink on station 63 T Jun 14 (165) Ahead: 720 kbps downlink on stations 63 and 14 Behind: 720 kbps downlink on station 63 Ahead: Return-to-service track on station 34 W Jun 15 (166) Ahead: 720 kbps downlink on station 63 Ahead: Test of 160 kbps on station 25 Behind: 720 kbps downlink on station 63 T Jun 16 (167) Ahead: 720 kbps downlink on station 43 F Jun 17 (168) S Jun 18 (169) S Jun 19 (170) ------------------------------------------------------------------------------- Scheduled activities for Week 25: M Jun 20 (171) T Jun 21 (172) W Jun 22 (173) T Jun 23 (174) F Jun 24 (175) Ahead: 720 kbps downlink on station 43 S Jun 25 (176) S Jun 26 (177) Behind: 720 kbps downlink on station 63 ------------------------------------------------------------------------------- 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 ------------------------------------------------------------------------------- Upcoming events: 2011: * Jul 13 Behind: Switch downlink rate to 160 kbps * Jul 13 Behind: End use of 720 kbps on 70 m DSN subnet * Jul 13 Both: HGA calibration * Jul 25 Behind: Close approach by comet Elenin * Jul DAWN - Vesta arrival 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