STEREO Weekly Meeting Minutes for 2011-05-03 (Week 18) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 17 * On day 119 (Apr 29), during the DSS 34 support for Ahead, turbo decoder lock was lost intermittently beginning at 1934z through 0102z the next day. This resulted in the loss of 14 frames of instrument SSR data. See DR# N107295 for more information. * On day 120 (Apr 30), during the DSS 25 support for Ahead, the transmitter tripped off-line at 1514z. To avoid additional SSR data loss, the remainder of the track was downlink only. This anomaly resulted in the loss of several minutes of SSR data for all instruments. See DR# G111420 for more information. * On day 121 (May 1), during the DSS 26 support for Ahead, turbo decoder lock was lost intermittently beginning at 1326z through 1331z. This resulted in the loss of 108 frames of instrument SSR data. See DR# N107296 for more information. * On day 117 (Apr 27), the playback of SECCHI SSR2, special event partition #20, was enabled on Ahead at 1430z. To optimize downlink bandwidth, after playing back the recorded data, the playback was disabled at 119-1911z. * The AHEAD S/C reached perihelion in its orbit on day 118 (Apr 28), and Behind reached perihelion on day 119 (Apr 29). * On day 118 (Apr 28), during the DSS 15 support for Behind, initial telemetry lock at BOT was delayed 46 minutes due to a disk failure on a data server at Goldstone. After the redundant data server was placed on-line, telemetry lock occurred at 0046z. The SSR playback was stopped and SSR pointers were repositioned. All SSR data were recovered. See DR# G111406 for more information. * On day 119 (Apr 29), during the DSS 15 support for Behind, turbo decoder lock was lost briefly beginning at 0432z. This resulted in the loss of seven frames of instrument SSR data. * On day 119 (Apr 29), during the DSS 65 support for Behind, telemetry lock was interrupted at 1954z due to an uplink transfer between the simultaneous return to service track with DSS 63. This anomaly resulted in the loss of several minutes of instrument SSR data. The uplink transfer was done to test out the uplink on station 63. The frequency setting on station 63 to match that of station 65 was performed a minute late, causing the anomaly. * On day 120 (Apr 30), during the DSS 55 support for Behind, turbo decoder lock was lost intermittently beginning at 1840z through 1842z. This resulted in the loss of several minutes of instrument SSR data. * On day 117 (Apr 27), the playback of SECCHI SSR2, special event partition #20, was enabled on Behind at 1904z. * The average daily SSR downlink volume was 5.3 gigabits on Ahead, and 5.4 gigabits on Behind. * The SECCHI team noticed that their SSR2 partition on Behind was not played back for two days over the weekend. This was because the pointers needed to be adjusted. New macros are going up this week which should improve the downlinking of SSR2 data. Week 18 * SECCHI stepped calibration rolls are being carried out on both spacecraft today (May 3). The Ahead roll was this morning, and the Behind roll is occuring during the telecon. These are the perihelion rolls. The actual dates of perihelion are day 118 (Apr 28) for Ahead, and day 119 (Apr 29) for Behind--the rolls were shifted to May 3 due to system momentum. * The station 14 antenna was red at the beinning of the Ahead track yesterday (May 2). This caused about 60% of the track to be missed. Pointers were repositioned. However, the SECCHI SSR1 partitions are close to full, and may overwrite. At 10 AA.M. this morning, the partition was 80% full. * MOps Macro 1.1.9 will be uploaded to RAM on Ahead today (May 3), and to Behind on Wednesday (May 4). This should provide more efficient playback of the SECCHI SSR2 partition. * At the time of the telecon, SLE testing using old data is being conducted for Behind. This should be the last SLE test using old data. Future tests should be conducted as shadow tracks. * There will be an APCA hardware testing for Behind using station 24 on Thursday, May 5, shadowing station 15. This test is associated with the pointing model. * There will be a return-to-service track for Behind on station 24 on Friday, May 6. Operations will be carried out using this track, shadowed by station 15. * The PIT test originally scheduled using station 25 with Behind on Thursday, May 5 has been cancelled. * Ahead has 720 kbps passes on Monday, May 2, Wednesday, May 4, and Sunday, May 8, all using station D14. There are 11 tracks during the week, and overall coverage is nominal. * Behind has a 720 kbps pass on Monday, May 2, using station D43. There are 14 passes during the week, and overall coverage is 9.7 hours above nominal. Week 19 * There is a return-to-service track for station 24 for Ahead on May 9. This will be shadowing a track using station 15. There will be no uplink during this track. Also, it is expected that SLE shadow testing will occur during this track. Instrument teams can expect to see redundant realtime data. * The SECCHI team asked when the last shadow track occurred. This was on Friday. SECCHI noted that this was visible to them as sequence errors. * IONET switch upgrades will occur tomorrow between 19-21 UT, during the station 65 pass for Behind. The IONET connection will be lost, and there will be no commanding or realtime telemetry during this time. Two more switch upgrades are anticipated for the future. * Ahead has a 720 kbps pass on Tuesday, May 10, using station 63, and Sunday, May 15, using station D14. There are 14 passes during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Monday, May 9, Tuesday, May 10, Wednesday, May 11, Thursday, May 12, Saturday, May 14, and Sunday, May 15, all using station D63 for a total of six 70 meter passes. There are 14 passes during the week, and overall coverage is 1.6 hours above nominal. Week 20 * The MOps macros will be copied from RAM to EEPROM on May 17 for Ahead, and May 18 for Behind. * Ahead has a 720 kbps pass on Wednesday, May 18 (D63), Thursday, May 19 (D43), and Sunday, May 22 (D14). There are 12 passes during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Monday, May 16 (D63), Thursday, May 19 (D63), and Sunday, May 22 (D43), for a total of three 70 meter passes. There are 14 passes during the week, and overall coverage is 1.75 hours above nominal. Week 21 * Ahead has a 720 kbps pass on Thursday, May 26 (D43), and Sunday, May 29 (D63). There are 11 passes during the week, and overall coverage is 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. Week 22 * Monday, May 30 is Memorial day, which is a holiday at APL. * The 38th momentum dump on Ahead will be carried out Jun 1, with ignition at 14:30 UT. * The 32nd momentum dump on Behind will be carried out May 31, with ignition at 16:00 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. * 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. Week 23 * Ahead has 720 kbps passes on Monday, Jun 6 (D14), Wednesday, Jun 8 (D63), Thursday, Jun 9 (D63), 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 * Ahead has 720 kbps passes on Monday, Jun 13 (D63), Tuesday, Jun 14 (D63 and D14), Wednesday, Jun 15 (D63), and Thursday, Jun 16 (D63). There are 12 passes during the week, and overall coverage is 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 1.6 hours above nominal. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 18: M May 02 (122) Ahead: 720 kbps downlink on station 14 Behind: 720 kbps downlink on station 43 T May 03 (123) Ahead: SECCHI calibration roll, 08:20 UT Behind: SECCHI calibration roll, 14:15 UT Behind: SLE test, 14-18 UT W May 04 (124) Ahead: 720 kbps downlink on station 14 Behind: IONET switch upgrade 19-21 UT, no commanding T May 05 (125) Behind: APCA hardware test using station D24, shadowing D15 F May 06 (126) Behind: Return-to-service track on D24, shadowed by D15 S May 07 (127) S May 08 (128) Ahead: 720 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 19: M May 09 (129) Ahead: Return-to-service track on station D24 Behind: 720 kbps downlink on station 63 T May 10 (130) Ahead: 720 kbps downlink on station 63 Behind: 720 kbps downlink on station 63 W May 11 (131) Behind: 720 kbps downlink on station 63 T May 12 (132) Behind: 720 kbps downlink on station 63 F May 13 (133) S May 14 (134) Behind: 720 kbps downlink on station 63 S May 15 (135) Ahead: 720 kbps downlink on station 14 Behind: 720 kbps downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 20: M May 16 (136) Behind: 720 kbps downlink on station 63 T May 17 (137) W May 18 (138) Ahead: 720 kbps downlink on station 63 T May 19 (139) Ahead: 720 kbps downlink on station 43 Behind: 720 kbps downlink on station 63 F May 20 (140) S May 21 (141) S May 22 (142) Ahead: 720 kbps downlink on station 14 Behind: 720 kbps downlink on station 43 ------------------------------------------------------------------------------- Scheduled activities for Week 21: M May 23 (143) T May 24 (144) 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 ------------------------------------------------------------------------------- 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) 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 W Jun 15 (166) Ahead: 720 kbps downlink on station 63 Behind: 720 kbps downlink on station 63 T Jun 16 (167) Ahead: 720 kbps downlink on station 63 F Jun 17 (168) S Jun 18 (169) S Jun 19 (170) ------------------------------------------------------------------------------- Upcoming events: 2011: * Jun 27 Ahead: Switch downlink rate to 160 kbps * Jun 27 Ahead: End use of 720 kbps on 70 m DSN subnet * Jul 15 Behind: Switch downlink rate to 160 kbps * Jul 15 Behind: End use of 720 kbps on 70 m DSN subnet * Jul 25 Behind: Close approach by comet Elenin * Jul DAWN - Vesta arrival * Jul 13 Both: HGA calibration 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