STEREO Weekly Meeting Minutes for 2014-04-29 (Week 18) ANNOUNCEMENTS ------------- * Planning continues on the situation with the high HGA feed temperatures on both spacecraft, due to the decreasing SPE angle between the Sun and Earth. See below for details. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 17 (Apr 21-27) * On day 111 (Apr 21), during the DSS-63 support for Ahead, turbo decoder lock was lost intermittently between 0838z and 0839z. This was due to a late uplink sweep that resulted from maintenance completing repairs on the transmitter which had previously been declared red. This anomaly resulted in loss of 731 frames of SSR data. See DR #M107916 for more information. * On day 114 (Apr 24), during the DSS-55 support for Ahead, turbo decoder lock was lost briefly at 1411z. This anomaly resulted in the loss of one frame of SSR data. * On day 115 (Apr 25), during the DSS-55 support for Ahead, initial telemetry lock was established 2.4 hours late at 0938z due to the Automated Link Build at the station not being able to configure for the support. Once the issue was corrected and the downlink established, all SSR pointers were repositioned to avoid data loss. See DR #M107950 for more information. Later in the track, turbo decoder lock was lost briefly at 1109z. This anomaly resulted in the loss of six frames of SSR data. * On day 111 (Apr 21), during the DSS-63 support for Behind, turbo decoder lock was lost intermittently between 1252z/1302z (23941 frames dropped) and 1407z/1411z (16235 frames dropped) due to heavy rain at the station. SSR pointers were repositioned to recovery the first set of lost data, but not the second set. See DR #M107917 for more information. * On day 113 (Apr 23), during the DSS-54 support for Behind, turbo decoder lock was lost briefly at 1541z. This anomaly resulted in the loss of one frame of SSR data. * On day 116 (Apr 26), during the DSS-55 support for Behind, turbo decoder lock was lost briefly at 1239z. This anomaly resulted in the loss of four frames of SSR data. * On day 116 (Apr 26), during the DSS-15 support for Behind, turbo decoder lock was intermittently between 2002z and 2010z. This anomaly resulted in the loss of 725 frames of SSR data. See DR #N109542 for more information. * The average daily SSR playback volume during the week was 5.2 gigabits for Ahead, and 5.0 gigabits for Behind. Week 18 (Apr 28-May 4) * MOps macro 1.1.20 is being loaded onto both spacecraft today (Apr 29), to assist in downloading the attitude history data. * The 67th momentum dump on Ahead is scheduled for Wednesday, Apr 30, with ignition at 15:00 UT. * New HGA soft stop parameters will be loaded onto G&C RAM on both spacecraft on Thursday, May 1. The HGA on Ahead will be limited to 6.6 degrees off the Sun, and the HGA on Behind will be limited to 6.1 degrees. These limits are expected to be reached sometime in the fall and winter of this year respectively. The current worst case scenario is that all the instruments, including SWAVES, will be turned off between Sep 2014-Nov 2015 for Ahead, and between Dec 2014-Dec 2015 for Behind. All possible options are still being considered. A more detailed telecon describing this will take place later in the week, and will also be discussed during the upcoming SWG telecon still in the process of being scheduled. * Roll maneuvers will be scheduled to calibrate the LGA at small angles. The same roll rate will be used as during conjunction. This will be about a three hour test. * Tests of off-pointing the HGA by up to ~9 degrees to map out the side lobes will be scheduled. Only the HGA will be off-pointed--the spacecraft will continue to point to the Sun. * Mercury transitted the disk as seen from Behind earlier today (Apr 29) from approximately 1:49-06:08 UT. SECCHI observations cover a longer time to include the COR1 telescope. * Ahead has 12 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Apr 29 (D14 at 720 kbsp, D43), Wednesday, Apr 30 (D43), Thursday, May 1 (D43 at 720 kbsp), and Sunday, May 4 (D63, D14, both at 720 kbps). The following passes will be carried out at 160 kbps: Monday, Apr 28 (D54), Wednesday, Apr 30 (D55), and Friday, May 2 (D24). The station 26 pass on Saturday, May 3, will be carried out at 240 kbps. * Behind has 13 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Apr 28 (D63 at 720 kbps), Wednesday, Apr 30 (D43, D14, both at 720 kbps), and Thursday, May 1 (D43 at 720 kbps). The following passes will be carried out at 160 kbps: Thursday, May 1 (D55, D24), Friday, May 2 (D55), Saturday, May 3 (D55, D25), and Sunday, May 4 (D55). The following station 26 passes will be carried out at 240 kbps: Tuesday, Apr 29, Friday, May 2, and Sunday, May 4. Week 19 (May 5-11) * The 62nd momentum dump on Behind is scheduled for Tuesday, May 6, with ignition at 23:30 UT. * Ahead has 8 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, May 6 (D63 at 720 kbps), and Saturday, May 10 (D43, D14 at 720 kbps). The following passes will be carried out at 160 kbps: Thursday, May 8 (D25), and Sunday, May 4 (D55). The station 26 pass on Friday, May 9, will be carried out at 240 kbps. * Behind has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, May 5 (D63 at 720 kbps), and Friday, May 9 (D43 at 720 kbps). The following passes will be carried out at 160 kbps: Tuesday, May 6 (D25), Thursday, May 8 (D55, D24), and Saturday, May 10 (D55, D25). The station 26 pass on Sunday, May 11, will be carried out at 240 kbps. Week 20 (May 12-18) * MOps macro 1.1.20 will be loaded onto EEPROM on both spacecraft on May 18. * Ahead has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, May 12 (D14 at 720 kbps), Thursday, May 15 (D63 at 720 kbps), and Friday, May 16 (D43). The following passes will be carried out at 160 kbps: Tuesday, May 13 (D26), Wednesday, May 14 (D55), Thursday, May 15 (D25), and Saturday, May 17 (D55). The following station 26 passes will be carried out at 240 kbps: Wednesday, May 14, Friday, May 16, and Sunday, May 18. * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, May 12 (D14 at 720 kbps), Friday, May 16 (D63), and Saturday, May 17 (D43). The following passes will be carried out at 160 kbps: Tuesday, May 13 (D54), Wednesday, May 14 (D54), Thursday, May 15 (D55, D25), Friday, May 16 (D25), Saturday, May 17 (D65), and Sunday, May 18 (D54). The station 26 pass on Saturday, May 17, will be carried out at 240 kbps. Week 21 (May 19-25) * The 30th SECCHI stepped calibration roll on Ahead is scheduled for May 20, starting at 14:45 UT. The system momentum is expected to be 1 N-m-s. * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes, all using station 14 at 720 kbps, are scheduled for Tuesday, May 20, Friday, May 23, and Sunday, May 25. The following passes will be carried out at 160 kbps: Wednesday, May 21 (D55), and Saturday, May 24 (D65). The following station 26 passes will be carried out at 240 kbps: Monday, May 19, and Thursday, May 22. * Behind has 11 passes during the week, and overall coverage is nominal. 70 meter passes, all at 720 kbps, are scheduled for Monday, May 19 (D63), Wednesday, May 21 (D14), and Friday, May 23 (D63). The following passes will be carried out at 160 kbps: Tuesday, May 20 (D24), Thursday, May 22 (D54), Friday, May 23 (D24), and Saturday, May 24 (D55, D15). The station 26 pass on Sunday, May 25, will be carried out at 240 kbps. Week 22 (May 26-Jun 1) * Ahead has 12 passes during the week, and overall coverage is nominal. 70 meter passes, all at 720 kbps, are scheduled for Monday, May 26 (D14), Friday, May 30 (D63), and Saturday, May 31 (D63). The following passes will be carried out at 160 kbps: Tuesday, May 27 (D55), Friday, May 30 (D26), and Sunday, Jun 1 (D25). The station 26 pass on Wednesday, May 28, will be carried out at 240 kbps. * Behind has 8 passes during the week, and overall coverage is nominal. 70 meter passes, all at 720 kbps, are scheduled for Monday, May 26 (D63), Tuesday, May 27 (D14), and Saturday, May 31 (D14). The following station 55 passes will be carried out at 160 kbps: Wednesday, May 28, Thursday, May 29, and Friday, May 30. The station 26 pass on Sunday, Jun 1, will be carried out at 240 kbps. Other * A cross-support agreement with ESA is still in the process of being worked on. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 18: M Apr 28 (118) T Apr 29 (119) Behind: Mercury transit W Apr 30 (120) Ahead: Momentum dump, 15:00 UT T May 01 (121) F May 02 (122) S May 03 (123) S May 04 (124) ------------------------------------------------------------------------------- Scheduled activities for Week 19: M May 05 (125) T May 06 (126) Behind: Momentum dump, 23:30 UT W May 07 (127) T May 08 (128) F May 09 (129) S May 10 (130) S May 11 (131) ------------------------------------------------------------------------------- Scheduled activities for Week 20: M May 12 (132) T May 13 (133) W May 14 (134) T May 15 (135) F May 16 (136) S May 17 (137) S May 18 (138) ------------------------------------------------------------------------------- Scheduled activities for Week 21: M May 19 (139) T May 20 (140) Ahead: SECCHI stepped calibration roll, 14:45 UT W May 21 (141) T May 22 (142) F May 23 (143) S May 24 (144) S May 25 (145) ------------------------------------------------------------------------------- Scheduled activities for Week 22: M May 26 (146) T May 27 (147) W May 28 (148) T May 29 (149) F May 30 (150) S May 31 (151) S Jun 01 (152) ------------------------------------------------------------------------------- Upcoming events: 2014: * Sep 07-Nov 15 Behind: Passage of Comet Siding Spring through HI2-B * Sep 21 MAVEN arrival at Mars * Oct 17 Behind: Comet Siding Spring encounter with Mars 2015: * Jan 14 - Mar 19 (TBC) Behind: Spacecraft behind Sun * Mar DAWN - Ceres arrival * Feb 11 - Jul 08 (TBC) Ahead: Spacecraft behind Sun * Aug 25 - Oct 19 (TBC) Behind: Possible interference from Sun * Jul DAWN - End of nominal mission 2016: * Jul 5 Juno arrival at Jupiter 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