STEREO Weekly Meeting Minutes for 2010-01-26 (Week 04) ANNOUNCEMENTS ------------- * Delivery of telemetry data has been delayed over the past week because of a failure of the DSN Central Data Recorder (CDR) at 21:47 on Monday, Jan 18. See below for details. * Telemetry file version numbers for Jan 18-26 are likely to be different than expected, which might affect automatic processing for some of the instrument teams. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 3 * Delivery of telemetry data has been delayed over the past week because of a failure of the DSN Central Data Recorder (CDR) at 21:47 on Monday, Jan 18. The redundant unit was placed online, but started processing from Jan 10 onward for an unknown reason, rather than from the previous day as intended. It was decided by DSN to allow the CDR to continue processing rather than to try stopping it and restarting it. Gradually, all the telemetry data came in, and the CDR is now caught up. However, the MOC is only caught up as far as Jan 23. They plan to process Jan 24 and 25 today, and Jan 26 tomorrow, and will be back to the normal routine on Thursday, Jan 28. * The problems with the CDR only affected the delivery of playback telemetry, and did not affect spacecraft operations. * The station 25 transmitter went off-line at 14:30 UT during the Ahead pass on Jan 18, and was recovered at 15:13 UT. This resulted in the loss of 42 minutes of commanding and tracking data, and several minutes of SSR data for all instruments. * The 27th momentum dump on Ahead was performed on Jan 19, starting at 16:00 UT. A delta-V of 0.0781 m/s was imparted. * Telemetry lock was lost intermittently starting at 20:39 UT during the Behind pass on station 25 on January 21. This resulted in the loss of several minutes of SSR data for all instruments. * Monitor data was lost for 4 minutes during the station 34 pass on Behind on Jan 24. Redundant equipment was brought online to solve the problem. No SSR data were lost. * The rescheduled 12th SECCHI stepped calibration roll on Behind took place successfully on Jan 19, starting at 08:40 UT. * Because of the delayed delivery of telemetry data, no playback statistics are available for the week. * It was noted that telemetry for Jan 21 arrived before that for Jan 20. This is because the MOC has been tweaking their normal processing to accommodate the problem with delayed telemetry file delivery. Week 4 * SECCHI loaded software update 5.15 to Behind at 13:00 this morning (Jan 26). This software load fixes a scheduling problem experienced during the recent warm restart. * A four hour track on Behind is scheduled using station 43 on Jan 28. This is a 70 meter station, and the track will be carried out at 720 kbps. At this rate, it will be possible to read out the entire recorder. Week 5 * SECCHI will load software update 5.15 to Ahead on Tuesday, Feb 2, starting at 17:00 UT. * The 21st momentum dump will be carried out on Behind on Feb 3, starting at 18:00 UT. * Several shorter than usual tracks are scheduled for Ahead during the week. Week 6 * Longer than usual gaps between tracks will occur for both spacecraft during the week. To alleviate this, the MOC will move pointers during the tracks for both Ahead and Behind on day 39 (Feb 8), for Ahead on day 42 (Feb 11). * Behind is scheduled to use the 70 meter station 43 on Feb 14. This track will be carried out at 720 kbps. The pass duration is 7 hours. Week 7 * A 5.4 hour pass using the 70 meter station 43 is scheduled for Behind on Saturday, day 51 (Feb 20). This track will be carried out at 720 kbps. Week 8 * The 12th SECCHI stepped calibration roll on Ahead will be carried out on day 54 (Feb 23), starting at 02:10. This will be the midpoint roll. The system momentum is expected to be 6 N-m-s. * A 3.2 hour track is scheduled for Ahead late Wednesday/early Thursday (Feb 24/25). Other * There was some discussion about how long the use of 720 kbps on the 70 meter stations can be sustained. This needs to be checked, but the current estimate is that this possibility will drop out sometime in the fall of 2010. After that, the rate of 480 kbps can be used, but that possibility will also be lost at some point in the future. The MOC will look into this question, and inform the teams about the expected telemetry rates using the 70 meter stations. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 04: M Jan 25 (025) T Jan 26 (026) Behind: SECCHI software load, 13:00 UT W Jan 27 (027) T Jan 28 (028) Behind: 720 kbps downlink on station 43. F Jan 29 (029) S Jan 30 (030) S Jan 31 (031) ------------------------------------------------------------------------------- Scheduled activities for Week 05: M Feb 01 (032) T Feb 02 (033) Ahead: SECCHI software load, 17:00 UT W Feb 03 (034) Behind: Momentum dump, 18:00 UT T Feb 04 (035) F Feb 05 (036) S Feb 06 (037) S Feb 07 (038) ------------------------------------------------------------------------------- Scheduled activities for Week 06: M Feb 08 (039) Both: Move pointers during pass T Feb 09 (040) W Feb 10 (041) T Feb 11 (042) Ahead: Move pointers during pass F Feb 12 (043) S Feb 13 (044) S Feb 14 (045) Behind: 720 kbps downlink on station 43 ------------------------------------------------------------------------------- Scheduled activities for Week 07: M Feb 15 (046) T Feb 16 (047) W Feb 17 (048) T Feb 18 (049) F Feb 19 (050) S Feb 20 (051) Behind: 720 kbps downlink on station 43 S Feb 21 (052) ------------------------------------------------------------------------------- Scheduled activities for Week 08: M Feb 22 (053) T Feb 23 (054) Ahead: SECCHI stepped calibration roll, 2:10 UT W Feb 24 (055) T Feb 25 (056) F Feb 26 (057) S Feb 27 (058) S Feb 28 (059) ------------------------------------------------------------------------------- Upcoming events: 2010: ICAL-001: Jan 11-15, Feb 15-19, Mar 15-19, Apr 12-16, May 3-7 SECCHI Stepped calibration rolls Ahead: Feb 23, May 18, Aug 10, Nov 2 Behind: Apr 6, Jul 13, Oct 12 * Spring (TBD) SUMI sounding rocket launch http://adsabs.harvard.edu/abs/2008AGUSMSP51B..01A * Apr 8,15 EIT shutterless (TBC) * Apr 19 Ahead: Begin 7 hour daily DSN tracks * Apr 26 Ahead: Switch downlink rate to 240 kbps * Jul 8,15 EIT shutterless (TBC) * Jul 11 Total solar eclipse http://eclipse.gsfc.nasa.gov/SEmono/TSE2010/TSE2010.html * Jul 14 Both: HGA calibration * Sep 7 Both: Begin 8 hour daily DSN tracks * Sep 13 Both: Switch downlink rate to 160 kbps * Nov 15 Behind: Switch downlink rate to 120 kbps 2011: * Jan 12 Both: HGA calibration * Feb 6 STEREO spacecraft at 180 degree separation * Mar 18 Messenger - Mercury orbital insertion * Apr 11 Ahead: Switch downlink rate to 120 kbps * Jul 13 Both: HGA calibration * Aug DAWN - Vesta arrival * Sep 19 Behind: Switch downlink rate to 96 kbps * Sep 26 Ahead: Switch downlink rate to 96 kbps 2012: * Jan 11 Both: HGA calibration * May DAWN - Vesta departure * Jul 11 Both: HGA calibration * Aug Both: Switch downlink rate to 30 kbps * Nov 13 Total solar eclipse, south Pacific 2013: * Dec 12 Ahead: Possible Mercury transit (TBC) 2014: * Apr 29 Behind: Possible Mercury transit (TBC) 2015: * Feb DAWN - Ceres arrival * Jan 10 - Apr 12 Behind: Spacecraft behind Sun * Feb 17 - Aug 2 Ahead: Spacecraft behind Sun * Jul 23 - Nov 10 Behind: Spacecraft behind Sun * Jul DAWN - End of nominal mission