STEREO Weekly Meeting Minutes for 2009-01-06 (Week 02) ANNOUNCEMENTS ------------- * None INSTRUMENT AND SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal, except that the Ahead spacecraft is currently operating on IMU #2. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 01 * On day 366 (Dec 31), the ground receipt time in all telemetry during the station 25 support on Ahead, and the station 15 support on Behind, was mistakenly recorded as January 1, 2009. This affects the time stored in the ground receipt header in the telemetry files, and would also affect playback from the MOC by ground receipt time. Only the ground receipt times were affected--the packet times in the telemetry are correct. No teams report being affected by this bug. It will take about two days of effort to generate corrected level-0 packet files. * The station 15 transmitter tripped offline on day 364 (Dec 29) during the Behind pass. The remainder of the pass was downlink only to minimize SSR data loss. This resulted in the loss of 98 minutes of commanding and tracking data, and several minutes of SSR data loss. * The station 15 transmitter tripped offline again during the Ahead pass on day 1 (Jan 1). The resweep of the uplink caused a few minutes of SSR data loss, affecting mostly SECCHI. * A leap second was added to both spacecraft at the end of day 366 (Dec 31). * SECCHI reports that there was a small telemetry gap in their Ahead data on day 362 (Dec 27) around 23:50 UT. The cause of this gap is unknown. * The average daily SSR playback was 6.2 gigabits on Ahead, and 7.2 gigabits on Behind. Week 02 * The scheduled Ahead track on station 25 yesterday (Jan 5) did not occur because of problems at the station. Two additional tracks were quickly added to minimize the SSR data loss and reset the pointers. This resulted in the SECCHI synoptic partition filling up. * HGA calibrations are scheduled for both spacecraft tomorrow (Jan 7), at 15:30 for Ahead and 18:00 for Behind. This calibration will take 1 to 1.5 hours. The spacecraft will roll by +/- 1 degree during the calibration, in 1/2 degree steps. Longer tracks of 7 hour duration are scheduled so that the SSR telemetry can be recovered. The next HGA calibration is scheduled for April, and is expected to cover a smaller angular range. * The SSC experienced a year rollover problem which affected the processing of the SECCHI beacon images. This was overcome by restarting the relevant scripts by hand on Jan 4, and then reprocessing the telemetry to fill in the missing days. The cause of the rollover problem is still under investigation. Week 03 * Minor network maintenance is planned at APL between tracks. This should not affect the instrument teams. Week 04 * A momentum dump is scheduled for Behind on Jan 21, with ignition at 19:00 UT. * The prime mission ends, and the extended mission starts, on Jan 22. * The two STEREO spacecraft will be at exactly 90 degrees separation on Jan 24. Other * Several activities are planned for the coming year: - The MOC will be switching over to the SOA telemetry protocol with the ground stations. - G&C software load 3.2.6, and a new flight autonomy version, are planned later in the year, contingent on project approval. This will require a momentary switch to EA mode. - The DSN will be switching to a replacement for the current CDR data capture and telemetry system. * Both spacecraft will be switching to 360 kbps telemetry rate in May, with the pass duration increasing to 6 hours. * Both spacecraft will be switching to 240 kbps telemetry rate in August, with the pass duration increasing to 7 hours. This new telemetry rate requires testing. * Behind will be switching to 160 kbps in December, with the pass duration increasing to 8 hours. * Upcoming launches for LRO/LCROSS and Kepler during the year may affect STEREO DSN schedules. * The APL network outage originally planned for last year has not yet been rescheduled. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 01: M Dec 29 (364) T Dec 30 (365) W Dec 31 (366) Leap second added at end of day T Jan 01 (001) F Jan 02 (002) S Jan 03 (003) S Jan 04 (004) ------------------------------------------------------------------------------- Scheduled activities for Week 02: M Jan 05 (005) T Jan 06 (006) W Jan 07 (007) HGA calibration, Ahead: 15:30 UT, Behind: 18:00 UT T Jan 08 (008) ICAL 1, 14:00 UT F Jan 09 (009) S Jan 10 (010) S Jan 11 (011) ------------------------------------------------------------------------------- Scheduled activities for Week 03: M Jan 12 (012) T Jan 13 (013) W Jan 14 (014) T Jan 15 (015) F Jan 16 (016) JOP 80, EIT shutterless S Jan 17 (017) S Jan 18 (018) ------------------------------------------------------------------------------- Scheduled activities for Week 04: M Jan 19 (019) T Jan 20 (020) W Jan 21 (021) Behind: Momentum dump, 19:00 UT T Jan 22 (022) Start of extended mission F Jan 23 (023) S Jan 24 (024) STEREO at 90 degrees separation S Jan 25 (025) ------------------------------------------------------------------------------- Upcoming events: 2009: ICAL-001: Jan 5-9, Jan 26-30, Mar 2-6, Apr 6-10, May 11-22, Jun 15-19 SECCHI Stepped calibration rolls Ahead: Mar 10, Jun 9, Sep 2, Nov 24 Behind: Mar 10, Jun 16, Sep 22, Dec 22 * Jan/Feb TBD Planned network outage at APL * Feb TBD ICAL14, Herschel sounding rocket launch * Feb 17 DAWN - Mars fly-by * Mar 27, Apr 2 JOP 80, EIT shutterless * Apr 15-29 SUMER campaign (TBC), JOPS 210,211,212,214 * Apr 16 SUMI sounding rocket launch * May 18 Ahead: Switch downlink rate to 360 kbps * Jun 1-Jul 10 Sunrise 5-day balloon flight http://star.mpae.gwdg.de/Sunrise/project/publicat/SPIE_2004.pdf * Jun 8 Behind: Switch downlink rate to 360 kbps * Jul 22 Total solar eclipse http://eclipse.gsfc.nasa.gov/SEmono/TSE2009/TSE2009.html * Aug 4 Both: Increase track duration from 4 to 5 hours * Aug 10 Ahead: Switch downlink rate to 240 kbps * Aug 31 Behind: Switch downlink rate to 240 kbps * Sep 10 Ahead at L4 Lagrange point * Sep 29 Messenger - Mercury fly-by * Oct 25 Behind at L5 Lagrange point * Nov 1-Dec 15 SUMER campaign (TBC) * Dec Behind: Switch downlink rate to 160 kbps