STEREO Weekly Meeting Minutes for 2009-10-20 (Week 43) ANNOUNCEMENTS ------------- * The weekly telecon normally scheduled for October 27th will be canceled because of the STEREO Science Working Group meeting occurring at the same time. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 42 * The Ahead pass on station 54 on day 286 (Oct 13) was cut short two hours early because of a problem on the MESSENGER spacecraft. This resulted in the loss of 13.4 hours of SSR data. * The station 25 transmitter went offline four times during the Ahead pass on day 288 (Oct 15), starting at 13:40 UT, near the beginning of track. The transmitter was recalibrated each time, and was stable by 15:44 UT. This resulted in the loss of 48 minutes of commanding and tracking, and 25 minutes of SSR data. The transmitter power was 10 kW, which is sufficient for STEREO. Since then, the data acquisition assembly has been reworked, and the transmitter should now be capable of 17 kW. * The 25th momentum dump for Ahead was carried out on day 288 (Oct 15) at 17:00 UT. A delta-V of 0.0836 m/s was imparted. * The station 26 transmitter was limited to 10 kW during the Behind pass on day 291 (Oct 18). This is sufficient for STEREO. * The average daily SSR downlink was 5.3 gigabits for Ahead, and 5.9 gigabits for Behind. * COR1 noticed a small 3 arc second pointing offset for a few minutes on Oct 17. It was confirmed that this was due to a wheel speed avoidance rule firing. Week 43 * SECCHI-Behind had a watchdog reset at 05:32 UT on Monday (Oct 19), and was recovered by 14:51 UT. * Five hour tracks are scheduled for Ahead on Friday and Saturday (Oct 23, 24), and for Behind on Friday. Week 44 * Behind reaches L5 on day 299 (Oct 26). This is also the third anniversary of the STEREO launch. * Daylight savings ends on day 305 (Nov 1) at 06:00 UT. * Shorter tracks are scheduled for Ahead on Monday (Oct 26) and Friday and Saturday (Oct 30-31), and on Behind on Monday (Oct 26) and Thursday (Oct 29). Week 45 * The 19th momentum dump on Behind is scheduled for Tuesday, day 307 (Nov 3). Other * The MOC asked about switching the beacon mode from convolutional to Turbo encoding. The SSC responded that NOAA is still working on the convolutional code, and does not have a timetable for when it will be completed. NOAA is also looking into the possibility of optimizing the phase modulation to increase the signal-to-noise. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 43: M Oct 19 (292) Behind: SECCHI watchdog reset and recovery, 05:43-15:42 UT T Oct 20 (293) W Oct 21 (294) T Oct 22 (295) F Oct 23 (296) S Oct 24 (297) S Oct 25 (298) Notes: * JOP 224, Solar Tomography with Minimal Solar Rotation, Sep 27-Oct 27 ------------------------------------------------------------------------------- Scheduled activities for Week 44: M Oct 26 (299) Behind: At L5 Lagrange point T Oct 27 (300) W Oct 28 (301) T Oct 29 (302) F Oct 30 (303) S Oct 31 (304) S Nov 01 (305) Daylight savings ends in U.S., 06:00 UT Notes: * JOP 224, Solar Tomography with Minimal Solar Rotation, Sep 27-Oct 27 ------------------------------------------------------------------------------- Scheduled activities for Week 45: M Nov 02 (306) T Nov 03 (307) Behind: Momentum dump, 16:00 UT W Nov 04 (308) T Nov 05 (309) F Nov 06 (310) S Nov 07 (311) S Nov 08 (312) ------------------------------------------------------------------------------- Upcoming events: 2009: ICAL-001: Oct 12-16, Dec 14-18 SECCHI Stepped calibration rolls Ahead: Nov 24 Behind: Dec 22 * Mar 16-Sep LASCO C2pB for Tomography Reconstruction * Mar 27-... JOP 222, Origin of SEPS, Target of opportunity * Sep 27-Oct 27 JOP 224, Solar Tomography with Minimal Solar Rotation * Oct 26 Behind at L5 Lagrange point * Nov 30 Behind: Begin 7 hour daily DSN tracks * Dec 7 Behind: Switch downlink rate to 240 kbps 2010: SECCHI Stepped calibration rolls Ahead: Feb 23, May 18, Aug 10, Nov 2 Behind: Apr 6, Jul 13, Oct 12 * Jan 6 Both: HGA calibration * Jan 7,15 EIT shutterless (TBC) * 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 * 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: 2014: 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