STEREO Weekly Meeting Minutes for 2010-02-16 (Week 07) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 6 * Turbo decoder lock was lost momentarily during the station 55 pass for Ahead on day 45 (Feb 14) at 07:34 UT, resulting in the loss of 2 SECCHI frames. This has been a occasionally recurring problem on station 55 since late last fall, but does not occur on every track. * Telemetry lock was lost at 22:51 UT during the station 25 track for Behind on day 43 (Feb 12), due to a problem with the subreflector Y axis. The track was switched to station 15 at 23:15 with downlink only. However, the track ended early at 3:10 UT. This resulted in the loss of several hours of SSR data for all instruments. Also one SWAVES command did not go up, and was retransmitted yesterday (Feb 15). * Turbo decoder lock was lost intermittently during the station 25 pass for Behind on day 44 (Feb 13). This resulted in the loss of several minutes of SSR data. * SECCHI-B had a watchdog reset at 08:39:44 UT on day 42 (Feb 11). The SECCHI team was able to recover the instrument back to operational mode by 13:25 UT, in spite of the blizzard. * The average daily SSR downlink was 5.5 gigabits for Ahead, and 5.4 gigabits for Behind. Week 7 * PLASTIC successfully commanded voltage changes on Ahead this morning (Feb 16). * 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. The SECCHI team requests that pointers be moved during the pass to maximize downlink. * The station 25 passes on both spacecraft yesterday (Feb 15) had no problems. Station 25 has an estimated 0.3 dB loss due to the problems with the subreflector Y-axis, but this is well within the 2 dB link margin. * It was reported that station 45 has a problem with its X-band. However, STEREO is not scheduled to use station 45 until next Tuesday (Feb 23). * The DSN Sequence of Events Code S for the use of the 720 kbps telemetry rate has been fixed, and was used for Behind on Sunday (Feb 14). 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 short 3.2 hour track is scheduled for Ahead on Wednesday evening (Feb 17). Week 9 * There is a 25 hour gap between Behind passes Friday to Saturday, Mar 5-6. Pointers will be moved during the pass on Mar 6. Week 10 * The 28th momentum dump will be carried out on Ahead on March 8, with ignition at 15:30 UT. * Daily Savings Time in the U.S. starts on March 14. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- 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) ------------------------------------------------------------------------------- Scheduled activities for Week 09: M Mar 01 (060) T Mar 02 (061) W Mar 03 (062) T Mar 04 (063) F Mar 05 (064) S Mar 06 (065) Behind: Move pointers during pass S Mar 07 (066) ------------------------------------------------------------------------------- Scheduled activities for Week 10: M Mar 08 (067) Ahead: Momentum dump, 15:30 UT T Mar 09 (068) W Mar 10 (069) T Mar 11 (070) F Mar 12 (071) S Mar 13 (072) S Mar 14 (073) Daily Savings Time starts in U.S. ------------------------------------------------------------------------------- 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: 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: Mercury transit 2014: * Apr 29 Behind: Mercury transit 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 2016: 2017: 2018: * Mar 5 Ahead: Mercury transit