STEREO Weekly Meeting Minutes for 2009-12-01 (Week 49) ANNOUNCEMENTS ------------- * The track for the Ahead momentum dump tomorrow (Dec 2) was shifted to about 2.5 hours earlier because of the STARDUST (NExT) mission being in safe mode. See below for details. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 48 * Telemetry lock was lost intermittently during the Ahead pass on station 54 on day 327 (Nov 23), resulting in the loss of nine frames. IMPACT, PLASTIC, and SECCHI were affected. * Telemetry lock was again lost intermittently during the Ahead pass on station 55, starting at 07:21 UT, resulting in the loss of 16 SSR frames, affecting the IMPACT and SECCHI instruments. * The 11th SECCHI stepped calibration roll on Ahead was carried out on day 328 (Nov 24), starting at 14:15 UT. Ahead reached aphelion on Nov 25 at 05:38 UT. * Command bind was aborted during the Behind pass on station 55 on day 328 (Nov 24), due to an exciter alarm. * Turbo decoder lock was lost momentarily during the station 34 pass on Behind on day 330 (Nov 26) due to the antenna brakes being set during the transition to commercial power. This resulted in the loss of about 2000 SSR frames. * The macro changes needed for the switch to 240 and 120 kbps were loaded on Behind on day 327 (Nov 23). * The average daily SSR playback was 6.1 gigabits on Ahead and the same on Behind. Week 49 * The 26th momentum dump will be carried out on Ahead tomorrow (Dec 2). The track schedule was shifted 2.5 hours earlier to accommodate the Stardust (NExT) mission, which is in safe mode. The track now starts at 11:45, and ignition is now 15:00 UT. There is a track tonight (Dec 1) which can be used for any necessary preparations. The weekly schedule will be available shortly. The SECCHI team requested to be informed by email when it's ready. * Behind switched to 7 hour tracks in preparation for the switch down to 240 kbps. Not all the tracks will be 7 hours in duration, but this will be made up for to some extent by occasionally having additional tracks. * Tests were be made of the 240 and 120 kbps telemetry rates during the 5 hour Behind pass on station 65 yesterday (Nov 30). PLASTIC reported seeing the expected changes in the realtime APIDs. SECCHI saw no problems, but reported seeing single skipped packets during each telemetry rate change, which is to be expected. The SSC reported no problems with the space weather packets during the test. * An additional 7 hour track this afternoon (Dec 1) will also be used for further testing of the 240 kbps downlink rate, including downloading the SSR. * The EEPROMs on Ahead on both IMUs 1 and 2 were successfully refreshed today (Dec 1). * There is a four hour track on Behind tomorrow. Week 50 * Behind will switch to the 240 kbps rate on Dec 8, starting with the pass beginning at 14:20 UT on station 55. Ahead will remain at 360 kbps until April. * There are two four hour tracks on Ahead on Monday, Dec 7, and a 3 hour track on Behind early Tuesday, Dec 8. Week 51 * A four hour track is scheduled for Ahead on Wednesday, Dec 16. Two five hour tracks are scheduled for Behind on Friday, Dec 18. Other * There will be a momentum dump on Behind during week 52. No other significant activities are scheduled for the remainder of the year. * Dan Ossing will be representing STEREO and a DSN customer forum next week. * SECCHI raised a question about the security certificate for the SDS server being out-of-date. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 49: M Nov 30 (334) Behind: Begin 7 hour daily DSN tracks T Dec 01 (335) W Dec 02 (336) Ahead: momentum dump, 15:00 UT T Dec 03 (337) F Dec 04 (338) S Dec 05 (339) S Dec 06 (340) ------------------------------------------------------------------------------- Scheduled activities for Week 50: M Dec 07 (341) Behind: Switch downlink rate to 240 kbps T Dec 08 (342) W Dec 09 (343) T Dec 10 (344) F Dec 11 (345) S Dec 12 (346) S Dec 13 (347) ------------------------------------------------------------------------------- Scheduled activities for Week 51: M Dec 14 (348) T Dec 15 (349) W Dec 16 (350) T Dec 17 (351) F Dec 18 (352) S Dec 19 (353) S Dec 20 (354) ------------------------------------------------------------------------------- Upcoming events: 2009: ICAL-001: Dec 14-18 SECCHI Stepped calibration rolls Ahead: Nov 24 Behind: Dec 22 * Ongoing JOP 222, Origin of SEPS, Target of opportunity 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 * 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 * 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