STEREO Weekly Meeting Minutes for 2008-12-30 (Week 01) 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 52 * Continuing transmitter problems on station 15 affected the Ahead pass on day 357 (Dec 22). An additional pass on station 25 was added so that the partititions could be reset. Several minutes of SSR data was lost during the the sweep. * A SWAVES instrument reset occurred on Ahead on day 359 (Dec 24). This is the first time SWAVES-A has reset itself unexpectedly since it was delivered. It has happened once before on SWAVES-B. * Heavy rain at station 45 caused problems with intermittent telemetry during the Behind pass on day 358 (Dec 23) starting at 08:52. In addition, the station switched from generator to commercial power at 09:47, causing the antenna to stop tracking for 28 minutes. These two events caused numerous short gaps in telemetry coverage during the day. * Station 15 had a ranging anomaly during the Behind pass on day 359, resulting in the loss of ranging data. * Telemetry lock was lost for 15 seconds during the Behind pass on station 15 on day 359, starting at 02:44 UT. Some SECCHI data were lost. * The average daily SSR downlink was 6.2 gigabits on Ahead, and 7.3 gigabits on Behind. Week 01 * The station 15 transmitter tripped offline yesterday (Dec 29) during the Behind pass. * A leap second will be added to the spacecraft at the end of day 366 (Dec 31). The instrument teams will see this as a repeat of the second 23:59:59 UT. There will be no tracks during the year rollover. The STEREO software in SolarSoft has been prepared for the upcoming leap second. * APL will be closed for the holidays on both January 1 and 2, so the instrument teams should arrange to send any necessary commands up before then. Week 02 * HGA calibrations are scheduled for both spacecraft on 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. Week 03 * Minor network maintenance is planned at APL between tracks. This should not affect the instrument teams. Other * IMPACT plans to perform some SWEA testing during the first half of January, starting sometime at the end of next week. They will raise the heater settings to explore some possible temperature dependence in the SWEA efficiency. This testing will occur on both spacecraft. The testing is expected to take 10 days to complete, with about 48 hours between each temperature adjustment. They will also be eliminating STE burst data for a month so that longer SWEA and MAG burst data can be sent down. * In looking back over their data, the IMPACT team realizes that the SWEA instruments did not show this problem when the boom was first deployed. Instead the problem gradually developed between Nov 1 and Nov 4, 2006 on both spacecraft, and remains to this day. The problem is manifested as an anomalous peak in counts at 30 eV. They ask whether any spacecraft or instrument activities between Nov 1 to Nov 4, 2006 could be related to this problem. * The SECCHI/COR1 team noticed some unusual short jitter events on Behind on Dec 24 and Dec 27. The G&C team reports that this is due to an expected wheel-speed-avoidance redistribution transient. A similar transient occurred on Dec 20, but was unobserved by COR1 because it fell between exposures. 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) 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) ------------------------------------------------------------------------------- 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 TBD Planned network outage at APL * Jan 22 Start of extended mission * Jan 23 ICAL14, Herschel sounding rocket launch * Jan 24 STEREO at 90 degrees separation * 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 2010: SECCHI Stepped calibration rolls Ahead: Feb 23, May 18, Aug 10, Nov 2 Behind: Apr 6, Jul 13, Oct 12 * Apr Ahead: Switch downlink rate to 160 kbps * Jul 11 Total solar eclipse * Nov 15 Behind: Switch downlink rate to 96 kbps 2011: * Mar 18 Messenger - Mercury orbital insertion * Apr 11 Ahead: Switch downlink rate to 96 kbps * Aug DAWN - Vesta arrival 2012: * May DAWN - Vesta departure 2013: 2014: 2015: * Feb DAWN - Ceres arrival * Jul DAWN - End of nominal mission