STEREO Weekly Meeting Minutes for 2010-06-08 (Week 23) ANNOUNCEMENTS ------------- INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 22 * The PLASTIC SSR partition on Ahead starting overwritting around 17 UT on day 153 (Jun 2). This resulted in the loss of 2 hours of PLASTIC data. It appears that PLASTIC may be recording at a higher rate than normal. The IMPACT and PLASTIC teams are investigating. * Turbo decoder lock was lost momentarily during the station 66 pass for Ahead on day 155 (Jun 4). This resulted in the loss of two frames of SECCHI data. * The 30th momentum dump on Ahead was carried out on Friday, Jun 4, starting at 14:00 UT. A delta-V of 0.0742 m/s was imparted. * Turbo decoder lock was lost intermittently beginning at 00:40 UT on day 156 (Jun 5), and again at 04:04 UT, during the station 15 pass for Behind. This resulted in the loss of 16 telemetry frames. * Turbo decoder lock was again intermittent during another station 15 pass for Behind on day 156 (Jun 5), between 18:20 and 22:54 UT. This resulted in the loss of 103 telemetry frames. * The average daily SSR downlink was 4.5 gigabits for Ahead, and 4.4 gigabits for Behind. Week 23 * Monday June 7 - first track for Ahead on station 65 was only 2.1 hours and was used for science data download only. * The antenna brakes were set just before the end of the station 25 pass for Ahead, and the signal was lost. This may impact the science data. * Friday June 11 Ahead will have a 6.4 hour track on Station 63 with a 720 kbps data rate. * Track coverage for Ahead during the week is 9 hours over the average. * Thursday, Jun 10 there will be two overlapping tracks for Ahead: Station 26 is the main track. Station 25 is running a test during the same time period and should be ignored. DSN requests that the MOC process the data from station 25 to confirm that the data are OK. * The soft command loss timer is being re-enabled on Behind today (Jun 8) * Behind is expected to lose in-situ data starting on Day 160 (Jun 9) and continuing for the next 10 days, through day 170 (Jun 19). Overall, Behind is 10.1 hours short on telemetry coverage during the week. To mitigate this problem, a new DFD table will be uploaded this afternoon (Jun 8) to Behind to not play back the SECCHI SSR2 buffer unless requested. The new table will be uploaded at the beginning of the track, and Behind will be switched to this new DFD during the track. APL will inform SECCHI of when this happens. * There will be a momentum dump on Behind tomorrow (Jun 9), starting at 21:30 UT. Week 24 * Behind is 6.8 hours short in track coverage during the week. Many tracks are 5 hours long. Intermittent in-situ data gaps are expected through Jun 20. Ahead coverage looks good. Week 25 * The first tracks for both spacecraft during the week, on Jun 21, will be very short. These tracks will be entirely devoted to science data. * The 2.5 hour track on Behind on Jun 22 will be entirely devoted to science data. * There are short tracks for both spacecraft on Friday, Jun 25. These tracks will be entirely devoted to science data. The track on Behind will be carried out at 720 kbps. * Track coverage for Ahead is 1.8 hours over, and 2.6 hours over for Behind. Week 26 * July 1, HGA calibration on Behind with 10 hour track. * Behind will have a 720 kbps pass on Jul 3 using the 70 meter station 43 at Canberra. * Ahead will be 8.5 hours above nominal coverage during the week. Behind will be slightly under, but should be okay. Week 27 * Ahead will be 4.9 hours above nominal coverage during the week, while Behind will be close to nominal. Other * The SUMI sounding rocket experiment originally scheduled for today (Jun 8) has been delayed to Jun 18 to investigate a possible problem with the launcher. * There is a campaign being organized to study limb regions during the solar eclipse on Jul 11. Regular synoptic SECCHI data is being requested for this event. * JOP 227 is scheduled to run for several days between Jun 20-30. The exact dates are not yet known. SECCHI will make special observations in support of this JOP. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 23: M Jun 07 (158) T Jun 08 (159) W Jun 09 (160) Behind: Momentum dump, 21:30 UT T Jun 10 (161) Ahead: Engineering test on station 25 F Jun 11 (162) S Jun 12 (163) S Jun 13 (164) ------------------------------------------------------------------------------- Scheduled activities for Week 24: M Jun 14 (165) T Jun 15 (166) W Jun 16 (167) ICAL01, 11 UT T Jun 17 (168) F Jun 18 (169) SUMI sounding rocket launch http://adsabs.harvard.edu/abs/2008AGUSMSP51B..01A S Jun 19 (170) S Jun 20 (171) Notes: * SUMER campaign, June 18-29 (TBC) * JOP 227, Doppler shift oscillations of AR loops, June 20-30 ------------------------------------------------------------------------------- Scheduled activities for Week 25: M Jun 21 (172) T Jun 22 (173) W Jun 23 (174) T Jun 24 (175) F Jun 25 (176) S Jun 26 (178) S Jun 27 (179) ------------------------------------------------------------------------------- Scheduled activities for Week 26: M Jun 28 (180) T Jun 29 (181) W Jun 20 (182) T Jul 01 (183) Behind: HGA Calibration F Jul 02 (184) S Jul 03 (185) S Jul 04 (186) ------------------------------------------------------------------------------- Scheduled activities for Week 27: M Jul 05 (186) T Jul 06 (187) W Jul 07 (188) T Jul 08 (189) F Jul 09 (190) S Jul 10 (191) S Jul 11 (192) ------------------------------------------------------------------------------- Upcoming events: 2010: SECCHI Stepped calibration rolls Ahead: Aug 10, Nov 2 Behind: Jul 13, Oct 12 * 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 * Aug 23 Ahead: End use of 720 kbps on 70 m DSN subnet * Sep 6 Behind: End use of 720 kbps on 70 m DSN subnet * 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 DAWN - Vesta arrival * Jul 13 Both: HGA calibration * Sep 19 Behind: Switch downlink rate to 96 kbps * Sep 26 Ahead: Switch downlink rate to 96 kbps 2012: * Jan 9 Behind: End use of 480 kbps on 70 m DSN subnet * Jan 11 Both: HGA calibration * Jun 25 Ahead: End use of 480 kbps on 70 m DSN subnet * Jul DAWN - Vesta departure * Jul 11 Both: HGA calibration * Aug 20 Both: Switch downlink rate to 30 kbps * Nov 13 Total solar eclipse, south Pacific 2013: * Nov 25 Behind: End use of 360 kbps on 70 m DSN subnet * 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 * May 25 Ahead: End use of 360 kbps on 70 m DSN subnet * Aug 10 Ahead: Begin use of 360 kbps on 70 m DSN subnet * Jul 23 - Nov 10 Behind: Spacecraft behind Sun * Jul DAWN - End of nominal mission 2016: 2017: 2018: * Mar 5 Ahead: Mercury transit