STEREO Weekly Meeting Minutes for 2010-06-15 (Week 24) ANNOUNCEMENTS ------------- INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 23 * The antenna brakes were set just before the end of the station 25 pass for Ahead on day 159 (Jun 8), and the signal was lost for the last 17 minutes of the pass. This resulted in the loss of about 1 hour of SSR data for all instruments. * In situ partitions on Behind started overwriting on day 159 (Jun 8) due to a 10 hour shortage of track coverage during the week. This continued to happen intermittently during the week. The situation is expected to continue through the current week, up through Saturday, June 19. * Last week it was mentioned that PLASTIC was generating telemetry at too fast a rate. The MOC now reports that the PLASTIC rate has leveled off to be closer to the IMPACT rate. The IMPACT and PLASTIC teams report that when the IMPACT burst mode was turned off to lower the telemetry rate, this resulted in too much data going to the PLASTIC SSR partition. The IMPACT burst mode was turned back on for both spacecraft, and the PLASTIC telemetry rate returned to normal. However, no increase was seen in the size of the PLASTIC level-0 telemetry files, suggesting that the extra PLASTIC telemetry may have been duplicate packets. APL is looking into this. * New DFD table entries were uploaded to Behind on day 159 (Jun 8) during the station 54 pass to not play back the SECCHI SSR2 buffer unless requested. This is expected to relieve stress on the overall telemetry system, and allow more in situ data to be collected. * The soft command loss timer was re-enabled on Behind on day 159 (Jun 8) during the station 54 pass. This was previously disabled because of DSN contentions involved with the Planet-C launch. * The 24th momentum dump on Behind was carried out on day 160 (Jun 9), imparting a delta-V of 0.0607 m/s. * The average daily SSR downlink was 5.4 gigabits for Ahead, and 3.4 gigabits for Behind. Week 24 * Coverage for the Ahead spacecraft looks good. * Behind has several 5 hour tracks in a row during the week. This will result in the loss of in situ telemetry data. Overall, track coverage for Behind is 6.8 hours short during the week. Track coverage gets better towards the end of the week, and is OK for following weeks. Week 25 * Ahead has short tracks on Monday and Friday. No spacecraft telemetry will be downloaded during these tracks. * Behind has many tracks during the week, and is overall 2.6 hours ahead on track coverage. * The Behind track on Friday, Jun 25, will be on 70 meter station 43. This track will be carried out at 720 kbps. * There are three short tracks on Behind during the week, during which no spacecraft telemetry will be downloaded. These are the station 55 tracks on Monday and Tuesday, and the 70 meter track on station 43 on Friday. Week 26 * Ahead will be 5 hours above nominal coverage during the week. Behind will be slightly under (1.4 hours), but should be okay. * July 1, HGA calibration on Behind starting at 21:00 UT, with 10 hour track. * Behind will have a 720 kbps pass on Jul 3 using the 70 meter station 43 at Canberra. Week 27 * Ahead will be 4.9 hours above nominal coverage during the week, while Behind will be close to nominal. Tracks are spread out well for both spacecraft. Week 28 * An HGA calibration will be carried out on Ahead on Jul 15, starting at 15:00 UT. * There will be a 70 meter track for Ahead on Wednesday, Jul 14, on station 63 in Madrid. This track will be carried out at 720 kbps. * Behind track coverage is 4 hours below nominal during the week. However, these tracks are well spaced, and no data loss is expected. Week 29 * The 31st momentum dump will be carried out on Ahead on Monday, Jul 19, starting at 14:00 UT. * Ahead track coverage will be 4.8 hours above nominal during the week. * Behind will have a momentum dump on Thursday, Jul 22, starting at 17:00 UT. * Behind will be 8 hours above nominal during the week. There is a 3 hour track on Wednesday, Jul 21. No spacecraft telemetry will be downlinked during this track. Other * The SUMI sounding rocket launched has been delayed again due to problems with the launch vehicle. A new launch date has not yet been announced. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- 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) S Jun 19 (170) S Jun 20 (171) Notes: * SUMER campaign, June 18-29 (TBC) * SECCHI 304 A co-observations with Swedish Solar Telescope, 3 days within June 15-22, between 8-12 UT * JOP 227, Doppler shift oscillations of AR loops, June 20-30 * Intermittent data losses for in situ instruments expected through Jun 19 due to insufficient track coverage. ------------------------------------------------------------------------------- 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) Behind: 720 kbps on station 43 S Jun 26 (177) S Jun 27 (178) Notes: * SUMER campaign, June 18-29 (TBC) * SECCHI 304 A co-observations with Swedish Solar Telescope, 3 days within June 15-22, between 8-12 UT * JOP 227, Doppler shift oscillations of AR loops, June 20-30 ------------------------------------------------------------------------------- Scheduled activities for Week 26: M Jun 28 (179) T Jun 29 (180) W Jun 30 (181) T Jul 01 (182) Behind: HGA Calibration, 21:00 UT F Jul 02 (183) S Jul 03 (184) Behind: 720 kbps on station 43 S Jul 04 (185) Notes: * SUMER campaign, June 18-29 (TBC) * JOP 227, Doppler shift oscillations of AR loops, June 20-30 ------------------------------------------------------------------------------- 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) ------------------------------------------------------------------------------- Scheduled activities for Week 28: M Jul 12 (193) T Jul 13 (194) W Jul 14 (195) Ahead: 720 kbps on station 63 T Jul 15 (196) Ahead: HGA Calibration, 15:00 UT F Jul 16 (197) S Jul 17 (198) S Jul 18 (199) ------------------------------------------------------------------------------- Scheduled activities for Week 29: M Jul 19 (200) Ahead: Momentum dump, 14:00 UT T Jul 20 (201) W Jul 21 (202) T Jul 22 (203) Behind: Momentum dump, 17:00 UT F Jul 23 (204) S Jul 24 (205) S Jul 25 (206) ------------------------------------------------------------------------------- Upcoming events: 2010: SECCHI Stepped calibration rolls Ahead: Aug 10, Nov 2 Behind: Jul 13, Oct 12 * Jun/Jul (TBC) SUMI sounding rocket launch http://adsabs.harvard.edu/abs/2008AGUSMSP51B..01A * 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