STEREO Weekly Meeting Minutes for 2010-05-18 (Week 20) ANNOUNCEMENTS ------------- * Commercial power will be out at APL during Memorial Day weekend starting from 6 P.M. Friday (May 28) to 5 P.M. Monday (May 31). The MOC will be operating on UPS and a generator. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 19 * JPL performed tests of the new data capture and delivery system, which replaces the old CDR, on Ahead between DSN tracks on day 132 (May 12). * The in-situ instrument partitions started overwriting on day 133 (May 13) due to insufficient track coverage. This was in part because the track on day 132 (May 12) was 2.7 hours short. When the IMPACT and PLASTIC partitions reach 95%, only housekeeping data should be written to the partitions. However, the Ahead partitions appeared to continue to fill at the normal rate, and both reached 100% full. The instrument teams will look into this. * Telemetry lock was interrupted at 21:52 UT during the station 25 pass for Behind on day 131 (May 11), due to a loss of communications at Goldstone. This resulted in the loss of several minutes of SSR data for all instruments. * The average daily SSR playback was 3.8 gigabits for Ahead, and 4.4 gigabits for Behind. Part of the reason for the low data volume on Ahead was that SECCHI appeared to be taking less data than could be downloaded. The SECCHI team reports that they've found that the actual data volumes using the current schedules are coming in as less than predicted, and they are looking into it. Week 20 * The Japanese JAXA Planet-C launch, originally scheduled for Monday, May 17 has been postponed until Thursday, May 20, at 21:58 UT. This has resulted in a number of changes in the track schedule. Ahead lost 25 minutes for the Saturday (May 22) track. A short track for Behind on Friday, May 21, and another track on Friday was shortened by 1.7 hours, but an additional 4.6 hour track was added on Thursday, May 20. Overall, STEREO came out a little bit ahead on coverage and track spacing. * Short tracks continue on Behind. Track durations are 5-6 hours instead of 7 hours for the next 10 days. This will result in data gaps for the insitu instruments. Reading of the SSR partitions won't be caught up until May 31. * Ahead will be at perihelion this afternoon (May 18) at 18:57 UT. The 13th SECCHI stepped calibration roll was carried out earlier this morning. * Pointers will be moved during the week on both spacecraft to avoid losing data. * There will be a 70 meter downlink on station 43 for the Ahead spacecraft on May 23. This will be carried out at 720 kbps. Because the pass duration is just 2 hours, only science data will be downlinked. There is a 34 meter station pass for Ahead earlier in the day. * In case Planet-C does not launch on Thursday (May 20) as expected, and the DSN schedule is further disrupted, the soft command loss timer on Behind has been disabled. * Behind will remain in contention for DSN time with a number of existing missions, and with Planet-C for the next few weeks. Week 21 * The SECCHI GT-driven calibration offpoint on Ahead has been rescheduled for Wednesday, May 26, starting at 9:25. This activity lasts about 90 minutes, and will involve very small offpoints. * There is a very short 1.75 hour track for Ahead on Friday, May 28. Only science data will be downloaded during this track. All spacecraft data should be subsequently recovered. * A new autonomy rule will be uploaded to reset pointers during passes when the SSR partitions reach 97% full for SWAVES and SECCHI, and 92% full for IMPACT and PLASTIC. This rule will be installed on Monday, May 24, on Behind, and Wednesday, May 26, on Ahead. * Commercial power will be out at APL during Memorial Day weekend starting at 6 P.M. on Friday (May 28) to 5 PM on Monday (May 31). The MOC will be operating on UPS and a generator. Phones and email should be working. There should be no impact to the STEREO project. * There are a number of short tracks for Behind during the week. The insitu partitions are expected to be filled several times. Full recovery is not expected until Monday, May 31 (Memorial Day). Week 22 * There will be a momentum dump on Ahead on Friday, Jun 4, starting at 14:00 UT. * Behind should be caught up on Monday. May start to loss insitu data toward the end of the week. Week 23 * Behind is expected to lose insitu data starting at the beginning of the week. Most tracks are only 5 hours in duration. Total track coverage is 10 hours short during the week. Ahead coverage looks okay. * There will be a momentum dump on Behind on 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 insitu data gaps are expected through Jun 20. Ahead coverage looks good. Other * SECCHI points out that when the recorders are full, it takes longer for the data to reach the ground. * Because of the continuing telemetry problems, the MOC is now putting out 4 rolling weeks of schedule, so that the instrument teams can plan for the track times. No non-routine events will appear in the two new additional planning weeks. * The PLASTIC team asks if the spacecraft can turn off specific APIDs to being written to the SSR. This question was asked both in regards to a possible autonomy rule when partitions reach capacity, and for the upcoming lower telemetry rates. These changes may not be possible in the DPU. PLASTIC will come up with a strawman plan for APL to consider. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 19: M May 10 (130) Both: 720 kbps downlink T May 11 (131) W May 12 (132) T May 13 (133) F May 14 (134) S May 15 (135) S May 16 (136) ------------------------------------------------------------------------------- Scheduled activities for Week 20: M May 17 (137) T May 18 (138) Ahead: SECCHI stepped calibration roll, 00:25 UT Ahead: Perihelion, 18:57 UT Behind: 31 hour gap between passes W May 19 (139) T May 20 (140) Ahead: 34 hour gap between passes F May 21 (141) Behind: 35.5 hour gap between passes S May 22 (142) S May 23 (143) Ahead: 720 kbps downlink on station 43 ------------------------------------------------------------------------------- Scheduled activities for Week 21: M May 24 (144) T May 25 (145) W May 26 (146) Ahead: SECCHI GT calibration offset, 9:25 UT T May 27 (147) F May 28 (148) S May 29 (149) S May 30 (150) Notes: * Commercial power will off at APL during Memorial Day weekend, May 28-31. The STEREO MOC will be operating on UPS and a generator. ------------------------------------------------------------------------------- Scheduled activities for Week 22: M May 31 (151) T Jun 01 (152) W Jun 02 (153) T Jun 03 (154) F Jun 04 (155) Ahead: Momentum dump, 14:00 UT S Jun 05 (156) S Jun 06 (157) Notes: * Commercial power will off at APL during Memorial Day weekend, May 28-31. The STEREO MOC will be operating on UPS and a generator. ------------------------------------------------------------------------------- Scheduled activities for Week 23: M Jun 07 (158) T Jun 08 (159) SUMI sounding rocket launch http://adsabs.harvard.edu/abs/2008AGUSMSP51B..01A W Jun 09 (160) Behind: Momentum dump, 21:30 UT T Jun 10 (161) 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) T Jun 17 (168) F Jun 18 (169) S Jun 19 (170) S Jun 20 (171) ------------------------------------------------------------------------------- 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