STEREO Weekly Meeting Minutes for 2010-11-30 (Week 48) ANNOUNCEMENTS ------------- * The STEREO Science Center was moved to a new location within Goddard. See below for details. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 47 * On day 326 (Nov 22), during the DSS 54 support for Ahead, command bind was lost at 0606z due to a transmitter exciter anomaly. Several other exciter anomalies on station 54 were seen during the week. The MOC rebound the command link at 0633z. It was not necessary to resweep the uplink. All planned commands were sent satisfactory. See DR# N106770 for more information. * On day 326 (Nov 22), during the DSS 14 support for Ahead, no ranging was available due to an equipment anomaly. The ranging anomaly also resulted in a late BOT at 1303z, resulting in the loss of some G&C telemetry. At 1416z through 1503z turbo decoder lock was lost intermittently at the 70 meter station due to weather. These anomalies resulted in the loss of an hour of instrument SSR data. See DR# G110782, G110783, and N106773 for more information. * On day 328 (Nov 24), during the DSS 24 support for Ahead, the antenna controller reset at 1359z. The downlink and uplink were re-established and SSR pointers were repositioned to maintain data continuity at 1435z. All SSR data were recovered. See DR# G110792 and G110793 for more information. * On day 329 (Nov 25), during the DSS 15 support for Ahead, turbo decoder lock was lost intermittently at 1219z through 1221z. This was soon after the sweep. All SSR data were recovered. See DR# N106777 for more information. * On day 326 (Nov 22), IMPACT LET real-time commanding was conducted on both spacecraft. * On day 327 (Nov 23), during the DSS 15 support for Behind which continued through the next day, turbo decoder lock was lost intermittently at 328-0031z through 0032z. This resulted in the loss of several minutes of instrument SSR data. A DR has been requested. * On day 329 (Nov 25), during the DSS 54 support for Behind, command bind was lost at 1817z due to a transmitter exciter anomaly. The MOC rebound the command link at 1838z. All planned commands were sent satisfactory. A DR has been requested. * On day 330 (Nov 26), during the DSS 26 support for Behind, turbo decoder lock was lost briefly at 0200z. This resulted in the loss of several minutes of instrument SSR data. A DR has been requested. * On day 331 (Nov 27), during the DSS 54 support for Behind, command bind was lost at 1554z due to a transmitter exciter anomaly. The MOC rebound the command link at 1837z. All planned commands were sent satisfactory. See DR# M106061 for more information. * The average daily SSR downlink was 5.3 gigabits for Ahead, and 5.0 gigabits for Behind. * During the previous week, a data gap was seen in the SECCHI data on day 321 (Nov 17), and in the data for the other instruments. This was originally thought to be due to low coverage, but has since been determined to be a problem with the new DCD system. Two IDR files were not delivered. APL has noted some other gaps during the week. The new DCD system is about to go into effect at Goldstone. The attitude history file should be okay, and the converted spacecraft housekeeping file shows no discontinuity. This is because the spacecraft telemetry comes down at the beginning of the track, at a different time than the instrument telemetry. The spacecraft telemetry also comes down again slowly during the rest of the track. DCD usage started during the previous week, on day 314 (Nov 10). Week 48 * The 34th momentum dump on Ahead will be carried out Thursday, Dec 2, with ignition at 15:00 UT. * Goldstone will start using the new DCD system for STEREO tomorrow on stations 15 and 24. The remaining Goldstone stations will use the DCD system for STEREO starting next Tuesday. * New C&DH macros were loaded this morning to both spacecraft to enable the autonomy rule for clearing space when the buffers are full for all rates. Previously, the autonomy rule was only enabled for the lower rates. * No uplink was available for the Ahead pass on station 54 this morning (Nov 30). The planned SECCHI and SWAVES commands were delayed, and went up on the later station 24 pass. * Ahead has 720 kbps passes on Monday, Nov 29, Wednesday, Dec 1, Thursday, Dec 2, and Saturday, Dec 4. The Monday pass uses station 14; the rest use station 63. There are 14 tracks during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Friday Dec. 3 and Sunday, Dec 5, using station 63. There are 13 tracks during the week, and overall coverage is 2 hours below nominal. * There will be a test track using station 25 on Behind on Dec 1, shadowing the track on station 26. Week 49 * Goldstone stations 25, 26, and 14 will start using the new DCD system for STEREO on Tuesday, Dec 7. * Ahead has a 720 kbps pass on Tuesday, Dec 7, using station 43. There are 14 passes during the week, and overall coverage is nominal. * Behind has a 720 kbps pass on Wednesday, Dec 8, using station 63. There are 11 passes during the week, and overall coverage is 1.8 hours above nominal. * There is a 32 hour gap between Behind passes Thursday to Friday (Dec 9-10). This will be close for the in situ instruments. Because of the 70 meter pass on Dec 8, the buffers should start out empty. Week 50 * An additional SECCHI stepped calibration roll for Ahead has been scheduled for Dec 16, starting at 13:20 UT. This is to take care of a change in the COR1-A background. The system momentum is expected to be about 6 N-m-s. * The 28th momentum dump on Behind will be performed on Dec 15, with ignition at 17:30 UT. * Ahead has 720 kbps passes on Monday, Dec 13, using station 43, on Thursday, Dec 16, using station 43, and on Saturday, Dec 18, using station 63. There are 13 passes during the week, and overall coverage is nominal. * Behind has a 720 kbps pass on Wednesday, Dec 15, using station 63. There are 11 passes during the week, and overall coverage is nominal. Week 51 * Christmas is on Saturday, Dec 25. Friday, Dec 24 is a holiday at APL. * Ahead has 720 kbps passes on Monday Dec 20 (D43), Wednesday, Dec 22 (D43), and Saturday, Dec 25 (D43). There are 14 passes during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Monday, Dec 20 (D63), Tuesday, Dec 21 (D63), Thursday, Dec 23 (D14), and Saturday, Dec 25 (D43). There are 10 passes during the week, and overall coverage is 3.2 hours below nominal. * There is only a short 3.8 hour track for Behind on Wednesday, Dec 22. The in situ instruments may come close to filling the SSR buffers. * The DSN schedule should accommodate the Christmas schedules for the stations. Week 52 * New Year's Day is on Saturday, Jan 1. Friday, Dec 31 is a holiday at APL. * Ahead has a 720 kbps pass on Wednesday, Dec 29 using station 43. There are 14 passes during the week, and overall coverage is nominal. * Behind has a 720 kbps pass on Friday, Dec 31, using station 43. There are 12 passes during the week, and overall coverage is 1.75 hours above nominal. Week 1 * Ahead has two 720 kbps passes on Wednesday, Jan 5 using stations 14 and 43. There are 14 passes during the week, and overall coverage is nominal * Behind has 720 kbps passes on Monday, Jan 3 (D63), Tuesday, Jan 4 (D43), Wednesday, Jan 5 (D63), Thursday, Jan 6 (D63), and Friday, Jan 7 (D63). There are 14 passes during the week, and overall coverage is 2 hours over nominal. Other * The STEREO Science Center was moved yesterday (Nov 29) to its new location in building 21 at Goddard. The SSC is now back up and running, but a problem remains with the connectivity between the SSC and APL. Please inform Bill Thompson of any other problems seen with the SSC after the move. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 48: M Nov 29 (333) Ahead: 720 kbps downlink on station 14 T Nov 30 (334) W Dec 01 (335) Ahead: 720 kbps downlink on station 63 Behind: Shadow track on station 25 T Dec 02 (336) Ahead: Momentum dump, 15:00 UT Ahead: 720 kbps downlink on station 63 F Dec 03 (337) Behind: 720 kbps downlink on station 63 S Dec 04 (338) Ahead: 720 kbps downlink on station 63 S Dec 05 (339) Behind: 720 kbps downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 49: M Dec 06 (340) T Dec 07 (341) Ahead: 720 kbps downlink on station 43 W Dec 08 (342) Behind: 720 kpbs downlink on station 63 T Dec 09 (343) F Dec 10 (344) S Dec 11 (345) S Dec 12 (346) ------------------------------------------------------------------------------- Scheduled activities for Week 50: M Dec 13 (347) Ahead: 720 kbps downlink on station 43 T Dec 14 (348) W Dec 15 (349) Behind: Momentum dump, 17:30 UT Behind: 720 kpbs downlink on station 63 T Dec 16 (350) Ahead: SECCHI calibration roll, 13:20 UT Ahead: 720 kbps downlink on station 43 F Dec 17 (351) S Dec 18 (352) Ahead: 720 kbps downlink on station 63 S Dec 19 (353) ------------------------------------------------------------------------------- Scheduled activities for Week 51: M Dec 20 (354) Ahead: 720 kbps downlink on station 43 Behind: 720 kpbs downlink on station 63 T Dec 21 (355) Behind: 720 kpbs downlink on station 63 W Dec 22 (356) Ahead: 720 kbps downlink on station 43 T Dec 23 (357) Behind: 720 kpbs downlink on station 14 F Dec 24 (358) S Dec 25 (359) Christmas Ahead: 720 kbps downlink on station 43 Behind: 720 kpbs downlink on station 43 S Dec 26 (360) Notes: * APL will be closed on Dec 24 ------------------------------------------------------------------------------- Scheduled activities for Week 52: M Dec 27 (361) T Dec 28 (362) W Dec 29 (363) Ahead: 720 kbps downlink on station 43 T Dec 30 (364) F Dec 31 (365) Behind: 720 kpbs downlink on station 43 S Jan 01 (001) New Years S Jan 02 (002) Notes: * APL will be closed on Dec 31 ------------------------------------------------------------------------------- Scheduled activities for Week 01: M Jan 03 (003) Behind: 720 kpbs downlink on station 63 T Jan 04 (004) Behind: 720 kpbs downlink on station 43 W Jan 05 (005) Ahead: 720 kbps downlink on both stations 14 and 43 Behind: 720 kpbs downlink on station 63 T Jan 06 (006) Behind: 720 kpbs downlink on station 63 F Jan 07 (007) Behind: 720 kpbs downlink on station 63 S Jan 08 (008) S Jan 09 (009) ------------------------------------------------------------------------------- Upcoming events: 2011: * Jan 12 Both: HGA calibration * Feb 6 STEREO spacecraft at 180 degree separation * Jun 27 Ahead: Switch downlink rate to 160 kbps * Jun 27 Ahead: End use of 720 kbps on 70 m DSN subnet * Jul 15 Behind: Switch downlink rate to 160 kbps * Jul 15 Behind: End use of 720 kbps on 70 m DSN subnet * Mar 18 Messenger - Mercury orbital insertion * Jul DAWN - Vesta arrival * Jul 13 Both: HGA calibration 2012: * Jan 11 Both: HGA calibration * Jul DAWN - Vesta departure * Jul 11 Both: HGA calibration * Nov 4 Behind: Switch downlink rate to 120 kbps * Nov 13 Total solar eclipse, south Pacific 2013: * May 3 Ahead: Switch downlink rate to 120 kbps * Dec 12 Ahead: Mercury transit 2014: * Jan 20 Behind: End use of 480 kbps on 70 m DSN subnet * Apr 21 Behind: Resume use of 480 kbps on 70 m DSN subnet * Apr 29 Behind: Mercury transit * Oct 15 Behind: End use of 480 kbps on 70 m DSN subnet 2015: * Feb DAWN - Ceres arrival * Jan 20 - Mar 28 (TBC) Behind: Spacecraft behind Sun * Mar 17 - Jul 14 (TBC) Ahead: Spacecraft behind Sun * Jul 2 Behind: Resume use of 480 kbps on 70 m DSN subnet * Aug 25 - Oct 19 (TBC) Behind: Spacecraft behind Sun * Sep 25 Behind: End use of 480 kbps on 70 m DSN subnet * Jul DAWN - End of nominal mission 2016: * Apr 3 Behind: Resume use of 480 kbps on 70 m DSN subnet 2017: * Jul 11 Ahead: Switch downlink rate to 160 kbps * Jul 22 Behind: Switch downlink rate to 160 kbps 2018: * Mar 5 Ahead: Mercury transit