STEREO Weekly Meeting Minutes for 2010-12-07 (Week 49) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 48 * On day 334 (Nov 30), during the DSS 54 support for Ahead, no uplink was available for the duration of the support due to the transmitter being declared red. This resulted in the loss of all commanding and two-way tracking data. All SSR data were recovered. * Also on day 334 (Nov 30), during the DSS 24 support for Ahead, ranging lock was acquired late at 1237z due to an equipment anomaly. This resulted in the loss of 16 minutes of ranging data. All SSR data were recovered. See DR# G110807 for more information. * On day 336 (Dec 2), the DSN switched to using the new Data Capture and Delivery (DCD) data flow path at the Goldstone complex for DSS 15 only. This replaced the existing RNS and CDR data flow path. The remaining DSS at Goldstone will switchover next week, beginning on DOY 341 (Dec 7). * On day 336 (Dec 2), the 34th momentum dump on Ahead was successfully executed at 1500Z, which imparted a delta V of 0.091 m/sec. * On day 337 (Dec 3), the SECCHI instrument on Ahead reset at 17:31:27z. The SECCHI team reconfigured the instrument to operational mode at 1340z the next day (Dec 4). This was the 19th reset of SECCHI on the Ahead spacecraft. * The average daily SSR downlink was 4.9 gigabits for Ahead, and 4.7 gigabits for Behind. Week 49 * Telemetry lock was lost intermittently due to weather during the station 65 pass for Ahead yesterday (Dec 6), starting at 05:12 for about an hour. This is likely to lead to some data loss for all instruments. * STEREO-Ahead is currently up on station 43 (Dec 7). However, this station is currently needed by the Japanese Akatsuki (Planet C) mission because of a spacecraft emergency associated with their orbital insertion about Venus. STEREO will be able to get about 1 hour out of the planned 5 hours of coverage. Commands will be sent up to stop the playback, and options are being looked into for replacement support. The next scheduled pass is at 12:15 UT tomorrow. * Goldstone stations 24, 25, 26, and 14 will start using the new DCD system later today (Dec 7). * Ahead has a 720 kbps pass on Tuesday, Dec 7, using station 43, which is now being given over to Akatsuki. There are 14 passes during the week, and overall coverage would be nominal, except for the loss of station 43 time. * 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. Week 50 * The 28th momentum dump on Behind will be performed on Dec 15, with ignition at 17:30 UT. * 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. * 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 passes on either side are both 70 meter 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. Week 2 * The 13th HGA calibrations are scheduled for Behind on Wednesday, Jan 12, and for Ahead on Thursday, Jan 13, starting at 16:00 UT each day. These activities will last about an hour, and will involve rolls of 0.5 degrees. The track times have been extended to 7 hours, and SSR downlink will be stopped during the calibration. * Ahead has a 720 kbps pass on Monday, Jan 10, using station 43. There are 13 tracks during the week, and overall coverage is nominal. * Behind has a 720 kbps pass on Friday, Jan 14, using station 14. There are 14 tracks during the week, and overall coverage is 4.6 hours over nominal. Other * There was some discussion about conflicts with other missions. Behind was earlier in a lot of contentions with missions, but the situation is now improved. The main contentions for Behind are with Kepler and SIRTF (Spitzer), and to a lesser extent with Cassini. However, Ahead will be facing contentions with many missions over the next 6-8 months. * The problem that the Madrid station was having with DCD files was discussed. The problem occurred when the DCD failed over to the redundant side. This resulted in some files not being transferred to APL. JPL is aware of the problem, and the MOC will monitor what files it recieves. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- 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) ------------------------------------------------------------------------------- Scheduled activities for Week 02: M Jan 10 (010) Ahead: 720 kbps downlink on station 43 T Jan 11 (011) W Jan 12 (012) Behind: HGA calibration, 16:00 UT T Jan 13 (013) Ahead: HGA calibration, 16:00 UT F Jan 14 (014) Behind: 720 kbps downlink on station 14 S Jan 15 (015) S Jan 16 (016) ------------------------------------------------------------------------------- Upcoming events: 2011: * 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