STEREO Weekly Meeting Minutes for 2011-06-21 (Week 25) ANNOUNCEMENTS ------------- * None INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 24 (Jun 13-19) * On day 165 (Jun 14), before the start of the return to service DSS 34 support for Ahead, the transmitter was declared red and remained unavailable for the duration. See DR# C108082 for more information. * On day 168 (Jun 17), during the DSS 45 support for Ahead, the MOC lost monitor data, telemetry, and commanding from 20:42-21:05z due to an external communications (JPL>CDSCC NTR1 & NTR2) failure at SPC-40. All SSR data were recovered. See DR# N107424 for more information. * On day 166 (Jun 15), a 160 kbps downlink rate test track with Ahead was conducted satisfactory using DSS 25. * On day 167 (Jun 16), a flight software load to the IMPACT IDPU on Ahead was conducted to upgrade the PLASTIC flight software to better control the APIDs returned. * The above flight software load was not to mitigate the recent anomaly in the LET. Instead, thresholds were rolled back. Plans for software changes to better monitor the instrument, or to skip over the suspected region of code, have been put on hold. * On day 168 (Jun 17), IMPACT executed a soft reset of the IDPU on Ahead to activate the new flight software loaded on DOY 167. * On day 169 (Jun 18), IMPACT and PLASTIC completed configuring their instruments after the IDPU soft reset on Ahead. IMPACT was actually recovered on day 168, PLASTIC on day 169. * On day 164 (Jun 13), during the DSS 63 support for Behind, turbo decoder lock was lost briefly beginning at 1655z. This resulted in the loss of four frames of instrument SSR data. See DR# N107413 for more information. * On day 165 (Jun 14), during the DSS 63 support for Behind, telemetry lock was intermittent beginning at 1632z for 12 minutes due the low elevation of the antenna and the sub-reflector in a fixed position. A stable telemetry lock was established at 1644z. Later in the support, turbo decoder lock was lost at 1916z. These anomalies resulted in the loss of five frames of instrument SSR data. See DR# M106365 and DR# N107428 for more information. * On day 167 (Jun 16), the transmitter was declared red before the start of the DSS 54 support for Behind. Later in the support, turbo decoder lock was lost briefly at 1818z and at 1851z. These anomalies resulted in no uplink for the duration of the support and the loss of seven frames of instrument SSR data. See DR# M106367 and DR# N107425 for more information. * On day 169 (Jun 18), during the DSS 55 support for Behind, the MOC lost monitor data and telemetry from 16:20-18:09z due to the Monitor Data Server 1 crash at SPC-60. All SSR data were recovered. See DR# M106372 for more information. * On day 170 (Jun 19), during the DSS 26 support for Behind, turbo decoder lock was lost briefly beginning at 0153z. This resulted in the loss of thirteen frames of instrument SSR data. See DR# N107429 for more information. * The average daily SSR playback volume was 6.4 gigabits for Ahead, and 6.2 gigabits for Behind. Week 25 (Jun 20-26) * Macros for the 160 and 120 kbps downlink rates were uploaded to RAM on Ahead this morning (Jun 21), and will be uploaded to Behind this afternoon. * Ahead has a 720 kbps pass on Friday, Jun 24, using station 43. There are 11 tracks during the week, and overall coverage is 2.1 hours above nominal. * Behind has a 720 kbps pass on Sunday, Jun 26, using station 63. There are 14 tracks during the week, and overall coverage is 8 hours above nominal. Week 26 (Jun 27-Jul 3) * Ahead switches downlink rate to 160 kbps on 34 meter stations, and 480 kbps on 70 meter stations on day 178 (Jun 27), starting with the station 15 pass at 15:40 UT. 480 kbps is the lowest rate that Ahead is projected to use with 70 meter stations--Behind will drop to 360 kbps for periods near the far side. * Modified macros for the 240 kbps rate will be uploaded to RAM on both spacecraft on Monday, day 178 (Jun 27) to take into account the increasing light travel time. These changes will downlink the spacecraft housekeeping data prior to the uplink sweep for each pass. Science playback time will continue to start at nearly the same time as it currently does. These changes will increase the science data return by about 20 minutes since the playback of spacecraft data is currently after the uplink sweep. * Ahead has 480 kbps passes on Thursday, Jun 30 (D63), and Sunday, Jul 3 (D43). There are 10 passes during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Monday, Jun 27, Wednesday, Jun 29, Thursday, Jun 30, Friday, Jul 1, and Saturday, Jul 2, all using station 63. There are 12 passes during the week, and overall coverage is nominal. Week 27 (Jul 4-10) * Monday, July 4 is a holiday, so if you need to command please contact the MOC ahead of time. * Switch over to Space Link Extension (SLE) protocol on Behind July 5 during DSS 63 track and on Ahead July 6 during DSS 14 track. Both the switches will take place during business hours. * Ahead has 480 kbps passes on Tuesday, Jul 5 (D63 and D14), Wednesday, Jul 6 (D63 and D14), Thursday, Jul 7 (D14), and Friday, Jul 8 (D63). There are 13 passes during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Tuesday, Jul 5 (D63), Friday, Jul 8 (D43), and Sunday, Jul 10 (D63). There are 12 passes during the week, and overall coverage is nominal. Week 28 (Jul 11-17) * Behind will switch to the 160 kbps rate for 34 meter stations, and 480 kbps for 70 meter stations, starting with the station 55 pass on Jul 13. * Both spacecraft will have an HGA calibration on Jul 13, with Ahead starting at 15:00 UT, and Behind starting at 16:00 UT. * Behind will have the 33rd momentum dump on Tuesday, Jul 12, starting at 19:30 UT. * Ahead will have the 39th momentum dump on Thursday, Jul 14, starting at 15:00 UT. * Ahead has 480 kbps passes on Tuesday, Jul 12, and Saturday, Jul 16, both using station 43. There are 10 passes during the week, and overall coverage is 3.6 hours above nominal. * Behind has 720 kbps passes on Tuesday, Jul 12 (D43 and D63), and 480 kbps passes on Thursday, Jul 14 (D43), Friday, Jul 15 (D43 and D63), and Sunday, Jul 17 (D43). There are 15 passes during the week, and overall coverage is 4.1 hours above nominal. Week 29 (Jul 18-24) * Ahead has 480 kbps passes on Monday, Jul 18, Tuesday, Jul 19, Wednesday, Jul 20, and Thursday, Jul 21, all using station 14. There are 8 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Thursday, Jul 21, Friday, Jul 22, and Saturday, Jul 23, all using station 63. There are 13 passes during the week, and overall coverage is 3 hours above nominal. Week 30 (Jul 25-31) * The 18th SECCHI stepped calibration roll on Ahead is scheduled for Tuesday, day 207 (Jul 26), starting at 7:15 UT. * Ahead has 480 kbps passes on Monday, Jul 25, Tuesday, Jul 26, and Wednesday, Jul 27, all using station 63. There are 13 passes during the week, and overall coverage is 1.6 hours above nominal. * Behind has 480 kbps passes on Friday, Jul 29, using stations 14 and 43. There are 14 passes during the week, and overall coverage is 3 hours above nominal. Other * APL is working on the script for the roll to observe Comet Elenin from Behind. They estimate that there will be 1 hour and 20 minutes of dwell time available during the 2 hour maneuver. A test run will be scheduled about two weeks before the start of the observations. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 25: M Jun 20 (171) T Jun 21 (172) W Jun 22 (173) T Jun 23 (174) F Jun 24 (175) Ahead: 720 kbps downlink on station 43 S Jun 25 (176) S Jun 26 (177) Behind: 720 kbps downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 26: M Jun 27 (178) Ahead: Switch downlink rate to 160 kbps, 480 kbps for 70 m Behind: 720 kbps downlink on station 63 T Jun 28 (179) W Jun 29 (180) Behind: 720 kbps downlink on station 63 T Jun 30 (181) Ahead: 480 kbps downlink on station 63 Behind: 720 kbps downlink on station 63 F Jul 01 (182) Behind: 720 kbps downlink on station 63 S Jul 02 (183) Behind: 720 kbps downlink on station 63 S Jul 03 (184) Ahead: 480 kbps downlink on station 43 ------------------------------------------------------------------------------- Scheduled activities for Week 27: M Jul 04 (185) Independence day T Jul 05 (186) Ahead: 480 kbps downlink on stations 63 and 14 Behind: 720 kbps downlink on station 63 W Jul 06 (187) Ahead: 480 kbps downlink on stations 63 and 14 T Jul 07 (188) Ahead: 480 kbps downlink on station 14 F Jul 08 (189) Ahead: 480 kbps downlink on station 63 Behind: 720 kbps downlink on station 43 S Jul 09 (190) S Jul 10 (191) Behind: 720 kbps downlink on station 63 ------------------------------------------------------------------------------- Scheduled activities for Week 28: M Jul 11 (192) T Jul 12 (193) Behind: Momentum dump, 19:30 UT Ahead: 480 kbps downlink on station 43 Behind: 720 kbps downlink on stations 43 and 63 W Jul 13 (194) Behind: Switch downlink rate to 160 kbps, 480 kbps for 70 m HGA calibration, Ahead: 15:00 UT, Behind: 16:00 UT T Jul 14 (195) Ahead: Momentum dump, 15:00 UT Behind: 480 kbps downlink on station 43 F Jul 15 (196) Behind: 480 kbps downlink on stations 43 and 63 S Jul 16 (197) Ahead: 480 kbps downlink on station 43 S Jul 17 (198) Behind: 480 kbps downlink on station 43 Notes: * Dawn expected to achieve orbit about Vesta around Jul 16. ------------------------------------------------------------------------------- Scheduled activities for Week 29: M Jul 18 (199) Ahead: 480 kbps downlink on station 14 T Jul 19 (200) Ahead: 480 kbps downlink on station 14 W Jul 20 (201) Ahead: 480 kbps downlink on station 14 T Jul 21 (202) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 63 F Jul 22 (203) Behind: 480 kbps downlink on station 63 S Jul 23 (204) Behind: 480 kbps downlink on station 63 S Jul 24 (205) Notes: * Test run of Comet Elenin roll to be tested on Behind during the week. ------------------------------------------------------------------------------- Scheduled activities for Week 30: M Jul 25 (206) Ahead: 480 kbps downlink on station 63 T Jul 26 (207) Ahead: SECCHI stepped calibration roll, 7:15 UT Ahead: 480 kbps downlink on station 63 W Jul 27 (208) Ahead: 480 kbps downlink on station 63 T Jul 28 (209) F Jul 29 (210) Behind: 480 kbps downlink on stations 14 and 43 S Jul 30 (211) S Jul 31 (212) ------------------------------------------------------------------------------- Upcoming events: 2011: * Jul 31 - Aug 12 Behind: Spacecraft rolls to observe comet Elenin 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