STEREO Weekly Meeting Minutes for 2011-07-26 (Week 30) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * On day 199 (Jul 18), the scheduled space weather broadcast from BEHIND only was changed to end early by 25 minutes, from 0625 UTC to 0600 UTC, to provide a test downlink of the current 160 kbps, turbo rate 1/6, rate to the ESA New Norcia station in support of the upcoming NASA/ESA mission Exomars. The station successfully locked to the downlink. * On day 203 (Jul 22), a test of the SECCI HI 135 degree roll event, which will be used August on BEHIND only to observe Comet Elenin, was executed successfully on the BEHIND observatory. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 29 (Jul 18-24) * On day 200 (Jul 19), during the DSS 45 support for Behind, turbo decoder lock was lost briefly beginning at 0538z. This resulted in the loss of 1 frame of SSR data. See DR# N107492 for more information. * A test was conducted yesterday (Jul 19) using Behind with the ESA New Norcia station in western Australia. The test was conducted at the normal mode of 160 kbps, with Turbo 1/6 encoding. A previous test at 360 kbps with Turbo 1/4 encoding proved to be too weak. However, this test went well, and was consistent with a concurrent Canberra track. * On day 201 (Jul 20), during the DSS 24 support for Behind, turbo decoder lock was lost briefly beginning at 0221z. This resulted in the loss of 1 frame of SSR data. See DR# N107496 for more information. * On day 202 (Jul 21), for the DSS 14 support for Ahead, the transmitter was declared red prior to track due to a a body flow interlock problem. This anomaly resulted in the loss of all commanding and two-way tracking data for the duration of support. See DR# G111807 for more information. * On day 205 (Jul 24), during the DSS 25 support for Ahead, turbo decoder lock was lost briefly beginning at 1802z. This resulted in the loss of 1 frame of SSR data. A DR has been requested. * 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 nominal. * The average daily SSR playback volume was 5.7 gigabits for Ahead, and 4.9 gigabits for Behind. Week 30 (Jul 25-31) * On day 206 (Jul 25), during the DSS 63 support for Ahead, at 03:20 UT a signal could not be captured resulting in a 26 minute delay. This had no impact. * On day 207 (Jul 26), during the DSS 63 support for Ahead, at 03:20UT turbo decoder lock was lost briefly. This resulted in the loss of 9 frames of SSR data. * The 18th SECCHI stepped calibration roll on Ahead is scheduled for Tuesday, day 207 (Jul 26), starting at 7:15 UT. This is the midpoint roll, and lasts about 3 hours. System momentum is expected to be about 7 N-m-s. * The SECCHI stepped calibration roll on Behind has been moved ahead a week, because of the comet Elenin observations, and is also scheduled for Jul 26, starting at 9:00 UT. This is also the midpoint roll. System momentum is expected to be about 4 N-m-s. * There have been several changes to the DSN schedule for Ahead during the week, due to support needed for another mission. Two 34 meter stations on Jul 31 were swapped for a 70 meter support. Ahead has 480 kbps passes on Monday, Jul 25 (D63), Tuesday, Jul 26 (D63), Wednesday, Jul 27 (D63), and Sunday, Jul 31 (D14). There are 12 passes during the week, and overall coverage is 1.5 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 6.5 hours above nominal. Week 31 (Aug 1-7) * The launch window for JUNO opens at 15:26 on Aug 5. This is the first of several upcoming launches that will impact the STEREO schedule. If JUNO doesn't launch the first day, the Ahead pass on Saturday, Aug 6, may be reduced by 50 minutes. * The 135 degree rolls on Behind to observe comet Elenin will start on Aug 1. The rolls will be between 8-10 UT each day, except for Aug 5 and Aug 12, when the rolls will be between 10-12 UT. * Ahead has 480 kbps passes on Monday, Aug 1 (D14), Tuesday, Aug 2 (D14), Wednesday, Aug 3 (D63), and Thursday, Aug 4 (D43). There are 9 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Thursday, Aug 4 (D14), and Friday, Aug 5 (D43). There are 13 passes during the week, and overall coverage is nominal. Week 32 (Aug 8-14) * The 135 degree rolls on Behind to observe comet Elenin will continue through Aug 12. The rolls will be between 8-10 UT each, except for Aug 12, when the roll will be between 10-12 UT. * Ahead has 480 kbps passes on Friday, Aug 12 (D14), Saturday, Aug 13 (D63), and Sunday, Aug 14 (D14). There are 10 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Tuesday, Aug 9 (D14 and D63), and Thursday, Aug 11 (D63). There are 14 passes during the week, and overall coverage is nominal. Week 33 (Aug 15-21) * The MOC network will be refreshed between 15-23 UT on Monday, Aug 15. This will be between passes, and will not affect operations. * The external network switch at APL will be upgraded on Wednesday, Aug 17, at 03:35 UT. This will also be between tracks. * Ahead has 480 kbps passes on Monday, Aug 15 (D63), Tuesday, Aug 16 (D14), Wednesday, Aug 17 (D14), Thursday, Aug 18 (D14), and Friday, Aug 19 (D14) There are 8 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Tuesday, Aug 16, twice on Friday, Aug 19, and Sunday, Aug 21, all using station 14. There are 15 passes during the week, and overall coverage is 8.1 hours above nominal. Week 34 (Aug 22-28) * The 40th momentum dump on Ahead is scheduled for Wednesday, Aug 24, starting at 15:00 UT. * The 35th momentum dump on Behind is also scheduled for Wednesday, Aug 24, starting at 18:00 UT. * Ahead has 480 kbps passes on Monday, Aug 22 (D63), Wednesday, Aug 24 (D14), Friday, Aug 26 (D63), Saturday, Aug 27 (D14), and Sunday, Aug 28 (D14). There are 11 passes during the week, and overall coverage is nominal. * Behind has a 480 kbps pass on Monday, Aug 22 using station 43. There are 14 passes during the week, and overall coverage is 5.6 hours above nominal. Week 35 (Aug 29-Sep 4) * Ahead has 480 kbps passes on Monday, Aug 29 (D63), Tuesday, Aug 30 (D14), Wednesday, Aug 31 (D63), Thursday, Sep 1 (D14), Friday, Sep 2 (D14), and Sunday, Sep 4 (D14). There are 11 passes during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Monday, Aug 29 (D43), Wednesday, Aug 31 (D14), and Thursday, Sep 1 (D63). There are 13 passes during the week, and overall coverage is 1.3 hours above nominal. Week 36 (Sep 5-11) * Monday, Sep 5 is Labor Day. APL will be closed for the holiday. * Thursday, Sep 8 is the opening of the launch window for the GRAIL mission This is a very intense mission, lasting just 9 months, and will require a lot of track time. This will affect the DSN scheduling for STEREO. The project is looking into getting support from ESA stations to cover the shortfall. * Ahead has 480 kbps passes on Tuesday, Sep 6 (D14), Thursday, Sep 8 (D43), and Friday, Sep 9 (D63 and D14). There are 11 tracks during the week, and overall coverage is nominal. * Behind has 480 kbps passes on Monday, Sep 5 (D43), Wednesday, Sep 7 (D43), and Saturday, Sep 10 (D63). There are 14 tracks during the week, and overall coverage is nominal. Week 37 (Sep 12-18) * There is only 6 hours of coverage on Friday, Sep 16. The in situ instruments should probably be okay, but SECCHI should reduce their schedule. The following pass on Saturday is a 70 meter station. * There is a gap of 19 days in coverage from southern hemisphere stations for the Ahead spacecraft starting in week 37. This will affect the accuracy of the ephemeris calculations. Use of the ESA New Norcia station would mitigate this problem. * Ahead has 480 kbps passes on Monday, Sep 12 (D14), Tuesday, Sep 13 (D63), Wednesday, Sep 14 (D14), Thursday, Sep 15 (D63), and Saturday, Sep 17 (D63). There are 10 passes during the week, and overall coverage is below nominal, particularly for Friday. Similar situations are expected for the next several weeks. * Behind has 480 kbps passes on Monday, Sep 12 (D43 and D63), Tuesday, Sep 13 (D63), Wednesday, Sep 14 (D63), Thursday, Sep 15 (D63), Friday, Sep 16 (D43), Saturday, Sep 17 (D14), and Sunday, Sep 18 (D63). There are 10 passes during the week, and overall coverage is nominal. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- 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 Behind: SECCHI stepped calibration roll, 9:00 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) Ahead: 480 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 31: M Aug 01 (213) Behind: 135 degree roll to observe comet Elenin, 8-10 UT Ahead: 480 kbps downlink on station 14 T Aug 02 (214) Behind: 135 degree roll to observe comet Elenin, 8-10 UT Ahead: 480 kbps downlink on station 14 W Aug 03 (215) Behind: 135 degree roll to observe comet Elenin, 8-10 UT Ahead: 480 kbps downlink on station 63 T Aug 04 (216) Behind: 135 degree roll to observe comet Elenin, 8-10 UT Ahead: 480 kbps downlink on station 43 Behind: 480 kbps downlink on station 14 F Aug 05 (217) Behind: 135 degree roll to observe comet Elenin, 10-12 UT Behind: 480 kbps downlink on station 43 S Aug 06 (218) Behind: 135 degree roll to observe comet Elenin, 8-10 UT S Aug 07 (219) Behind: 135 degree roll to observe comet Elenin, 8-10 UT Notes * Aug 1-12 Behind: Spacecraft rolls to observe comet Elenin ------------------------------------------------------------------------------- Scheduled activities for Week 32: M Aug 08 (220) Behind: 135 degree roll to observe comet Elenin, 8-10 UT T Aug 09 (221) Behind: 135 degree roll to observe comet Elenin, 8-10 UT Behind: 480 kbps downlink on stations 14 and 63 W Aug 10 (222) Behind: 135 degree roll to observe comet Elenin, 8-10 UT T Aug 11 (223) Behind: 135 degree roll to observe comet Elenin, 8-10 UT Behind: 480 kbps downlink on station 63 F Aug 12 (224) Behind: 135 degree roll to observe comet Elenin, 10-12 UT Ahead: 480 kbps downlink on station 14 S Aug 13 (225) Ahead: 480 kbps downlink on station 63 S Aug 14 (226) Ahead: 480 kbps downlink on station 14 Notes * Aug 1-12 Behind: Spacecraft rolls to observe comet Elenin ------------------------------------------------------------------------------- Scheduled activities for Week 33: M Aug 15 (227) Ahead: 480 kbps downlink on station 63 T Aug 16 (228) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 14 W Aug 17 (229) Ahead: 480 kbps downlink on station 14 T Aug 18 (230) Ahead: 480 kbps downlink on station 14 F Aug 19 (231) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 14 (twice) S Aug 20 (232) S Aug 21 (233) Behind: 480 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 34: M Aug 22 (234) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 43 T Aug 23 (235) W Aug 24 (236) Momentum dumps, Ahead: 15:00 UT, Behind: 18:00 UT Ahead: 480 kbps downlink on station 14 T Aug 25 (237) F Aug 26 (238) Ahead: 480 kbps downlink on station 63 S Aug 27 (239) Ahead: 480 kbps downlink on station 14 S Aug 28 (240) Ahead: 480 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 35: M Aug 29 (241) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 43 T Aug 30 (242) Ahead: 480 kbps downlink on station 14 W Aug 31 (243) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 14 T Sep 01 (244) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 63 F Sep 02 (245) Ahead: 480 kbps downlink on station 14 S Sep 03 (246) S Sep 04 (247) Ahead: 480 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 36: M Sep 05 (248) Behind: 480 kbps downlink on station 43 T Sep 06 (249) Ahead: 480 kbps downlink on station 14 W Sep 07 (250) Behind: 480 kbps downlink on station 43 T Sep 08 (251) Ahead: 480 kbps downlink on station 43 F Sep 09 (252) Ahead: 480 kbps downlink on stations 63 and 14 S Sep 10 (253) Behind: 480 kbps downlink on station 63 S Sep 11 (254) ------------------------------------------------------------------------------- Scheduled activities for Week 37: M Sep 12 (255) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on stations 43 and 63 T Sep 13 (256) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 63 W Sep 14 (257) Ahead: 480 kbps downlink on station 14 Behind: 480 kbps downlink on station 63 T Sep 15 (258) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 63 F Sep 16 (259) Behind: 480 kbps downlink on station 43 S Sep 17 (260) Ahead: 480 kbps downlink on station 63 Behind: 480 kbps downlink on station 14 S Sep 18 (261) Behind: 480 kbps downlink on station 63 ------------------------------------------------------------------------------- Upcoming events: 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