STEREO Weekly Meeting Minutes for 2016-12-13 (Week 50) ANNOUNCEMENTS ------------- * None INSTRUMENT and SPACECRAFT STATUS -------------------------------- * Ahead is operating nominally on the main lobe of the high gain antenna. * Attempts to recover Behind have transitioned back to a monthly schedule. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 49 (Dec 5-11) * On day 346 (Dec 11), during the DSS-63 support for Ahead, turbo decoder lock was lost briefly at 1329z. This anomaly resulted in the loss of 2 frames of SSR data. * On day 346 (Dec 11), during the DSS-26 support for Ahead, a project interface test was conducted to test DTT software version 12.3.2 (downlink tracking and telemetry upgrades). All test objectives were completed successfully. There was no SSR playback as this was not an operational track. * The average daily science data return for Ahead was 5.1 Gbits during this week. Week 50 (Dec 12-18) * The 37th SECCHI stepped calibration roll for perihelion was carried out this morning (Dec 13). This was the sixth roll without using the gyros. * Ahead has 9 tracks during the week, and overall coverage is nominal. There are six passes at 720 kbsp, two at 240 kbps, and one at 160 kbps. * Behind starts the week at an SPE angle of 15.0 degrees. Battery recovery passes are scheduled for Friday, Dec 16, using the 80 kW transmitter on station 26, and on Sunday, Dec 18, with station 43. Later on Sunday is a carrier recovery track with station 14. The DSN radio science receiver will be used during the 70 meter tracks. Week 51 (Dec 19-25) * The 94th momentum dump on Ahead is scheduled for 15:30 UT on Tuesday, Dec 20. This will be the 13th dump without using the gyros. * Sunday, Dec 25, is Christmas. Hanukkah runs from Dec 24 to Jan 1. * Ahead has 9 passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, two at 240 kbps, and one at 160 kbps. * Behind starts the week at an SPE angle of 15.3 degrees. There are no tracks for Behind during the week. Week 52 (Dec 26-Jan 1) * Monday, Dec 26, is a holiday at APL. * New Year's Day is Sunday, Jan 1. * A leap second will be added at the end of the UT day on Saturday, Dec 31. The leap second will be implemented onboard with time tagged commands. * The MOC will look into the status of the spacecraft clock SPICE kernel files for the added leap second. * Ahead has 11 passes during the week, and overall coverage is nominal. There are 9 tracks at 720 kbps, and two at 240 kbps. * Behind starts the week at an SPE angle of 15.7 degrees. There are no tracks for Behind during the week. Week 1 (Jan 2-8) * Monday, Jan 2, is the observed New Year holiday. * Ahead has 11 passes during the week, and overall coverage is nominal. There are five tracks at 720 kbps, one at 240 kbps, and five at 160 kbps. * There are no tracks for Behind during the week. Week 2 (Jan 9-15) * Ahead has 8 passes during the week, and overall coverage is nominal. There are seven passes at 720 kbps, and one at 240 kbps. * Behind has no passes during the week. Week 3 (Jan 16-22) * Monday, Jan 16, is Martin Luther King Day. This is a federal holiday, but APL will be open. * The 95th momentum dump on Ahead is scheduled for Thursday, Jan 19, with ignition at 21:00 UT. This will be the 14th dump without using the gyros. * Federal government offices in the DC area on Friday, Jan 20, for the presidential inauguration. * Ahead has 8 passes during the week, and overall coverage is nominal. There are five passes at 720 kbps, two at 240 kbps, and one at 160 kbps. * Battery recovery tracks are on Friday, Jan 20, with station 14, and on Saturday, Jan 21, with the 80 kW transmitter on station 26. A carrier recovery track will be carried out with station 14 on Sunday, Jan 22. The radio science receiver will be used with the station 14 tracks. Week 4 (Jan 23-29) * Ahead has 8 passes during the week. There is a slight shortage of 2 hours in coverage on Monday, Jan 23. This may result in some loss of in situ data. The MOC is looking into the possibility of additional coverage. The STEREO project does not yet have authorization to use ESA stations in 2017. There are currently five tracks at 720 kbps, one at 240 kbps, and two at 160 kbps. * Behind has no passes during the week. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 50: M Dec 12 (347) T Dec 13 (348) Ahead: SECCHI stepped calibration roll, 06:55 UT W Dec 14 (349) T Dec 15 (350) F Dec 16 (351) Behind: Battery recovery track with station 26 S Dec 17 (352) S Dec 18 (353) Behind: Battery recovery track with station 43 Behind: Carrier recovery track with station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 51: M Dec 19 (354) T Dec 20 (355) Ahead: Momentum dump, 15:30 UT W Dec 21 (356) T Dec 22 (357) F Dec 23 (358) S Dec 24 (359) S Dec 25 (360) Christmas ------------------------------------------------------------------------------- Scheduled activities for Week 52: M Dec 26 (361) Christmas holiday T Dec 27 (362) W Dec 28 (363) T Dec 29 (364) F Dec 30 (365) S Dec 31 (366) S Jan 01 (001) New Year ------------------------------------------------------------------------------- Scheduled activities for Week 01: M Jan 02 (002) New Year holiday T Jan 03 (003) W Jan 04 (004) T Jan 05 (005) F Jan 06 (006) S Jan 07 (007) S Jan 08 (008) ------------------------------------------------------------------------------- Scheduled activities for Week 02: M Jan 09 (009) T Jan 10 (010) W Jan 11 (011) T Jan 12 (012) F Jan 13 (013) S Jan 14 (014) S Jan 15 (015) ------------------------------------------------------------------------------- Scheduled activities for Week 03: M Jan 16 (016) Martin Luther King Day T Jan 17 (017) W Jan 18 (018) T Jan 19 (019) Ahead: Momentum dump, 21:00 UT F Jan 20 (020) Inauguration Day Behind: Battery recovery track with station 14 S Jan 21 (021) Behind: Battery recovery track with station 26 S Jan 22 (022) Behind: Carrier recovery track with station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 04: M Jan 23 (023) T Jan 24 (024) W Jan 25 (025) T Jan 26 (026) F Jan 27 (027) S Jan 28 (028) S Jan 29 (029) ------------------------------------------------------------------------------- Upcoming events: Behind events are contingent on recovering the spacecraft. 2016: * Dec Behind: Resume LGA downlink capability on 70 m DSN 2017: 2018: * Mar 5 Ahead: Mercury transit 2019: * Mar Ahead: Switch downlink rate to 240 kbps for 34 meter * Apr Behind: Switch downlink rate to 240 kbps for 34 meter 2020: * May Behind: Switch downlink rate to 360 kbps for 34 meter * Jun Ahead: Switch downlink rate to 360 kbps for 34 meter * Jun Behind: Switch downlink rate to 480 kbps for 34 meter * Sep Ahead: Switch downlink rate to 480 kbps for 34 meter 2021: * Jul Behind: Switch downlink rate to 720 kbps for 34 meter * Aug Ahead: Switch downlink rate to 720 kbps for 34 meter 2022: 2023: * May 5 Behind: Mercury transit * Jul 17 Behind: Closest approach to Earth * Aug 13 Ahead: Closest approach to Earth 2024: 2025: * Apr 7 Ahead: Mercury transit 2026: 2027: * Feb 1 Behind: Mercury transit 2028: 2029: * Jun 30 Ahead: Mercury transit