STEREO Weekly Meeting Minutes for 2016-11-22 (Week 47) 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 46 (Nov 14-20) * On day 319 (Nov 14), during the DSS-25 support for Ahead, in parallel with the operational track, a DSN PIT was conducted using the backup command workstation to test the TTC Software v1.3 for SLE Return Services. The backup workstation was connected to the test SLE server at the DSN. Real-time telemetry and monitor data were identical between the SLE test server and the operational server. * On day 323 (Nov 18), during the DSS-55 support for Ahead, the MOC received real-time telemetry at 1022z 37 minutes late due to a DCD issue. Also, the uplink sweep was 29 minutes late due to transmitter interlock anomaly. These anomalies resulted in the loss of 29 minutes of commanding and two-way tracking data and 56 frames of SSR data and 85 frames of real-time telemetry. See DR# M109662 and M109663 for more information. * On day 319 (Nov 14), at 1342z, MOps macro release 1.1.30 was loaded to C&DH EEPROM on Ahead and verified. This release updates, via macro 0, the post system reset RF configuration to the -Z LGA/HGA/+Z LGA each for 24 hours maintaining the emergency data rates throughout. * On day 321 (Nov 16), the 93rd momentum dump on Ahead was executed successfully at 1430z, which imparted an estimated delta V of 0.104 m/sec. This was the 12th momentum dump that did not use the IMU. After thruster operations completed, pointing performance was poor for the next 21 hours through ~322-1134z due to wheel 3 running along the zero-speed avoidance band but with its speed decreasing between avoidance computation updates. The performance improved dramatically after 322-1134z because wheel 3 changed spin directions and moved away from zero speed bands. * On day 322 (Nov 17), the SECCHI team conducted real-time commanding to investigate a COR1 zone1 internal autonomy rule. Nominal science operations resumed by 2000z. The rule will be re-enabled when an updated autonomy table is loaded. COR1 operations were suspended by the firing of the rule, and between that time and when COR1 was re-enabled at 2000z, the onboard SECCHI scheduler was confused by the lack of COR1 images, resulting in a number of misprocessed images from the other telescopes. * The SECCHI team asked whether there was any correlation between the resumption of normal SECCHI operations and the resumption of fine pointing. However, fine pointing was resumed some hours before the COR1 telescope was re-enabled, so there was no correlation. * The average daily science data return for Ahead was 4.4 Gbits during this week. * The status of Behind is unchanged. The next recovery attempt for Behind is on Dec 16. A report is underway describing the recovery operations for Behind earlier this year. There will also be an assessment review for that recovery attempt. Week 47 (Nov 21-27) * Thursday, Nov 24, is Thanksgiving. Both Thursday and Friday are holidays at APL. * Ahead has 13 passes during the week. Three ESA New Norcia passes were added on Monday and Tuesday to make up for the previous shortage, and overall coverage is now nominal. There are four tracks scheduled at 720 kbps, three at 240 kbps, and six at 160 kbps. * Behind starts the week at an SPE angle of 14.1 degrees. There are currently no passes scheduled for Behind during the week. * The current agreement for using ESA stations with STEREO expires at the end of the year. The MOC is looking into extending that agreement for another year. It is expected that there will be some unused hours to carry over. Week 48 (Nov 28-Dec 4) * Ahead has 10 passes during the week, and overall coverage is now nominal. Two ESA New Norcia passes have been added to the schedule. There are now four passes at 720 kbps, three at 240 kbps, and three at 160 kbps. * Behind starts the week at an SPE angle of 14.4 degrees. There are no tracks for Behind scheduled during the week. Week 49 (Dec 5-11) * There's a 2 hour project interface test with station 26 on day 346 (Dec 11) to test out new DTT software. There will be no SSR playback or instrument commanding during this track. * Ahead has 9 passes during the week, and overall coverage is nominal. There are five passes at 720 kbps, two at 240 kbps, and two at 160 kbps. A 3 hour ESA Malargue pass was added on Wednesday, Dec 7. * Behind starts the week at an SPE angle of 14.6 degrees. The previously scheduled recovery tracks have been moved to the following week to assist the Juno mission with planned perijove maneuvers. Week 50 (Dec 12-18) * The 37th SECCHI stepped calibration roll is scheduled for Tuesday, Dec 13, starting at 06:55 UT. This will be the perihelion roll. System momentum is expected to be 6 N-m-s. This will be 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. 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. Spacecraft clock SPICE kernel files will be available shortly. The leap second will be implemented onboard with time tagged commands. * 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 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. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 47: M Nov 21 (326) T Nov 22 (327) W Nov 23 (328) T Nov 24 (329) Thanksgiving F Nov 25 (330) S Nov 26 (331) S Nov 27 (332) ------------------------------------------------------------------------------- Scheduled activities for Week 48: M Nov 28 (333) T Nov 29 (334) W Nov 30 (335) T Dec 01 (336) F Dec 02 (337) S Dec 03 (338) S Dec 04 (339) ------------------------------------------------------------------------------- Scheduled activities for Week 49: M Dec 05 (340) T Dec 06 (341) W Dec 07 (342) T Dec 08 (343) F Dec 09 (344) S Dec 10 (345) S Dec 11 (346) Ahead: Project interface test with station 26 ------------------------------------------------------------------------------- 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) ------------------------------------------------------------------------------- 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