STEREO Weekly Meeting Minutes for 2017-01-10 (Week 2) 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 1 (Jan 2-8) * On day 002 (Jan 2), during the DSS-14 support, turbo decoder lock was lost intermittently beginning at 1711z through 1737z due to weather. This anomaly resulted in the loss of 16,382 frames of SSR data or 3.4 minutes of SSR playback data for each instrument. See DR#N110429 for more information. * On day 003 (Tuesday, Jan 3), during the DSS-25 support, real-time data was lost between 1715z and1717z due to a delayed failover from the Data Capture and Delivery system (DCD1) to DCD2 at the DSN. All SSR data was recovered. See DR#G117717 for more information. * On day 004 (Wednesday, Jan 4), the primary Ahead command workstation in the MOC failed due to a hard disk failure at 0030z. The MOC switched to the backup command workstation at 0050z. The use of the backup command workstation required some reconfiguration for instrument teams to continue receiving real-time telemetry as a different real-time stream, #107, is being used. A replacement hard disk should arrive this week. * On day 004, during the DSS-43 support, turbo decoder lock was lost intermittently between 0920z and 0930z. This anomaly resulted in the loss of 2481 frames of SSR data. See DR #N110441 for more information. * On day 005 (Thursday, Jan 5), the MOC received notification from the DSN that the leap second was applied late, on day 004, at Goldstone. This affected the first three days of tracking data, telemetry data, and timekeeping processing. The DSN is correcting the tracking data for Navigation. Specifically for the telemetry data, the ground receipt time in the header of each packet in the level zero data is off by one second. Note that the spacecraft time in each packet is correct. The science teams indicated that this error did not affect science data processing or analysis. The impact to the timekeeping processing was that 5 days of the timekeeping history data product were not produced. The correction was applied to Goldstone data on 18:45 UT on Day 4. * On day 006 (Friday, Jan 6), automated retrieval of DSN schedules and view periods stopped due to an SPS hardware upgrade. DSN schedules are being retrieved manually until the SPS issue is resolved. * On day 008 (Sunday, Jan 8), during the DSS-63 support, turbo decoder lock was lost briefly at 1015z. This anomaly resulted in the loss of 19 frames of SSR data. * The average daily science data return for Ahead was 4.8 Gbits during this week. * There were no tracks for Behind during the week. The next recovery attempts for Behind are on Jan 20-22. * Comment: It looks like DSN transition to "Follow the Sun Operations" involves outages (~15 hours) that might affect us. DSN: STEREO should not be too greatly affected because its just needs the four hour 70 meter each day. We should at least have a health and safety track. She will check. Week 2 (Jan 9-15) * Ahead has 9 passes during the week, and overall coverage is nominal. There are eight 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 will be closed 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 9 passes during the week, and overall coverage is now nominal. An additional pass with station 63 was added on Tuesday. There are currently six tracks at 720 kbps, one at 240 kbps, and two at 160 kbps. * Behind has no passes during the week. Week 5 (Jan 30-Feb 5) * Ahead has 12 tracks during the week, and overall coverage is nominal. There are five passes at 720 kbps, one at 360 kbps, three at 240 kbps, and three at 160 kbps. Two ESA Malargue passes were added for Jan 30,31. * Behind has no passes during the week. Week 6 (Feb 6-12) * A 1.6 hour project interface test with Ahead using station 26 is scheduled for Sunday, Feb 12. There will be no SSR playback or instrument commanding during this pass. The telemetry rate will be 240 kbps. * Ahead has 8 passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, one at 240 kbps, and one at 160 kbps. * There are no passes for Behind during the week. Week 7 (Feb 13-19) * A 1.5 hour project interface test with Ahead using station 63 is scheduled for Tuesday, Feb 14. There will be no SSR playback or instrument commanding during this pass. The telemetry rate will be 720 kbps. * The 96th momentum dump on Ahead is scheduled for Friday, Feb 17, with ignition at 19:30 UT. This will be the 15th dump without using the gyros. * Ahead has 9 passes during the week, and overall coverage is nominal. There are seven passes at 720 kbps, and two at 240 kbps. * Recovery attempts for Behind are scheduled for Friday, Saturday, and Sunday, Feb 17-19. The first two passes are for battery recovery, and will use the 80 kW transmitter on station 26. The carrier recovery track using station 14 on Sunday will include the radio science receiver. Week 8 (Feb 20-26) * Ahead has 11 passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, and three a 160 kbps. * There are no passes for Behind during the week. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- 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) ------------------------------------------------------------------------------- Scheduled activities for Week 05: M Jan 30 (030) T Jan 31 (031) W Feb 01 (032) T Feb 02 (033) F Feb 03 (034) S Feb 04 (035) S Feb 05 (036) ------------------------------------------------------------------------------- Scheduled activities for Week 06: M Feb 06 (037) T Feb 07 (038) W Feb 08 (039) T Feb 09 (040) F Feb 10 (041) S Feb 11 (042) S Feb 12 (043) Ahead: Project interface test with station 26 ------------------------------------------------------------------------------- Scheduled activities for Week 07: M Feb 13 (044) T Feb 14 (045) Ahead: Project interface test with station 26 W Feb 15 (046) T Feb 16 (047) F Feb 17 (048) Ahead: Momentum dump, 19:30 UT Behind: Battery recovery track with station 26 S Feb 18 (049) Behind: Battery recovery track with station 26 S Feb 19 (050) Behind: Carrier recovery track with station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 08: M Feb 20 (051) T Feb 21 (052) W Feb 22 (053) T Feb 23 (054) F Feb 24 (055) S Feb 25 (056) S Feb 26 (057) ------------------------------------------------------------------------------- Upcoming events: Behind events are contingent on recovering the spacecraft. 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