STEREO Weekly Meeting Minutes for 2017-03-14 (Week 11) ANNOUNCEMENTS ------------- * A firewall upgrade at APL is scheduled between 15-17 UT on Apr 8. The instrument teams will have to reconnect after the upgrade. * The restricted IOnet will be upgraded on Thursday, Apr 13. See below for details. 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 10 (Mar 6-12) * On day 071 (Mar 12), during the DSS-63 support for Ahead, turbo decoder lock was lost at 1833z. This anomaly resulted in the loss of 74 frames of real-time telemetry and SSR data. * On day 066 (Mar 7), fine pointing on Ahead dropped out for 45 seconds starting at 1033z due to G&C zero wheel speed avoidance. While this is a normal occurrence within the fine pointing jitter requirements it is noted to keep the SECCHI imaging team advised. * On day 069 (Mar 10), fine pointing on Ahead dropped out for 35 seconds starting at 1033z due to G&C zero wheel speed avoidance. While this is a normal occurrence within the fine pointing jitter requirements it is noted to keep the SECCHI imaging team advised. * The average daily science data return for Ahead was 5.9 Gbits during this week. * The next Behind recovery attempts are this upcoming weekend. Week 11 (Mar 13-19) * Yesterday (Mar 13), during the station 43 pass for Ahead, Turbo decoder lock was dropped intermittently for about 5.5 minutes starting 06:46 UT due to heavy rain at the Canberra station. * The 38th SECCHI stepped calibration roll is scheduled for Thursday, Mar 16, starting at 13:50z for calibration midpoint in the orbit. The system momentum is expected to be 6 N-m-s. This is the midpoint roll, and will be the 7th roll without using the gyros. * Ahead has 10 passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, one at 240 kbps, and one at 160 kbps. * Recovery attempts for Behind are scheduled for Friday, Saturday, and Sunday, Mar 17-19. The first two passes are for battery recovery, and will use the 80 kW transmitter on station 26. There will not be any radio science recordings conducted for station 26. On Sunday, station 14 will be used with regular science recording. Week 12 (Mar 20-26) * 97th momentum dump on Ahead is scheduled for 20:30 UTC on Wednesday, Mar 22. This will be the 16th momentum dump without using the gyros * Ahead has 9 passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps and one at 240 kbps. * There are no passes for Behind during the week. Week 13 (Mar 27-Apr 2) * Ahead has 11 passes during the week, and overall coverage is nominal. There are six passes at 720 kbps, four at 240 kbps, and one at 160 kbps. * There are no passes for Behind during the week. Week 14 (Apr 3-9) * A firewall upgrade at APL is scheduled between 15-17 UT on Saturday Apr 8. The instrument teams will have to reconnect after the upgrade. The next track starts around 00:25 UT. * Ahead has 9 passes during the week, and overall coverage is nominal. There are seven passes at 720 kbps, and two passes at 240 kbps. * There are no passes for Behind during the week. Week 15 (Apr 10-16) * Passover is between Apr 10-18. Good Friday is on Apr 14, and Easter is on Apr 16. * On Thursday April 13, there will be an upgrade for the restricted IO net, T1 link. Expect to lose IO net connectivity but will re-establish this in the MOC. The outage will be from 1600-2030z. * A return-to-service demo track for station 25 on Apr 13 will need to be rescheduled because of the IOnet upgrade. * Ahead has 8 passes during the week, and overall coverage is nominal. There are seven passes at 720 kbps, and one at 160 kbps. * Recovery attempts for Behind are scheduled for Friday, Saturday, and Sunday, Apr 14-16. The battery recovery track on Friday will use the 80 kW transmitter on station 26 with no RSS recording. The other two tracks will use the 70 meter station 14, and will include the Radio Science Receiver. Week 16 (Apr 17-23) * Ahead has 9 passes during the week, and overall coverage is nominal. There are eight passes at 720 kbps, and one at 240 kbps. * There are no passes for Behind during the week. Week 17 (Apr 24-30) * The 98th momentum dump on Ahead is scheduled for Monday, Apr 24, with ignition at 16:00 UT. This will be the 17th momentum dump without gyros. * Ahead has 10 passes during the week, and overall coverage is nominal. There are nine passes at 720 kbps, and on pass at 160 kbps. * There are no passes for Behind during the week. Other * The SECCHI team is planning to do some testing with the HI-2 telescope which will require some heavier than normal telemetry. They will schedule this test during a favorable time in the DSN schedule. After the initial test they will want to carry out a longer two-week test when the DSN coverage is favorable. The MOC pointed out that one of the 70 meter stations will be going down for maintenance later in the year, so it would be best if this test could be run before then. It's thought that this station downtime starts in the middle of June, but this needs to be confirmed. COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 11: M Mar 13 (072) T Mar 14 (073) W Mar 15 (074) T Mar 16 (075) Ahead: SECCHI calibration roll, 13:50 F Mar 17 (076) Behind: Battery recovery track with station 26 S Mar 18 (077) Behind: Battery recovery track with station 26 S Mar 19 (078) Behind: Carrier recovery track with station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 12: M Mar 20 (079) T Mar 21 (080) W Mar 22 (081) Ahead: 97th momentum dump, 20:30 UT T Mar 23 (082) F Mar 24 (083) S Mar 25 (084) S Mar 26 (085) ------------------------------------------------------------------------------- Scheduled activities for Week 13: M Mar 27 (086) T Mar 28 (087) W Mar 29 (088) T Mar 30 (089) F Mar 31 (090) S Apr 01 (091) S Apr 02 (092) ------------------------------------------------------------------------------- Scheduled activities for Week 14: M Apr 03 (093) T Apr 04 (094) W Apr 05 (095) T Apr 06 (096) F Apr 07 (097) S Apr 08 (098) S Apr 09 (099) ------------------------------------------------------------------------------- Scheduled activities for Week 15: M Apr 10 (100) T Apr 11 (101) W Apr 12 (102) T Apr 13 (103) F Apr 14 (104) Behind: Battery recovery track with station 26 S Apr 15 (105) Behind: Battery recovery track with station 14 S Apr 16 (106) Behind: Carrier recovery track with station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 17: M Apr 24 (114) Ahead: Momentum dump, 16:00 UT T Apr 25 (115) W Apr 26 (116) T Apr 27 (117) F Apr 28 (118) S Apr 29 (119) S Apr 30 (120) ------------------------------------------------------------------------------- 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