STEREO Weekly Meeting Minutes for 2011-02-15 (Week 07) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 6 * On day 038 (Feb 7), during the DSS 54 support for Ahead, turbo decoder lock was lost briefly at 0843z. This resulted in the loss of four frames of instrument SSR data. See DR# N107142 for more information. * On day 041 (Feb 10), before the start of the DSS 25 support for Ahead, the antenna was declared red due to an anomaly with the antenna drive cabinet. This resulted in the loss of the entire track. To minimize science data loss, SSR pointers were repositioned and an additional two hour in duration DSS 34 handover track was added on DOY 042 (Feb 11) at 1650z. See DR# G111067 for more information. * On day 042 (Feb 11), during the DSS 54 support for Ahead, the transmitter tripped off-line at 0754z. The support continued with a downlink only. Aborted SECCHI SCMs were sent on the next track. This resulted in the loss of several minutes of instrument SSR data. See DR# M106153 for more information. * On day 044 (Feb 13), during the DSS 25 support for Ahead, and the DSS 63 support for Behind, monitor data was lost at 1526z due to a failed data server. The redundant monitor data server was placed on-line at 1547z. This resulted in the loss of 21 minutes of monitor data for both spacecraft. All SSR data were recovered. See DR# G111079 for more information. * On day 039 (Feb 8), during the DSS 54 support for Behind, instrument packets were dropped for one minute beginning at 1835z. This resulted in the loss of several minutes of instrument SSR data. A DR has been requested. This anomaly is different from previous anomalies in that packets were dropped, but the telemetry frames appeared to be correct. Packets were dropped randomly for all four instruments. * On day 039, the 16th SECCHI stepped calibration, at the aphelion/perihelion midpoint, was executed. This serves as both the midpoint roll, and the roll for 180 degree separation. * The average daily SSR playback volume was 4.8 gigabits for Ahead, and 5.2 gigabits for Behind. Week 7 * Downloading of the SECCHI SSR2 partition on Behind will be re-enabled today (Feb 15). SECCHI requests that the partition stay enabled for the foreseeable future, which is currently the case on Ahead. The percent full reading for the partition will be correct once the partition starts being read out. * Ahead has no 720 kbps passes. There are 12 passes during the week with 2.1 hours over baseline coverage. * Behind has a 720 kbps pass using D14 starting Friday Feb 18. There are 12 passes during the week, and overall coverage is nominal. * SECCHI had automatic CME event detections on both spacecraft. Behind had an event detection at 03:24 today (Feb 15) which is associated with the X2.2 flare. The time of the Ahead event detection is now believed to be at 19:54 UT yesterday (Feb 14), and may be related to the earlier M2.2 flare. * The COR1 telescope on Ahead saw a sudden jump in background on Feb 11, coincident with a debris storm. There have been four sudden changes in the COR1-A background since the start of the mission. Three of these changes have all occurred within the last four months, and are associated with debris storms. This recent cluster of contamination events is worrisome. It's unclear yet whether this represents a trend. There have been only two such events for COR1-B, neither of which was recent. Week 8 * Ahead has 720 passes on Monday (Feb 21) and Thursday (Feb 24) on D43. There are 13 passes during the week, and overall coverage is nominal. * Behind has 720 passes on Friday (Feb 25) and Sunday (Feb 27), both on D43. There are 14 tracks during the week (some very short), and there are 5.4 hours over baseline coverage. The 70 meter pass on Friday is new. Schedules continue to change because of the continuing power upgrade at Goldstone. Week 9 * A new data handling system will be uploaded to C&DH RAM on Mar 1 for Ahead, and Mar 2 for Behind. This is to add an additional APID for IMPACT to the realtime DFDs. These will be written to EEPROM two weeks later. * Ahead has 720 kbps passes on Tuesday, Mar 1 (D63), Wednesday, Mar 2 (D14 and D43), Thursday, Mar 3 (D63), and Friday, Mar 4 (D43), for a total of five 70 meter passes. There are 13 passes, and overall coverage is nominal. * Behind has 720 kbps passes on Monday, Feb 28 (D63), Tuesday, Mar 1 (D63), and Saturday, Mar 5 (D14). There are 16 passes, and overall coverage is nominal. The 70 meter pass on Saturday is new. * The station 14 pass for Ahead on day 65 (Mar 6) was taken out to assist the Messenger mission. It was replaced with a pass on station 26. Week 10 * Daily savings time in U.S. starts Sunday, Mar 13. * The 36th momentum dump on Ahead will be carried out on Tuesday, Mar 8, with ignition at 16:00 UT. * The 30th momentum dump on Behind will be carried out on Thursday, Mar 10, with ignition at 19:45 UT. * A return-to-service track on Ahead will be performed using station 15 on Friday, Mar 11, shadowing a track on station 26. Current plans are to perform the uplink and downlink on station 15, using station 26 as the shadow track. * Ahead has 720 kbps passes on Monday, Mar 7 (D43), and Friday, Mar 11 (D63). There are 12 tracks during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Monday, Mar 7 (D43), Wednesday, Mar 9 (D14), Friday, Mar 11 (D14), and Sunday, Mar 13 (D14). There are 14 passes during the week, and overall coverage is nominal. Week 11 * Ahead has 720 kbps passes on Thursday, Mar 17 (D43), Friday, Mar 18 (D43), Saturday, Mar 19 (D14), and Sunday, Mar 20 (D14). There are 11 passes during the week, and overall coverage is nominal. * Behind has 720 kbps passes on Monday, Mar 14 (D14), Friday, Mar 18 (D63), and Sunday, Mar 20 (D14). There are 12 passes during the week, and overall coverage is 2.1 hours above nominal. COORDINATED OBSERVATIONS ------------------------ ------------------------------------------------------------------------------- Scheduled activities for Week 07: M Feb 14 (045) T Feb 15 (046) W Feb 16 (047) T Feb 17 (048) F Feb 18 (049) Behind: 720 kbps downlink on station 14 S Feb 19 (050) S Feb 20 (051) ------------------------------------------------------------------------------- Scheduled activities for Week 08: M Feb 21 (052) Ahead: 720 kbps downlink on station 43 T Feb 22 (053) W Feb 23 (054) T Feb 24 (055) Ahead: 720 kbps downlink on station 43 F Feb 25 (056) Behind: 720 kbps downlink on station 43 S Feb 26 (057) S Feb 27 (058) Behind: 720 kbps downlink on station 43 ------------------------------------------------------------------------------- Scheduled activities for Week 09: M Feb 28 (059) Behind: 720 kbps downlink on station 63 T Mar 01 (060) Ahead: 720 kbps downlink on station 63 Behind: 720 kbps downlink on station 63 W Mar 02 (061) Ahead: 720 kbps downlink on station 14 and 43 T Mar 03 (062) Ahead: 720 kbps downlink on station 63 F Mar 04 (063) Ahead: 720 kbps downlink on station 43 S Mar 05 (064) Behind: 720 kbps downlink on station 14 S Mar 06 (065) ------------------------------------------------------------------------------- Scheduled activities for Week 10: M Mar 07 (066) Ahead: 720 kbsp downlink on station 43 Behind: 720 kbps downlink on station 43 T Mar 08 (067) Ahead: Momentum dump, 16:00 UT W Mar 09 (068) Behind: 720 kbps downlink on station 14 T Mar 10 (069) Behind: Momentum dump, 19:45 UT F Mar 11 (070) Ahead: Return-to-service track on station 15, shadowed by 26 Ahead: 720 kbsp downlink on station 63 Behind: 720 kbps downlink on station 14 S Mar 12 (071) S Mar 13 (072) Start of daylight savings time in US Behind: 720 kbps downlink on station 14 ------------------------------------------------------------------------------- Scheduled activities for Week 11: M Mar 14 (073) T Mar 15 (074) W Mar 16 (075) T Mar 17 (076) Ahead: 720 kbps downlink on station 43 F Mar 18 (077) Ahead: 720 kbps downlink on station 43 S Mar 19 (078) Ahead: 720 kbps downlink on station 14 S Mar 20 (079) Ahead: 720 kbps downlink on station 14 ------------------------------------------------------------------------------- Upcoming events: 2011: * Jun 27 Ahead: Switch downlink rate to 160 kbps * Jun 27 Ahead: End use of 720 kbps on 70 m DSN subnet * Jul 15 Behind: Switch downlink rate to 160 kbps * Jul 15 Behind: End use of 720 kbps on 70 m DSN subnet * Jul 25 Behind: Close approach by comet Elenin * Mar 18 Messenger - Mercury orbital insertion * Jul DAWN - Vesta arrival * Jul 13 Both: HGA calibration 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