20 April 1998 SOHO Daily Meeting Minutes Chairs: J. Hollis (SOC)/ A. Vourlidas (SOL) Notes: E. Zamkoff ANNOUNCEMENTS ------------- * A Building 23 planned power outage remains on schedule for this Friday, April 24 at 12:00 EST until Monday, April 27 at 12:00 EST. We will be using the re-engineering system again for telemetry data acquisition in the EOF. * On Saturday, CELIAS MTOF turned back on, no problems encountered. It is believed that a latch-up in some component in the low-voltage electronics caused the anomaly. However all power supplies and instrument components were nominal when turned on. FOT BRIEFING ------------ Spacecraft Status: NOMINAL Spacecraft Anomalies: 109/1129 CDS Watchdog Trigger(occured during gap @ 0915) 110/0358 Loss of Guide Star SSU SEU (RMW 0358 - 0601) Accomplished Activities: 107: RSL,VIRGO,CELIAS,SK MANEUVER,SWAN, SUBMODE 6 @ 1259 108: RSL,VIRGO,CELIAS, MTOF TSTOL 109: RSL,VIRGO,NON_COHO 110/0400 SSU SEU RECOVERY Planned Activities: RSL,VIRGO,SWAN,NEW GUIDE STAR,UVCS PROCEDURE TEST(1500) Upcoming Operations: Switch from Submode 6 to Submode 5 on Tuesday at 20:00 UT. Ground Anomalies: 107/1530 16 Min Late AOS D24 Block 5 RCVR Reboot. Delay in Hotbackup support 107/1601 25 Min No Commanding D24 Resweeps for Ranging 107/2002 1.5 Min TM Dropout D24 TCA 1 Failure. Nonrecoverable 108/0100 15 Min Commanding Delay D46 Resweeps for Ranging 108/0600 2 Min TM Dropout D46 Nonrecoverable Coherency Switch during ranging support. (time-tagged load not updated due to schedule change) 108/1910 20 Min Commanding Delay D16 Resweeps for Ranging 108/2042 1 Min TM Dropout d16 SFG Error Recoverable 109/1135 13 Min Commanding Delay D61 Resweeps for Ranging 109/1801 9 Min Commanding Delay D16 Resweeps for Ranging 110/1020 5 Min Commanding Delay D66 Resweeps for Ranging SOLAR STATUS ------------ Coronal holes coming into view. There were continuous transient brightenings from the young AR in the NW. Friday: AR 8194 in SW had a filament eruption at 23:46. Saturday: AR 8194 in SW had a filament eruption at 19:14, CME from AR 8203 in NW at 13:00 and 20:00, small filament eruption from AR in SE at 20:19. Sunday: AR 8194 in SW formed a dark filament at 08:00, CME at 14:15 from AR 8203 in NW, bright loops forming from AR in SE at 01:00. Monday: The dark filament in SW from Sunday erupted at 09:30 and caused a CME. M1 flare this morning, probably from filament eruption in SW. INSTRUMENT STATUS ----------------- CDS: Nominal. Weekend: had an error during the solar irradiance observing sequence (USUN_6). CDS recovered and ran spectral atlases and engineering studies. Today: observe emission above AR in SW. UVCS: Nominal. Will test a TSTOL safing procedure. Weekend: did a white light channel calibration. Today: super synoptic observation at position angle 252 for an abundances study. Fauzel Observatory in Austria is supporting UVCS observations for 10 days. LASCO: Nominal. Synoptic program. EIT: Nominal. CME watch at full resolution until 20:00 tomorrow. Seeing increase in cosmic rays due to the flare. MDI: Nominal. Doing full disk and high resolution magnetograms to support TRACE. TRACE: Door opened this morning. First images should be here soon. Timeline for today shows dark frames before door opening, focus and fine tuning of image stabalization system. (See http://chippewa.nascom.nasa.gov/TRACE/ops/timeline) Tonight: movies of AR in the NW and the prominence on NW limb. GOLF: Nominal.