SSOC TOHBAN REPORT FOR WEEK 19 (May 9 - May 16, 1994) Ryouhei KANO and Masaki SAWA 1 SOLAR ACTIVITY The solar activity is very low. However, the base line of GOES slowly increase about from A5 to B0. Some small flares occurred since May 11. The annular eclipse occurred on May 10. 2 STANDARD OPERATIONS 2.1 OG Write Date(UT) Pass Purpose -------- ---- ------- May 9 940509-0927 Eclipse Observation May 13 940513-0723 HXT Fine Gain Adjust + BCS test (This OG upload failed and succeed in the next pass.) 2.2 SXT table uploads Date(UT) Pass ID -------- ---- -- May 9 940509-0927 940509 P1 ECLIP-1 TST 940509-1031 940509 P2 ECLIP-2 TST 940509-1134 940509 P3 ECLIP-5 TST May 10 940510-0928 940510 P1 ECLIPSE-1 (CANCELED due to ERR) 940510-1031 940510 P2 ECLIPSE-2 940510-1135 940510 P3 ECLIPSE-5 (CANCELED due to ERR) May 11 940511-0825 940511 P2 ARS1 DKCAL May 12 940512-0929 940512 P2 ARS1 STD+LONG 2.3 HXT calibrations & Fine Gain Adjustment HXT gains were adjusted in Pass2 of May 13, before and after which HXT calibration was done three times for each (Pass2,3,4 of May 12, Pass3,4 of May 13 and Pass2 of May 14). 2.4 STT Timer was set on May 9, Pass2. Next STT Timer should be set by May 17. 3 SPECIAL OPERATIONS 3.1 Test of Eclipse Observation The complete rehearsal of the eclipse of May 10 was carried out on May 9. Three tables were uploaded: Two for special and the last for standard. Several special OGs for SXT, BCS and the attitude were added into OP at the proper timings for each. Although the rehearsal finished in success without BCS data gap, the real operation for the eclipse was changed. 3.2 The Eclipse Observation The eclipse observation ended in failure. Only 4 poor FFIs catched the eclipse. This is because the eclipse commitee does not work properly. Thus, many problems occurred. One of them is the occurrence of two SXT errors, which Section 4.1 reports later. Another is the overwriting of BDR. This was caused by SSOC's mistake when Bentley san requested to avoid the overwriting for BCS without the campaign mode a few hours before Pass1. 3.3 Test of the Standard BCS Setup Bentley san will change the standard BCS setup included in LOS-OG. The test for this change was requested after Pass1 and Pass2, but due to the failure of OP-OG write in Pass1, the test only after Pass2 was done. 4 ERRORS AND PROBLEMS 4.1 SXT errors A BIT MAP ERROR was found in pass1 on May 9 (PASS 940509-0927) and cleared during the pass by Yobi-C. A STATUS READ ERROR was found in pass1 on May 10 (PASS 940510-0928). Yobi-A & B were executed in order to move SXT into the safe mode. In the next pass, SXT was recovered by Recovery Plan-1a. This error might be caused by SEU (Single Event Upset). A NIGHT COMMAND ERROR occurred at 15:38UT on May 10, just before the eclipse observation. SXT moved to the safe mode by Yobi-A and was recovered by Yobi-C in Pass1 of the next day. Because removing the campaign mode, we have no data at the moment the error occurred. Thus, SXT group has not concluded the reason yet. 4.2 a Broken FFI taken on 26-Feb-94 A FFI image taken on Feb.26,1994 is broken in the SIRIUS data base. In a half of that, a strip of image appears repeatly. Kano will ask Kato san this cause. 4.3 OP-OG Write error OP-OG write in Pass1 of May 13, 940513-0723, failed. Because KSC tohbans and NEC commander were not familiar to this error and do not know KOSUGI-manual, they remained OP-STOP, ACS-HI and ANT-A. By retry command of OP-OG write, Yohkoh returned to proper situation. 5 DSN Communications 5.1 DSS-16 DOY117/1454-1505, all of whose data was lost. "The MPA failed two minutes prior to BOT on this pass and DSS 16 was unable to support. Several YOHKOH and ASCA passes were subsequently supported with DSS 17 while the hard disk on DSS 16's MPA was replaced. (Wendell Keller)" 5.2 DSS 66 DOY132/0312-0322, which NASA canceled emergently and whose data was lost. "The DSS 66 pass DOY 132/0312-0322 has been cancelled to allow DSS 66 to support a DSPSE maneuver. (Wendell Keller)" 6 YOHKOH/ASCA Pass Conflicts Hara san set the program which prints out two figure and one warning text automatically on every Wednesday. 7 HIKITSUGI 7.1 Tohbans for W20 (May 16-May 23): SSOC: Marubashi,K., Hori,K. KSC: Koshiishi,H., Fukushima,H. 7.2 STT Timer should be set on May 17. 7.3 QT RATE ME/HI should kept being manually inserted in SAA. 7.4 You have to consult with Nagase san(schedule manager of ASCA team) when you decide the next week schedule. He is at room 1611, ext.2611. 7.5 Remember to delete and condense old files on the Mainframe once each week. 7.6 The meeting of ASJ is held from May 17 to 19 in Osaka. Japanese SXT super tobans also attend it. END OF REPORT