SSOC Tohban Report for Week 35_95 (August 28 - September 3, 1995) SSOC: K. Yaji, K. Shibasaki KSC : K. Hori, M. Nishio Attendances of the Weekly Operation Meeting on September 04 (Mon.): T. Sakao, M. Weber, R. Kano, J. Kahn, M. Sawa, Te. Watanabe, G. Slater, Ta. Watanabe, N. Nitta, K. Yaji, K. Shibasaki, H. Hudson, M. Shimojo 1. Solar Activity ----------------------------------------------------- Solar activity was low whole week. There were no C-class events. The largest event was B6.4 on Aug. 30. Most of the activities were located at north west part of NOAA 7903. 2. Standard Operations ------------------------------------------------ 2.1 SXT Table Uploads : 7 tables --------------------------------------------------------------------- KSC Time (start:JST=UT+9) Pass# Table ID --------------------------------------------------------------------- 28-Aug-95 (16:22) 3 950828 P3 ARS1 DARKCAL 29-Aug-95 (13:14) 2 950829 P2 ARS1 STD+LONG 30-Aug-95 (13:34) 2 950830 P2 ARS1 OFF-PNTS 30-Aug-95 (17:00) 4 950830b P4 ARS1 STD+LONG 01-Sep-95 (14:12) 3 950901 P3 ARS1 SPARTAN-A 02-Sep-95 (09:25) 1 950902 P1 ARS0 SPARTAN-B 02-Sep-95 (14:32) 4 950902B P4 ARS1 SPARTAN-A --------------------------------------------------------------------- Every time a block command "BC 8C 05" was also executed. This is for dumping SXT patrol images. 2.2 STT Timer Setting The STT Timer was set on Aug. 29 (in the pass 950829-0309). 3. Errors & Problems ------------------------------------------------- 3.1 Telemetry problem In the first pass on Aug. 28 (950828-0308), OP WRITE was hampered by the telemetry trouble. The trouble was recovered soon, however, OP START was delayed 37 seconds. This situation was cleared in the next KSC contact (3rd pass, 950828-0515) by OP_STOP/OP_CONTINUE commands. The real cause of the telemetry trouble is not known yet. The telemetry antenna (20 m) failed to follow the satellite. The recovery was done by switching from the "tracking mode" to the "program mode". Similar phenomena were detected by ASCA (1st pass on Aug. 26, 1st pass on Aug. 29) and also by SFU. No error alarms were detected in the KSC telemetry system (the antenna and the receivers). All these phenomena occurred at the azimuth angle of 90 - 100 degree, at the same JST 13h, and at low elevation angle. Only the S-band tracking mode is suffering from the trouble. The X-band tracking mode is OK. Very strong S-band noise on the ground might get in through the sidelobe of the 20 m antenna. 3.2 Error of op_first_guess An error was found in the op_first_guess in the week 34. (OP STOP appeared in the midst of the OP, not at the end.) The bug in op_first_guess program was located and fixed by Lemen san. However, a new error seems to have crept into the op_first_guess. Normal OPs have two KSC contacts at the end. In these contacts, KSC LOS should be with QT-ME. However, the earlier one was found to be with QT-H in "950831-0103 OP". Due to this QT-H mode, an extra campaign observation was inserted after the contact and QUIET RATE HIGH was not inserted before the last KSC contact. The occurence probability of this phenomena seems rather high. 3.3 SXT Al.1 image Another big straylight_hole was found around the north pole. This may be due to the probable entrance filter damage on Aug. 16. 3.4 DSN Data 1) The data from Wallops on Aug. 26 (00:29-00:40) and 28 (22:39-22:49) were shorter than expected. 2) The data from Goldstone on Aug. 28 (02:41-02:49) were broken. Retransmitted data were also broken. We are requesting retransmission of these three data sets. 3.5 SXT Bit-map error SXT Bit-map error was detected on Sep. 2 Pass 1, and was recovered in the same pass. 4. DSN Communications ------------------------------------------------------ 4.1 DSN Strawman Schedule for W38 We cancelled 18 DSN contacts from the Strawman Schedule for W38. 4.2 DSN Preliminary Schedule for W37 None 4.3 DSN Final Schedule for W36 None. 4.4 DSN Final Schedule for W35 None. 4.5 Pass additions None. 5. YOHKOH/ASCA/SFU Pass Conflicts at KSC ---------------------------------- For W35, 5 KSC passes were lost because of the conflicts with ASCA. The current pattern is that for a couple of days the orbits are almost exactly out of phase, but in the following couple of days the orbits are nearly perfectly in conflict, we will lose half of the KSC contacts in these cases. There are no current pass conflicts between Yohkoh/ASCA and SFU. 6. Special operation Offset Pointing and SPARTAN A new set of OGs for offset pointing was issued and uploaded on Aug. 30 (950830-0206). This set of OGs is for Offset Pointing observations to study the current SXT situation after the probable damage of the entrance filter(s) and also to do coordinated observation with SPARTAN. No offpoint terminator images were taken. The launch of SPARTAN has been postponed by a week. New launch date is Sep. 7 (Wed.). 7. Holiday Schedule The next holiday will be Sunday, September 10. ************************************************************************** 9. Hikitsugi Items -------------------------------------------------- 9.1 Tohbans for Week 36 KSC : M. Nishio and S. Nagata SSOC : Ta. Watanabe and K. Fujisaki 9.2 STT timer setting The next STT timer set is due on Tuesday, 5 Sep. (JST). 9.3 OP_FIRST_GUESS ( from last week's report ) A couple of misses of DP rate switches in SAA have been reported in the output of 'op_first_guess'. In the week 34 and 35 no problem is found about the DP rate switches, but the tohbans should take care about this item. A new bug might have crept into 'op_first_guess' program after the fix of the bug found in the previous weekend OP generation. Please check OPs carefully (ref. 3.2). 9.4 SXT patrol image dumps ( from last week's report ) The block command "BC 8C 05(HEX)" should be executed with each table change. This is to dump an SXT patrol image for reference. 9.5 Offpoint terminator images The terminator-offpointing program was given a pause in the week_34. However, the general rule is as follows; when SSOC tohbans make a draft OP with SXT CMPN OBS's by 'op_first_guess', they should send the draft OP to the SXT_CO in D-toh via fax and consult him whether the offpoint OG's are to be inserted or not. If there are SXT_CO's requests, he send back a fax of requests, and SSOC tohbans will be required to manually insert the offpoint OGs into the OP tables. 9.6 E-mail Yohkoh Operation Report from KSC Since 10 Aug 1995, KSC YOHKOH tohbans have sent via e-mail to flare1, SSOC, besides faxes. SSOC tohbans save this report into the directory 'yohkoh/ops_rep/' with the filename as, for example, '950904.rep'. ---------------------------------------------- END of REPORT