SSOC Tohban Report for Week 01 (4-Jan-2001 to 7-Jan-2001) SSOC: T.Shimizu KSC: K.Ichimoto 0. Meeting Attendees No meeting was held because of a national holiday. ------------------------------------------------------------------------------- 1. Solar Activity Yohkoh operation was resumed at KSC from 4 Jan after the new year(century) holidays. The GOES X-ray background level stayed around B8 with several C class flares. An active region coming from the north east limb was the brightest. C4.5 flare at the peak around 9 UT on 4 Jan was well observed with Yohkoh from the pre-flare phase through after the peak. ------------------------------------------------------------------------------- 2. Standard Operations 2.1 SXT Table Uploads The following SXT tables were uploaded: JST Day UT Start Time Pass Table ID ====================================================================== Thursday PM 04-JAN-01 10:39 4(note) 010104 P3 ARS1 STD Friday PM 05-JAN-01 10:43 4 010105 P4 ARS1 DARK Saturday PM 06-JAN-01 05:40 1 010106 P1 ARS1 DIFF Saturday PM 06-JAN-01 10:46 4 010106 P4 ARS1 STD ====================================================================== Note: The upload was shifted because of FLARE mode on the scheduled pass 2.2 STT Timer Setting The STT timer set was done at pass 2 on Friday (PASS ID: 010105-0515) ------------------------------------------------------------------------------- 3. Special Operations None ------------------------------------------------------------------------------- 4. Errors and Problems 4.1 SXT Errors SXT was returned with SEU hang-up (status read error and shutter/filter errors) from the new year holiday. At pass 1 on 4 Jan (PASS ID: 010104-0412), Yobi-B was issued to make SXT safe. Recovery plan was performed at pass 2 on the same day (PASS ID: 010104-0515) and SXT started its observation. 4.2 DP Errors None 4.3 BCS Errors Check sum error was found at Pass 1 on 6 Jan (PASS ID: 010106-0412) and BCS was reset with BCS recovery procedure at pass 2 (PASS ID: 010106-0515). 4.4 KSC workstation is down A workstation (flare4) cannnot be rebooted after the new year holiday. So KSC cannot check SXT images in real time. WS manager will ship an alternate workstation to KSC soon. 4.5 Partial data loss at KSC 34m operation Playback data was partially lost at a KSC 34m pass on 7 Jan, Sunday (PATH ID: 010107-0412). Strong wind (maximum wind speed over 25m/s) at KSC caused an antenna lock off for a few minutes during the Yohkoh tracking. ------------------------------------------------------------------------------- 5. NASA Station Schedule 5.1 Contact Pass Cancellations/Additions The following schedule changes occurred and/or requested: ======================================================================= DSN/NASA Week Schedule Changes ======================================================================= Real-Time 01 1 cancellations Final 02 2 cancellations Preliminary 03 0 cancellations 1 addition request Strawman 04 42 cancellations ======================================================================= 5.2 Data Transmission from NASA Ground Stations ----(Copied from /home/flare1/yohkoh/dsn_corrupt/2001/01_01)---- 349 82 0812 corrupted tape requested 21-Dec no response tape requested 26-Dec no response tape requested 05-Jan 361 82 0537 corrupted tape requested 05-Jan 364 82 0043 corrupted tape requested 05-Jan DOY-001 M66 2008-2019 : 12605 blocks T5C1 and T5C2 failed at TLM I/L time(201056z). T5C1 and T5C2 were started when clock was present. T5C1 came I/L but no data being output T5C2 didn't achieve lock. Both CHN's were restarted. Blocks delivered : T5C1 12605 T5C2 11137. ------------------------------------------------------------------------------- 6. KSC Pass Conflicts and Schedule - Yohkoh lost 1 pass for HALCA. - Yohkoh will lose 3 passes for HALCA. ------------------------------------------------------------------------------- 7. Hikitsugi Items 7.1 Tohbans for Next Week SSOC: Nakakubo, Ito KSC: Ichimoto(-12), Matsuzaki(11-) 7.2 STT Timer Setting The STT Timer Setting is due on Tuesday, 09-JAN-01 JST. 7.3 Holiday Schedule (KSC 34m antenna TEL: 0994-67-3152) 14-JAN-01 02:41 - 02:56 UT 7.4 Special Operation None ------------------------------------------------------------------------------ 8. Unchanged Hikitsugi Items from Previous Weeks: 8.1 Weekend Terminators If possible, please schedule terminator opportunities on any weekend table (i.e., if room permits). 8.2 Software Problems PR_GEV with /hc keyword produces a temporary output file but does not print it at the printer. 8.3 OP_FIRST_GUESS Problem (1)(1999-w38, 1999-w45) In a situation with two KSC cancellations on each of two days (a rare condition) the BDR optimization feature of OP_FIRST_GUESS crashed. After experimentation, we found that it ran OK without the final cancellation request (two the first day, but just the first one on the second day). The second one then had to be removed manually. Records of the problem were forwarded to Lemen-san, but no answer had arrived at the time of writing. (2)(1999-w46, 1999-w45) During the preparation of 991109-1238 OP, 991110-1135 OP and 991111-1032 OP OP_FIRST_GUESS crashed with the message "OP_START_END: problem with detection of LOS/AOS/DSN Repro events". This problem was solved by changing OP_FIRST_GUESS options: choose optimization 1 rather than 2. 8.4 Keeping Wallops Contacts (1999-w42, 1999-w45) This is not a new policy, but to emphasize (paraphrased from e-mail from Hugh Hudson): We should keep all valid Wallops passes, independent of day/night status, in order to maximize our Wallops use and minimize our DSN use. NASA won't give us many DSN passes anyway, so if we select a Goldstone pass in preference to a Wallops one, we'll normally just lose both. Another reason is that CANCEL_DSN software needs some repair, since it seems to replace the DSS identifier WGS with 0. This is likely to cause confusion, but of course if we don't cancel Wallops passes we won't have this problem often. 8.5 DSN Pass Additions (2000-w20) *** Don't forget to request pass additions! *** Yohkoh loses DSN passes as follows: (1) Canceled due to conflicts with ASCA (by Seko-san) (2) Canceled because Santiago is unavailable (Actually it is now available until end of 2000) (3) Canceled by the SSOC tohbans (4) Deleted by DSN The Tohbans SHOULD COMPARE the STRAWMAN, PRELIMINARY and FINAL schedules -------------- for each week to see if some of the passes lost by case (4) could be replaced by ones from case (3). This means it may be possible to request pass additions for the PRELIMINARY and FINAL week schedules from the (case (3)) STRAWMAN cancellations. (The cancellations by Seko will generally be marked in red ink, and those by SSOC by pencil: Only request additions from the penciled cancellations). The routine to use is ADD_DSN: e.g., IDL> ADD_DSN, 28, /prelim and IDL> ADD_DSN, 29, /final Decide on the complete list of passes to be added and select them like CANCEL_DSN. Then ftp and email the appropriate file. 8.6 34m ANT Operation (2000-w33) 34m Operation will be done only on Sunday (=Yohkoh holiday) for up to 2 or 3 passes. There will be no 34m OP to compensate for the lost pass due to the conflict with the other satellites. For further details, please ask Kosugi-san. Note that 34m operation requires more CE slots in OP table than DSN operation does. Weekend OP cannot accomodate many 34m passes without sacrificing even more DSN passes. Due to the narrow antenna beam, acquision of the signal from the satellite at the first contact need some time. It is suggested that the KSC REPRO should start one minutes later compared to the 20 m operation. (w46) Also, max elevation of the 34 m antenna should be checked carefully using Weekly Visible Diagram (do not trust op_first_guess nor AOSLOS listing). Max elevation should be less than 76 degree. (w46) 8.7 Weekend DNS passes (2000-w49) We used to schedule 12 DSN passes during the weekend, but now we have two passes with the KSC 34m antenna. So only 9 or 10 DSN passes should be scheduled for the weekend. Please be sure to cancel extra passes as early as possible. 8.8 DSN Max Elevation DSN max elevation must be higher than the following value: Contact Max El.(degrees) Madrid 10.0 (2000-w45) Santiago 13.5 (2000-w44) Wallops 6.5 Others 7.0 8.9 OP and SXT Table Transfers Trouble (2000-w34) OP and SXT tables can not be transferred to KSC correctly when the MS computer at ISAS is in Initial Program Load(IPL). ASCA and HALCA groups operate the satellite from ISAS. We must not transfer OP and SXT tables in the following periods: "An hour before the beginning of HALCA/ASCA contact and an hour after the end of HALCA contact." As for IPL of MS computer at KSC, operators confirm if new OP and SXT tables come to MS computer at ISAS after the IPL. 8.10 Pass Conflict Issues In the operation meeting among ASCA, AKEBONO, HALCA, and YOHKOH, held on Thursday 31-Aug-00, ASCA group proposed that (1)they used only one pass a day, time of which is located between 4 and 20 (JST), and that (2)they wouldn't use DSN contacts for ASCA operations. 8.11 STT MAP operation in OP (2000-w42, revised at 2000-w53) If possible, please schedule the STT MAP operation just before the 1st KSC Pass on next day. The OP commands to be insrted in OP are as follows; OG-030(DEC) CMPN OBS ON OG-117(DEC) STT MAP START ; 1 step after CMPN OBS ON OG-118(DEC) STT MAP END ; 5 min (10steps) after STT MAP START OG-031(DEC) CMPN OBS OFF ; 1 step after STT MAP END Plese insert these command manually in OP schedule. The timing of these commands must be assigned around the mid-time of Canopus tracking window (note that the Canopus tracking does not work normally in this window). It is prefer that the command work during the night period of the satellite. 8.12 Bug-fix Report about the Attitude Disition Software (ADS) at 200-w53 Related with the Y2K problem, a software bug was found in the attitude detection software. The problem occured in the procedure to search the orbital element file. In the program including the bug, the attitude of the Yohkoh satellite was calculated using the latest orbital elements in DASD or Serius database, while it must be done using the elements of the day nearest to the observation date. This buf has been fixed now. This bug causes the large attitude error when the observation date and the calculation date of the attitude are largely different. From 2000 Jan. to 2000 Sep., there are 10 candidates with the attitude error greater than one minutes of arc, which are as follows (obs. date); 27-Apr-2000, 28-Apr-2000, 13-Sep-2000, 14-Sep-2000, 7-Jan-2000, 11-Sep-2000, 9-Mar-2000, 8-Jan-2000, 28-Sep-2000, 12-Sep-2000. Re-calculation of the attitude is scheduled to these 10 cases. [end of report]