SSOC Tohban Report for Week 24 (11-Jun-2001 to 17-Jun-2001) SSOC Tohbans : R. Kano, M. Miyashita KSC Tohbans : Y. Saito, A. Asai 0. Meeting Attendees H. Hudson, R. Kano, J. I. Khan, T. Kosugi, D. E. McKenzie, M. Miyashita, Y. Ogawara, A. Takeda, Te. Watanabe, K. Yoshimura ------------------------------------------------------------------------------- 1. Solar Activity Solar Activity was a little bit high. There were 3 GOES M-class flares and many C-class flares this week. The GOES background level was almost the C level. ------------------------------------------------------------------------------- 2. Standard Operations 2.1 SXT Table Uploads The following SXT tables were uploaded: JST Day UT Start Time Pass Table ID ================================================================= Monday AM 11-JUN-01 02:42 2 010611 P2 ARS1 DRK Monday PM 11-JUN-01 06:05 4 010611 P4 ARS1 STD Tuesday AM 12-JUN-01 01:01 1 010612 P1 ARS1 DIF Tuesday PM 12-JUN-01 06:05 4 010612 P4 ARS1 STD Wednesday AM 13-JUN-01 02:41 2 010613 P2 ARS1 STD Thursday AM 14-JUN-01 02:41 2 010614 P2 ARS1 STD Friday AM 15-Jun-01 01:00 2 010615 P2 ARS1 STD Saturday AM 16-Jun-01 00:59 2 010616 P2 ARS1 STD ================================================================= 2.2 STT Timer Setting The STT timer set was done during pass 1 (Pass ID : 010605-0413) on Thursday 14-Jun-01. ------------------------------------------------------------------------------- 3. Special Operations 3.1 Restart Operation of Canopus Tracking During this eclipse period of Canopus, Yohkoh made clockwise rotation around Z-axis. We rotated Yohkoh counter-clockwise by 13.5 degree in total since June 13 (pass 010613-0413). Then, at pass1 on June 15, we found that STT cought Canopus. During this operation, we failed to get STT MAPs. Watanabe-san and Masuda-san found that the AOSLOSGD program does not predict the Canopus window exactly. Therefore, STT MAP operations based on AOSLOSGD was not carried out at the proper timing. The SOP program, which is usually used for the calcuration of the command for STT Timer Set, should be used. This morning (22:31-22:36UT on June 17), we succeeded the STT MAP operation based on the SOP prediction. Because STT MAP is used only for the restart operation of Canopus tracking, we will stop the daily STT MAP operation. 3.2 34m CMD operation test From June 14 to 16, the 34m CMD operation test was carried out by using Yohkoh, GEOTAIL and HALCA. The Yohkoh operation for pass1, pass2 & pass3 on 15 June (010614-3447, 010615-3402 and 010615-3406) was done with the KSC 34m antenna. We cannot find any trouble about the command upload and the data download with 34m antenna. However, after the medium/low-bit-rate downlink test at pass3, we had no time to execute "BDR REC", and lost the data between pass3 and pass4 (15-June 02:54:46 - 04:22:42 UT). 3.3 CMG: A-gyro OFF (See also 3.1 in the 2001-w23 report) Since June 7 (pass 010607-0309), the ACS control mode has been fixed to "FAQ (fine acquisition)" instead of "NOR (normal)", because of the trouble by one of Control Momentum Gyros (CMG-A). After the eclipse period of Canopus, we turned off CMG-A at pass4 on June 15 (010615-0309), and returned "NOR" at pass2 on June 18 (010618-1547) successfully. ------------------------------------------------------------------------------- 4. Errors and Problems 4.1 SXT Errors: None. 4.2 DP Errors: None. 4.3 BCS Errors: None. 4.4 FAX troubles For the last few weeks, the FAX machine in B-toh had a trouble about the connection from any KSC FAX machines to SSOC B-toh machine. This week, an engineer and Yoshimura-san checked it and tried to fix the trouble. The reason of the trouble is not so clear, but it looks working well. ------------------------------------------------------------------------------- 5. NASA Station Schedule 5.1 Contact Pass Cancellations/Additions The following schedule changes occurred: =============================================================== Week Schedule Changes =============================================================== Real-Time 24 4 cancellations Final 25 0 cancellations Preliminary 26 0 cancellations & 10 additions requested Strawman 27 57 cancellations =============================================================== 5.2 Contacts this week and next (see 8.12): Week Wallops Santiago Goldstone Canberra Madrid NASA Japan 24 26 0 3 5 4 38 32 25 29 0 1 8 1 39 32 5.3 Data Transmission from NASA Ground Stations ----(Copied from /home/flare1/yohkoh/dsn_corrupt/2001/01_24)---- 141 16 0835 corrupted requested 28-May Closed/ correct data 140 16 1135 not received requested 22-May no response requested 24-May Closed/ same data 143 16 0813 corrupted requested 04-Jun Closed/ same data DOY-151 G16 0450 - 0501 : 14237 blocks Late TLM lock on SOLA data. Antenna oscillating in "AUTO MODE". TLM in solid lock @ 045600z. Problem corrected when antenna was placed in "PGM MODE" and bias best of 0 was entered. DOY-153 G16 0308 - 0320 : 6455 blocks Acquired spacecraft out of keyhole. Had probolems acquiring the main beam. DOY-154 G16 0308 - 0320 : 17816 blocks Had problems acquiring the downlink main lobecoming out of keyhole and the autotrack system was not maintaining a solid track. Reverted to Program track mode. ------------------------------------------------------------------------------ 6. KSC Pass Conflicts and Schedule No conflicts No conflicts ------------------------------------------------------------------------------ 7. Hikitsugi Items 7.1 Tohbans for Next Week SSOC Tohbans: Te. Watanabe/T. Sakao KSC Tohabns: A. Asai, Eto 7.2 STT Timer Setting The STT Timer Setting will be due on Tuesday 19-Jun-2001 (JST). 7.3 Holiday Schedule (KSC 34m antenna Tel: 0994-67-3152) The next holiday is 24-June-2001 (JST). The 34m-antenna operation is scheduled for Pass 1 (04:53:44JST) and Pass 4 (09:58:00JST). 7.4 Eclipse Operation On June 21, there are three eclipse. 12:24:54.2 - 12:44:41.7 UT 12:47:55.5 - 13:08:02.9 UT 14:13:30.6 - 14:31:26.3 UT (predicted by Soma-san) I (R.Kano) ask next SSOC tohbans to insert at least two commands in Thursday's OP for the attitude control. June 21, 12:20 UT OG-114 ORBIT TIMER DIS June 21, 15:10 UT OG-115 ORBIT TIMER ENA1 I also ask SXT_CO to arrange the other commands (CMPN OBS ON/OFF, the bit rate change etc.) based on an observation plan if it exist. 7.5 STT MAP operation in OP (see 8.10) We will stop the daily STT MAP operation in OP. ------------------------------------------------------------------------------ 8. Unchanged Hikitsugi Items from Previous Weeks: 8.1 DSN Pass Additions (2000-w20; modified 2001-w10) >>>>>*** DON'T FORGET TO REQUEST PASS ADDITIONS!!! ***<<<<<<< Yohkoh loses DSN passes as follows: (1) Canceled by the SSOC tohbans (2) 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 (2) could be replaced by ones from case (1). -------------- Thus it may be possible to request pass additions for the PRELIMINARY and FINAL week schedules from the [case (1)] STRAWMAN cancellations. Only request additions from the crossed out cancellations done by SSOC. The routine to use is ADD_DSN: e.g., IDL> add_dsn, 28, /prelim 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. 8.2 Weekend Terminators If possible, please schedule terminator opportunities on any weekend table (i.e., if room permits). 8.3 Software Problems PR_GEV with /hc keyword produces a temporary output file but does not print it at the printer. 8.4 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. (3)(2001-w06) OP_FIRST_GUESS frequently got confused about start times, trying to read weekly files extending forward years from the present. Re-tries eventually worked. 8.5 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. 8.6 34m ANT Operation (2000-w33, 20001-w12) 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 accommodate many 34m passes without sacrificing even more DSN passes. 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). Try to avoid zenith passes ( Max. El. >76 degree) in planning. However, do not try to change the already fixed schedule just because the pass chosen turns out to be a zenith pass. There's no problem using the zenith pass with extra few op commands. (2001-w12) 8.7 Weekend DSN 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). HALCA groups operate the satellite from ISAS. SSOC tohbans must be careful to transfer OP and SXT tables in the following periods, an hour before the beginning 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 STT MAP operation in OP (2000-w42, revised at 2000-w53, 2001-w08, 2001-w24) Since 2001-w25, we will stop the daily STT MAP operation in OP. 8.11 Bug-fix Report about the Attitude Determination Software (ADS) at 200-w53 Related with the Y2K problem, a software bug was found in the attitude detection software. The problem occurred 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 Sirius 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. 8.12 print_contact (2001-w07) It's helpful to see the actual statistics of the DSN/Wallops station passes. The program "PRINT_CONTACTS" does this for inclusion in the weekly report, e.g. IDL> print_contacts,[6,7] lists the passes for weeks 6 and 7. 8.13 New 26m Equipment for Yohkoh (2001-w23) We received email from Ida Millner @ GDSCC @ NASA to advise us about the transition to new 26m equipment for Yohkoh which will start sometime after DOY 215. Yamada-sensei at ISAS will handle the consultation related to these changes. Future SSOC tohbans should keep an eye on the station identifiers in the schedules we receive from DOY 215 to check for possible software modifications which may be necessary if these change. > From: Millner, Ida > Subject: OPD-SOLA-001: Transition to 26M New Equipment for Solar-A (SOLA) > > 1) PURPOSE: > To advise the supporting stations of the transition to the 26M new > equipment for Solar-A. > > 2) EFFECTIVE PERIOD: > Upon receipt through DOY 215, when another OPD will be issued or a PCN > supercedes this OPD. [end of report]