SSOC Tohban Report for Week 44 (29-Oct-2001 -- 3-Nov-2001) SSOC Tohbans : K.Shibasaki,S.Uno KSC Tohbans : S.kawasoe, I.Suzuki 0. Meeting Attendees T.Kosugi, T.Watanabe, H.Hudson, M.Sawa, K.Kobayashi, Y.Ogawara, J.Khan ,K.Shibasaki, K.Matsuzaki, A.Takeda, K.Yoshimura, S.Uno ------------------------------------------------------------------------------- 1. Solar Activity The solar activity was high during the whole week. One X-class flare(Nov.4) and 14 M-class flares occurred but no X-class flares. Due to many flares, some of the SXT tables were not uploaded as was planned and KSC contacts with FL-M mode caused some delay in response. ------------------------------------------------------------------------------- 2. Standard Operations 2.1 SXT Table Uploads The following SXT tables were uploaded: JST Day UT Start Time Pass Table ID ==================================================================== Monday PM 29-OCT-01 09:05 2 011029 P2 ARS1 STD Tuesday PM 30-OCT-O1 07:21 3 011030 P1 ARS1 DIFF Wednesday PM 31-OCT-01 10:40 1 011031 P1 ARS1 DARK Wednesday PM 31-OCT-01 12:21 4 011031 P4 ARS1 STD Thursday PM 1-NOV-01 07:13 2 011101 P2 ARS1 STD Friday PM 2-NOV-01 05:30 2 011102 P2 ARS2 STD Saturday PM 3-NOV-01 04:54 2 011103 P2 ARS1 STD ==================================================================== 2.2 STT Timer Setting The STT timer was set during pass 2 on Tue 30-Oct-2001 (JST), (Pass ID : 011030-0411). ------------------------------------------------------------------------------- 3. Special Operation: 3.1 Repointing Change of Yohkoh pointing was done successfully at the pass 011031-0307. ------------------------------------------------------------------------------- 4. Errors and Problems 4.1 SXT Errors : None 4.2 DP Errors : None 4.3 BCS Errors : None 4.4 Timing generator/translator failure in the 34m tracking system at KSC The clock-signal generator/translator in the 34m dish tracking system failed on Friday, 26-Oct-01. Yohkoh data downlinks scheduled on 28-Oct-01 were changed to use the 20m antenna system. The impact to long-range 34m operation scheduling will be discussed involving ISAS ground facility experts. 4.5 FTP site of Wallops was down for two days(Oct 31,Nov 1) due to power line failure. ------------------------------------------------------------------------------- 5. NASA Station Schedule 5.1 Contact Pass Cancellations/Additions The following schedule changes occurred: ========================================================================= Week Schedule Changes ========================================================================= Real-Time 44 1 cancellations Final 45 0 cancellations Preliminary 46 0 cancellations Strawman 47 47 cancellations ========================================================================= 5.2 Contacts this week and next (see 8.12): Week Wallops Santiago Goldstone Canberra Madrid NASA Japan 44 33 1 4 0 8 46 34 45 30 0 4 3 0 37 34 5.3 Data Transmission from NASA Ground Stations ----(Copied from /home/flare1/yohkoh/dsn_corrupt/2001/01_44)---- 270 80 1054 missing data tape requested 04-Oct no response tape requested 24-Oct Closed/ same data 278 80 0852 missing data tape requested 11-OCt no response tape requested 24-Oct Closed/ correct data 281 80 1023 missing data tape requested 11-Oct no response tape requested 24-Oct Closed/ correct data 283 82 0515 not received requested 02-Nov 293 80 0120 not received requested 02-Nov 293 80 0442 not received requested 02-Nov 299 80 0240 not reveived requested 02-Nov 300 80 2310 not received requested 02-Nov 291 G16 0944 - 0953 : 15663 blocks EXPERIENCED RCVR AGC FLUCTUATIONS AND TLM DROPOUTS AT START OF DUMP PERIOD IN AUTOTRACK MODE. WENT TO PROGRAM MODE. 297 G16 0600 - 0611 : 13628 blocks After the fact DR was requested by the OPS chief to document 5,068 missing blocks on the post pass playback. TCP channel 1 had 10698 blocks and TCP cannel 2 13628 blocks. 299 C46 1730 - 1740 : No Data Unable to achieve solid lock in receivers. Attempted locking MFR's in both Auto and Manual Mode, intermittent downlink and low S/L, maximun S/L -130d Low EL pass, maximum EL at PCA was 15.9 degrees. 304 G16 0211 - 0223 : 16619 blocks STATION DID NOT GET A COMPLETE TLM DUMP ON TCP-1(HAD 11619 BLOCKS VICE 18000 BLOCKS). ERROR NOTED: TCP-1 SOCKER ERRORS. STATION TRIED CONFIGURING TCP-2 AS BACKUP BUT SPACECRAFT HAD L.O.S WITH STATION. ------------------------------------------------------------------------------ 6. KSC Pass Conflicts and Schedule : No conflict : No conflict ------------------------------------------------------------------------------ 7. Hikitsugi Items 7.1 Tohbans for Next Week SSOC Tohbans : Sawa, K.Kobayashi KSC Tohbans : Kawasoe, Yokoyama 7.2 STT Timer Setting The STT Timer Set is due on Tuesday 6-Nov-2001 (JST). 7.3 Holiday Schedule The next holiday is Sunday 11-Nov-2001 (JST). The 20m-antenna operations are scheduled for pass 2 (0:54 UT) and pass 4 (04:17 UT). These operations will be downlink only. 7.4 The OP and the command sheets for today The OP and command sheets for Monday (29 Oct JST) have already been checked and sent. 7.5 DSN downlink scheduling handover White Sands (WOTIS) took over the responsibility for the Yohkoh DSN downlink scheduling on 25-Oct-01. The setup and testing at the new ftp site were successfully conducted during the week. Wallops (WFF) is expected to stay in contact until the end of W45 (9-Nov-01). 7.6 Second-round cheking of the Y-gyro performance To check the stability of Y-gyro drift rates, another monitoring operation via ACP-SH mode is considered in W46 (starting from 5-Nov-01). The exact date will be decided next week, by consulting with solar activity/observing campaign schedules and the availability of operation supporting staffs at SSOC. ------------------------------------------------------------------------------ 8. Unchanged Hikitsugi Items from Previous Weeks: 8.01 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. 8.02 Weekend Terminators If possible, please schedule terminator opportunities on any weekend table (i.e., if room permits). 8.03 Software Problems PR_GEV with /hc keyword produces a temporary output file but doesn't print it at the printer. 8.04 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. Retries eventually worked. 8.05 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. 8.06 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) 8.07 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. 8.08 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 (Depends on azimuth. See the map on whiteboard.) Others 7.0 8.09 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 bug 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. [end of report]