SSOC Tohban Report for Week 50 (10-Dec-2001 -- 16-DEC-2001) SSOC Tohbans : T. Morimoto I. Suzuki KSC Tohbans : K. Shinoda T. kichiraku 0. Meeting Attendees Ogawara, Kosugi, Watanabe, Khan, Sakao, Hara, Kano, Sato, Takeda Yosimura, Morimoto ------------------------------------------------------------------------------ 1. Solar Activity The solar activity was moderately high. There were 9 M-class flares and 2 X-class flares during last week. Especially, activity in NOAA 9733 was high and both of X-class flares occured in the region. ------------------------------------------------------------------------------- 2. Standard Operations 2.1 SXT Table Uploads The following SXT tables were uploaded: JST Day UT Start Time Pass Table ID ==================================================================== Monday PM 10-DEC-01 10:33 2 011210 P2 ARS1 STD Tuesday PM 11-DEC-01 12:08 4 011211 P4 ARS1 DARK Wednesday PM 12-DEC-01 07:00 1 011212 P1 ARS1 DIFF Thursday AM 12-DEC-01 10:21 3 011212 P3 ARS1 STD Thursday PM 13-DEC-01 08:34 2 011213 P2 ARS1 STD Friday PM 14-DEC-01 08:28 2 011214 P2 ARS1 ECLIPSE ==================================================================== 2.2 STT Timer Setting The STT timer was set at pass 2 on Tue 11-Dec-2001 (JST). ------------------------------------------------------------------------------- 3. Special Operation: 3.1 Annular eclipse The venus eclipse was occurred. The following operations have been done. December 14 Pass-1: OP+OG Write for the eclipse Pass-2: SXT Table Write for ECLIPSE Pass-3: OP Rewrite for the eclipse ------------------------------------------------------------------------------- 4. Errors and Problems 4.1 Before December 14 4.1.1 SXT Errors : None 4.1.2 DP Errors : None 4.1.3 BCS Errors : None 4.1.4 Software problem KSC tohbans reported that the date for obtained data at KSC showed a time lag of one day, though the date for reformated data had no problem. 4.2 December 14 During the eclipse, Yohkoh lost the sun presence signal, and ACP safe hold was triggered. Yohkoh's attitude was highly disturbed, and Yohkoh started to rotate nearly around its Y-axis. During the subsequent night for Yohkoh, UVC (Under Voltage Control) was also triggered. The Yohkoh recovery operations started at the second pass of Saturaday. ------------------------------------------------------------------------------- 5. NASA Station Schedule 5.1 Contact Pass Cancellations/Additions The following schedule changes occurred: ========================================================================= Week Schedule Changes ======================================================================== Real-Time 50 9 cancellations 1 additions requested Final 51 all contacts were canceled Preliminary 52 all contacts were canceled Strawman 01 48 cancellations ========================================================================= 5.2 Contacts this week and next (see 8.12): Week Wallops Santiago Goldstone Canberra Madrid NASA Japan 50 30 4 0 2 2 38 27 51 0 0 0 0 0 0 31 5.3 Data Transmission from NASA Ground Stations ----(Copied from /home/flare1/yohkoh/dsn_corrupt/2001/01_50)---- 337 80 0142 missing data tape requested 14-Dec 338 74 1334 missing data tape requested 14-Dec 339 74 1843 missing data tape requested 14-Dec 342 82 0435 corrupted tape requested 14-Dec 339 66 2218 not received requested 14-Dec ------------------------------------------------------------------------------ 6. KSC Pass Conflicts and Schedule : 5 conflicts (4 for HALCA and 1 for AKEBONO) : 1 conflicts (1 for HALCA and 0 for AKEBONO) ------------------------------------------------------------------------------ 7. Hikitsugi Items 7.1 Tohbans for Next Week SSOC Tohbans : Kano & Sano_I KSC Tohbans : Kichiraku & Katsukawa 7.2 STT Timer Setting Yohkoh recovery operation will be done instead. 7.3 Holiday Schedule The next holiday is Sunday 23-Dec-2001 (UT). 7.4 The OP and the command sheets for today No OP and command sheets are prepared for today, yet. All schedules are to be decided before the contacts. 7.5 DSN downlink scheduling Handover White Sands (WOTIS) took over the responsibility for the Yohkoh DSN downlink scheduling. From W46, all DSN contacts should be made through WOTIS. 7.7 SXT tohban contact The SXT_COs have moved from D-toh to new A-toh 7F. New phone number is ex. 8466, and fax number is 8469. 7.8 Long term schedules (0) Yohkoh recovery plan (1) Year-end and Year-begin Yohkoh operation ends at 29-Dec-01 5:18- 5:30 UT and resumes at 4-Jan-02 20:07-20:19 UT. (2) DASH Launch A piggyback mission DASH will be launched by HIIA at 3:00 UT, 31-Jan-02. Both 34m and 20m dishes at KSC will stand-by as ain and "hot-backup" systems from Y-9 to Y+3 days. A few schedule conflicts with Yohkoh operation will be adjusted at the next meeting in January. ------------------------------------------------------------------------------ 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 2000Jan. 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]