SSOC Tohban Report for Week 46 (12-Nov-2001 -- 18-Nov-2001) SSOC Tohbans : Y.Suematsu, K.Kumagai KSC Tohbans : T.Yokoyama, Kawano 0. Meeting Attendees T.Watanabe, Y.Ogawara, K.Matsuzaki, A.Takeda, D.Mchenzie, J.Sato K.Yoshimura, K.Kumagai, M.Kubo ------------------------------------------------------------------------------ 1. Solar Activity Activity has been moderately high, and there were 3M-class and approximately 10 C-class flares during the week. Although the activity is declining, NOAA 9697 and 9704 are growing and may raise activity level in a few days. ------------------------------------------------------------------------------- 2. Standard Operations 2.1 SXT Table Uploads The following SXT tables were uploaded: JST Day UT Start Time Pass Table ID ==================================================================== Monday AM 12-NOV-01 00:52 2 011111 P2 ARS1 STD* Tuesday AM 12-NOV-01 21:26 1 011112 P1 ARS1 DIFF Tuesday AM 13-NOV-01 02:29 4 011112 P4 ARS1 STD* Wednesday AM 13-NOV-01 21:21 1 011113 P1 ARS1 DARK Wednesday AM 14-NOV-01 02:24 4 011113 P4 ARS1 STD* Thursday AM 14-NOV-01 22:57 4 011114 P4 ARS1 STD Friday AM 15-NOV-01 22:52 2 011115 P2 ARS1 STD Saturday AM 16-NOV-01 22:48 3 011116 P3 ARS1 STD+LEO ==================================================================== 2.2 STT Timer Setting The STT timer was set at pass 2 on Tue 13-Nov-2001 (JST). ------------------------------------------------------------------------------- 3. Special Operation: 3.1 Second-round cheking of the Y-gyro performance At the first pass (011114-1443), the ACS control was changed to ACP SHD, and Y-gyro was turned on again for the first time since 11-Oct-01. A quick look of the real time data taken at the contact showed that the drift rate was estimated to an encouraging 13.8 deg/H, but seemed still accelerating for the first several minutes. SXT was set to CTL MAN, which disabled observations, but a long-duration M2 flare erupted between pass 1 and 2. Fortunately or unfortunately, the s/c was in SAA at its peak time, and s/c night started soon. We missed only a precursor phase, which, however, showed an interestingly complex X-ray flux enhancement in GOES light curve. At the second pass (011114-1546), Y-gyro was off, and S-gyro started to be used again. The ACS control was put back to CAQ (coarse aquisition) mode without difficulty. The Z-axis rotation excited by s/c nutation was estimated within 0.5 degree. The Y-gyro drift rate was estimated 16.0 - 16.3 deg/H. At the third pass (011115-0102), the ACS mode returned to FAQ (fine aquisition) and then NOR (normal operation). SXT also returned to CTL AT and restarted observations. However, the Z-axis had no Canopus in STT's tracking area. An 0.5 deg maneuver was performed. STT map data downlinked at pass 3 found Canopus 1.3 deg off. Canopus was still lost at the pass 4 (011115-0205). We made further an 0.8 deg maneuver around the Z-axis as prepared. A new standard SXT table was uploaded as scheduled. New STT map data were also checked after LOS, and we confirmed that the Z-gyro drift rate was stable during the test. At pass 5 (011115-0309), we confirmed that STT captured Canopus successfully. 3.2 HV Reduction for Leonidas Meteor Shower WBS, HXT, and BCS HV were reduced from 09h of 18 Nov. (UT) till pass 3 of 19 Nov. to avoid damage from the meteor shower and they were successfully resumed as scheduled. For this operation, OG-114 DAY (LEONIDS) and OG-115 HXT/WBS HV OFF were prepared and uploaded at pass 4 of 17 Nov. ------------------------------------------------------------------------------- 4. Errors and Problems 4.1 SXT Errors : None 4.2 DP Errors : None 4.3 BCS Errors : None ------------------------------------------------------------------------------- 5. NASA Station Schedule 5.1 Contact Pass Cancellations/Additions The following schedule changes occurred: ========================================================================= Week Schedule Changes ========================================================================= Real-Time 46 1 cancellations 0 additions requested Final 47 2 cancellations 0 additions requested Preliminary 48 2 cancellations 0 additions requested Strawman 49 85 cancellations ========================================================================= 5.2 Contacts this week and next (see 8.12): Week Wallops Santiago Goldstone Canberra Madrid NASA Japan 46 26 1 0 6 0 33 33 47 24 2 0 0 4 30 39 5.3 Data Transmission from NASA Ground Stations ----(Copied from /home/flare1/yohkoh/dsn_corrupt/2001/01_46)---- 283 66 0349 missing data requested 29-Oct 07-Nov Closed/ # We have received this data of 42078 frames on 1-Nov. 300 80 2310 not received requested 02-Nov no response 07-Nov Closed/ correct data 302 16 0219 missing data requested 12-Nov Closed/ same data 302 82 2121 corrupted tape requested 12-Nov Closed/ correct data 304 80 0040 corrupted tape requested 12-Nov Closed/ correct data 307 80 2101 corrupted tape requested 12-Nov Closed/ correct data 311 80 1358 corrupted tape requested 12-Nov Closed/ same data 305 w80 2251 - 2302: No Data: STATION POWER FAILURE. UNABLE TO TRACK. 311 G16 2212 - 2225: No Data: UNABLE TO LOCK TO TELEMETRY DATA, SIGNAL LEVEL WAS A -132DB AND DID NOT GET STRONGER THAN -124DB. THE STATION OPERATOR TRIED MANUAL TIME BIAS FORM A -10 SEC TO A +10 SEC WITHOUT SUCCESS. 302 74 2057 not received requested 07-Nov no response requested 12-Nov no response requested 14-Nov 305 82 1928 not received requested 12-Nov no response requested 14-Nov ------------------------------------------------------------------------------ 6. KSC Pass Conflicts and Schedule : No conflict : No conflict ------------------------------------------------------------------------------ 7. Hikitsugi Items 7.1 Tohbans for Next Week SSOC Tohbans : A. Takeda, M. Kubo KSC Tohbans : Kawano, Sekiguchi 7.2 STT Timer Setting The STT Timer Set is due on Tuesday 20-Nov-2001 (JST). 7.3 Holiday Schedule The next holiday is Sunday 25-Nov-2001 (JST). The 20m-antenna operations are scheduled for pass 2 (16:59 UT) and pass 5 (22:03 UT). These operations will be downlink only. 7.4 The OP and the command sheets for today The OP and command sheets for Monday (19 Nov 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. From W46, all DSN contacts should be made through WOTIS. 7.6 OG-114 and OG-115 OG-114 and OG-115 were modified for special operation against the Leonidas meteor shower damage. Recovered OG-114 and OG-115 will be uploaded at pass 1(011119-1239) of 20 Nov. 7.7 SXT tohban contact The SXT tohban has moved from D-toh to A-toh. New phone number is ex. 6162, and temporary fax number is 8526. 7.8 Long term schedules (1) 34m RaNGing Testing A few number of DC uplinks from the 34m system and downlinks via the 20m system will be possible in the following two passes dedicated to the testing. 11-Dec-01 13:51-14:04UT and 12-Dec-01 12:04-12:18UT (2) Year-end and Year-begin Yohkoh operation ends at 29-Dec-01 5:18- 5:30UT and resumes at 4-Jan-02 20:07-20:19UT. (3) DASH Launch A piggyback mission DASH will be launched by HIIA at 3:00UT 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 operataion 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 alculation 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]