Update for (790) Pretoria - November 7/8, 2003

Jan Manek's update

                  IOTA/IOTA-ES occultation update for
         (790) Pretoria / TYC 1742-00707-1 on November 7/8, 2003
                     visible from Ireland and Brasil


Summary 

In the night of November 7/8, 2003 a faint 11.0 mag star TYC 1742-00707-1 will be occulted by a 176 km asteroid (790) Pretoria. This update is based on USNO/Flagstaff, TMO and Ondrejov astrometry for the asteroid and UCAC2 star position.

The updated path shows ~0.5 path width east shift with time ~0.7 later earlier compared to Edwin Goffin's nominal prediction.

Updated path runs due to east shift closer to Europe and just grazes west coast of Ireland ~21:09.0 UT and later runs over Brazil ~21:16.5 UT. Please check the path chart for details.

Clear sky and good luck !!!

The event at one glimpse:
 * date and approx. UT time of event: November 7, 2003 @ 21:09 UT (Europe)
 * magnitude of target star: 11.0
 * magnitude drop [mag]: 2.3
 * estimated maximum duration [s]: 12.5
 * path description: given above
 * Goffin's original chart reference: A03_1131

The occultation path:
 * approximate ground width [km]: 195
 * uncertainty [path widths]: 0.5
 * uncertainty in time [s]: 7
 * map: below
 * remarks: Path uncertainties are given according to nominal star
    position errors and expected asteroid positional accuracy.

Data for the target star:
 * name: TYC 1742-00707-1
 * constellation: Pisces
 * J2000 position [h,m,s; o,',"]: 00h 51m 28.5941s; +26o 57' 15.776"
 * position source: UCAC2
 * estimated accuracy ["]: 0.02" (0.02", 0.02")
 * V mag [mag]: 11.04
 * B-V [mag]: +0.51
 * remarks:
    Target star is in north Pisces, about 4.7 degrees south of 3.3 mag star delta Andromedae = SAO 54058.
    !!! IMPORTANT !!!
    Purple stars in identification chart are so called 'non-star' objects in GSC; in dense fields
    the 'non-stars' are often real stars or blends of close pairs. Be careful about this.

Close finding chart (prepared in GUIDE8):
 * occulted star is in center - labeled with cross
 * field is 3.0x3.0 degrees
 * limiting magnitude is 13.0
 * labeled stars have indicated SAO numbers
 * remarks: Second chart shows 30' blowup to show correctly the star in field.










Data for the minor planet:
 * general information:
     number, name: (790) Pretoria
     approx. diameter [km]: 176
 * orbital information
     orbit source: calculation Manek
     source of used astrometry: USNO/Flagstaff (Ron Stone), TMO (Bill Owen), Ondrejov (Manek)
     number of used observations: 153 USNO, 36 TMO, 11 Ondrejov
     number of rejected observations: 12 USNO, 1 TMO
     time covered by the observations: 1997 09 29 - 2003 10 27
     rms residuals ["] (RA,DE): 0.07", 0.08"
     estimated positional accuracy at epoch of event ["]: 0.05", 0.05"
     remarks:

Data for the event:
 * UT date and time of least geocentric approach: 21:11.2 UT
 * approx. V mag of minor planet at event [mag]: 13.2
 * geocentric parallax of minor planet ["]: 3.550
 * magnitude drop [mag]: 2.3
 * estimated maximum duration [s]: 12.5
 * apparent motion of minor planet ["/h]: 28.19
 * angular distance to moon, phase of moon [deg,%]: 23, 99%
 * remarks:

Elements for WinOccult:
============ cut here ===========================================
 2003 Nov 07
  790  Pretoria
21h 11.2m UT
  11.0    0 51 28.594 26 57 15.78TYC 1742-00707-1      11.6
13.2    176   12.5   2.477    -1.129    -23.81
    8.407  26.961   218.12  -16.35
 21.1870  -.35672   .22611 -4.25536 -6.70509  0.00283 -0.00075
2000    77.2275267200311 7.0000040.592243 252.17562520.542954 0.150195493.411414582.899035488.005   0.15
RATE 1.5642362 .0000000 .0000000 .0000000 .00000000 .00000000 .00000000
============ cut here ===========================================

Calculator(s): Jan Manek










Path coordinates:
                  Centre              Star  Star   Sun      Path Limits           Error Limits
  E. Longitude   Latitude      U.T.    Alt    Az   Alt    Limit 1    Limit 2    Limit 3    Limit 4
    ...................................... shortened .............................................
      o  '  "     o  '  "    h  m  s     o     o     o    o  '  "    o  '  "    o  '  "    o  '  "
                                                         Latitude   Latitude   Latitude   Latitude
     15  0  0    81 20 48   21  6  0    36   186   -24   83 24 57   79 21 39   85 42 55   77 20  1
     13  0  0    80 40  0   21  6  4    36   184   -25   82 52 16   78 33 43   85 20 19   76 25 25
     11  0  0    79 52 30   21  6  8    37   181   -25   82 13 50   77 38 27   84 53 21   75 22 59
      9  0  0    78 56 54   21  6 13    38   179   -26   81 28 13   76 34 28   84 20 46   74 11 24
      7  0  0    77 51 26   21  6 20    39   177   -26   80 33 37   75 20  4   83 40 51   72 49  5
      5  0  0    76 33 57   21  6 27    40   175   -27   79 27 44   73 53 21   82 51 19   71 14 20
      3  0  0    75  1 59   21  6 37    42   172   -28   78  7 43   72 12 10   81 48 59   69 25 18
      1  0  0    73 12 45   21  6 48    43   169   -29   76 30 10   70 14 14   80 29 40   67 20 10
   -  1  0  0    71  3 27   21  7  2    45   167   -30   74 31 16   67 57 26   78 48  0   64 57 17
   -  3  0  0    68 31 37   21  7 18    48   163   -31   72  7 22   65 20  2   76 38  1   62 15 29
   -  5  0  0    65 35 41   21  7 38    50   160   -33   69 15 44   62 21 10   73 54 18   59 14 18
   -  7  0  0    62 15 32   21  8  2    53   155   -34   65 55 32   59  1  4   70 34  8   55 54 15
   -  9  0  0    58 32 47   21  8 29    56   150   -35   62  8 25   55 21 20   66 39 12   52 16 51
   - 11  0  0    54 30 39   21  9  0    59   144   -36   57 58 24   51 24 42   62 15 27   48 24 34
   - 13  0  0    50 13 27   21  9 33    61   136   -37   53 31  1   47 14 48   57 31  7   44 20 32
   - 15  0  0    45 45 58   21 10  9    63   126   -37   48 52 14   42 55 41   52 34 30   40  8 17
   - 17  0  0    41 12 52   21 10 47    65   116   -37   44  7 39   38 31 22   47 32 43   35 51 22
   - 19  0  0    36 38 20   21 11 24    65   104   -36   39 22  3   34  5 34   42 31 17   31 33  5
   - 21  0  0    32  5 55   21 12  2    64    93   -35   34 39 16   29 41 32   37 34 19   27 16 27
   - 23  0  0    27 38 26   21 12 39    62    84   -33   30  2 19   25 21 58   32 44 50   23  3 58
   - 25  0  0    23 18 10   21 13 14    60    76   -31   25 33 26   21  9  1   28  4 54   18 57 44
   - 27  0  0    19  6 45   21 13 48    57    69   -29   21 14 15   17  4 21   23 36  0   14 59 21
   - 29  0  0    15  5 26   21 14 19    54    65   -26   17  5 55   13  9 13   19 19  5   11 10  4
   - 31  0  0    11 15  0   21 14 49    50    61   -24   13  9 10    9 24 27   15 14 44    7 30 43
   - 33  0  0     7 35 58   21 15 15    47    58   -21    9 24 25    5 50 36   11 23 13    4  1 52
   - 35  0  0     4  8 34   21 15 40    44    56   -18    5 51 50    2 27 56    7 44 34    0 43 51
   - 37  0  0     0 52 48   21 16  2    40    54   -16    2 31 22  - 0 43 29    4 18 39  - 2 23 18
   - 39  0  0   - 2 11 27   21 16 21    37    53   -13  - 0 37 10  - 3 43 45    1  5 13  - 5 19 36
   - 41  0  0   - 5  4 28   21 16 39    34    53   -10  - 3 34  5  - 6 33  6  - 1 56  9  - 8  5 18
   - 43  0  0   - 7 46 35   21 16 54    30    52    -8  - 6 19 46  - 9 11 51  - 4 45 52  -10 40 41
   - 45  0  0   -10 18 14   21 17  7    27    52    -5  - 8 54 41  -11 40 24  - 7 24 27  -13  6  7
    ...................................... shortened .............................................

----------------------------------------------------------------------------
Jan Manek
Stefanik Observatory                Private :
Petrin 205                          Werichova 950
118 46  Praha 1                     152 00  Praha 5 - Barrandov     |_|_|
Czech Republic                      Czech Republic                  /   \
Internet : jan.manek@worldonline.cz                                |-O-O-|
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