Update for (379) Huenna - July 22/23, 2003

Jan Manek's update

                    IOTA/IOTA-ES occultation update for
            (379) Huenna / TYC 0025-00703-1 on July 22/23, 2003
              visible from west Africa, Egypt and middle East

Summary 

In the night of July 22/23, 2003 a faint 10.7 mag star TYC 0025-00703-1 will be occulted by a 96 km asteroid (379) Huenna. This update is based on USNO/Flagstaff and La Silla astrometry for the asteroid and UCAC2-beta star position.

The updated path shows ~3.5 path width south shift with time ~1.7 minutes later compared to Edwin Goffin's nominal prediction.

Updated path runs due to south shift over west Africa 21:27-21:30 UT, Egypt ~21:31 UT and middle East ~21:32 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: July 23, 2003 @ 00:31 UT
 * magnitude of target star: 10.7
 * magnitude drop [mag]: 3.0
 * estimated maximum duration [s]: 8.0
 * path description: given above
 * Goffin's original chart reference: A03_0733

The occultation path:
 * approximate ground width [km]: 120
 * uncertainty [path widths]: 1.0
 * uncertainty in time [s]: 8
 * 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 0025-00703-1
 * constellation: Pisces
 * J2000 position [h,m,s; o,',"]: 01h 01m 32.5938s; +06o 30' 30.637"
 * position source: recent UCAC2 beta
 * estimated accuracy ["]: 0.03" (0.02", 0.02")
 * V mag [mag]: 10.70
 * B-V [mag]: +1.05
 * remarks:
    Target star is in middle Pisces, about 1.4 degrees SSW of 4.3 mag star epsilon Piscii = SAO 109627.
    !!! 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 4.0x4.0 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: (379) Huenna
     approx. diameter [km]: 96
 * orbital information
     orbit source: calculation Manek
     source of used astrometry: USNO/Flagstaff (Ron Stone), La Silla (Raoul Behrend)
     number of used observations: 84 USNO, 3 Behrend
     number of rejected observations: 6 USNO
     time covered by the observations: 1998 09 24 - 2003 07 10
     rms residuals ["] (RA,DE): 0.08", 0.08"
     estimated positional accuracy at epoch of event ["]: 0.06", 0.06"
     remarks:

Data for the event:
 * UT date and time of least geocentric approach: 00:34.2 UT
 * approx. V mag of minor planet at event [mag]: 13.6
 * geocentric parallax of minor planet ["]: 4.186
 * magnitude drop [mag]: 3.0
 * estimated maximum duration [s]: 8.0
 * apparent motion of minor planet ["/h]: 28.45
 * angular distance to moon, phase of moon [deg,%]: 32, 34%
 * remarks:

Elements for WinOccult:
============ cut here ===========================================
 2003 Jul 23
379 Huenna
 0h 34.2m UT
25-00703-1  10.7    1  1 32.594  6 30 30.64TYC 0025-00703-1
13.6     96    8.0   2.101     1.797      9.55
 -293.509   6.506  -186.93   20.19
  0.5699  -.17895   .50529  6.39733  2.28304 -0.00493 -0.00204
2000    0.255934922003 720.00000180.190353172.2797871.668239550.191697083.131405722.531124398.865   0.15
RATE 1.7786687 .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
                                                         Latitude   Latitude   Latitude   Latitude
    ...................................... shortened .............................................
      o  '  "     o  '  "    h  m  s     o     o     o    o  '  "    o  '  "    o  '  "    o  '  "
   - 14  0  0    14  6 44    0 26 51     9    85   -55   13 35 20   14 38 20   13 35 20   14 38 20
   - 12  0  0    14 28 59    0 26 55    11    86   -55   13 57 30   15  0 40   13 57 30   15  0 40
   - 10  0  0    14 52 52    0 27  0    13    87   -55   14 21 17   15 24 38   14 21 17   15 24 38
   -  8  0  0    15 18 20    0 27  5    15    87   -54   14 46 39   15 50 13   14 46 39   15 50 13
   -  6  0  0    15 45 24    0 27 11    17    88   -54   15 13 37   16 17 23   15 13 37   16 17 23
   -  4  0  0    16 14  2    0 27 18    19    88   -54   15 42  8   16 46  7   15 42  8   16 46  7
   -  2  0  0    16 44 11    0 27 25    21    89   -53   16 12 11   17 16 23   16 12 11   17 16 23
      0  0  0    17 15 49    0 27 33    23    90   -52   16 43 42   17 48  8   16 43 42   17 48  8
      2  0  0    17 48 55    0 27 42    25    91   -51   17 16 41   18 21 21   17 16 41   18 21 21
      4  0  0    18 23 26    0 27 52    27    92   -50   17 51  5   18 55 59   17 51  5   18 55 59
      6  0  0    18 59 19    0 28  2    28    93   -49   18 26 51   19 31 59   18 26 51   19 31 59
      8  0  0    19 36 31    0 28 13    30    94   -48   19  3 56   20  9 18   19  3 56   20  9 18
     10  0  0    20 14 59    0 28 25    32    95   -47   19 42 16   20 47 53   19 42 16   20 47 53
     12  0  0    20 54 39    0 28 37    34    96   -46   20 21 49   21 27 41   20 21 49   21 27 41
     14  0  0    21 35 27    0 28 49    36    98   -44   21  2 31   22  8 37   21  2 31   22  8 37
     16  0  0    22 17 20    0 29  3    38    99   -43   21 44 17   22 50 37   21 44 17   22 50 37
     18  0  0    23  0 14    0 29 17    39   101   -41   22 27  4   23 33 37   22 27  4   23 33 37
     20  0  0    23 44  3    0 29 31    41   103   -40   23 10 46   24 17 33   23 10 46   24 17 33
     22  0  0    24 28 43    0 29 46    43   104   -38   23 55 20   25  2 20   23 55 20   25  2 20
     24  0  0    25 14 10    0 30  1    44   106   -36   24 40 41   25 47 52   24 40 41   25 47 52
     26  0  0    26  0 17    0 30 17    46   109   -34   25 26 42   26 34  5   25 26 42   26 34  5
     28  0  0    26 47  0    0 30 33    47   111   -33   26 13 20   27 20 53   26 13 20   27 20 53
     30  0  0    27 34 13    0 30 49    49   114   -31   27  0 28   28  8 11   27  0 28   28  8 11
     32  0  0    28 21 50    0 31  6    50   116   -29   27 48  1   28 55 53   27 48  1   28 55 53
     34  0  0    29  9 47    0 31 23    51   119   -27   28 35 54   29 43 54   28 35 54   29 43 54
     36  0  0    29 57 57    0 31 40    53   122   -26   29 24  0   30 32  7   29 24  0   30 32  7
     38  0  0    30 46 14    0 31 57    54   125   -24   30 12 15   31 20 27   30 12 15   31 20 27
     40  0  0    31 34 33    0 32 14    54   129   -22   31  0 32   32  8 48   31  0 32   32  8 48
     42  0  0    32 22 48    0 32 32    55   132   -20   31 48 45   32 57  5   31 48 45   32 57  5
     44  0  0    33 10 53    0 32 49    56   136   -18   32 36 49   33 45 11   32 36 49   33 45 11
     46  0  0    33 58 44    0 33  6    57   140   -16   33 24 40   34 33  2   33 24 40   34 33  2
     48  0  0    34 46 14    0 33 24    57   144   -14   34 12 10   35 20 32   34 12 10   35 20 32
     50  0  0    35 33 19    0 33 41    57   148   -13   34 59 16   36  7 36   34 59 16   36  7 36
     52  0  0    36 19 53    0 33 58    57   152   -11   35 45 51   36 54  9   35 45 51   36 54  9
     54  0  0    37  5 53    0 34 15    57   156    -9   36 31 53   37 40  6   36 31 53   37 40  6
     56  0  0    37 51 12    0 34 32    57   160    -7   37 17 15   38 25 23   37 17 15   38 25 23
    ...................................... 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-|
--------------------------------------------------------------------U---U---