Update for (181) Eucharis - August 8/9, 2003

Jan Manek's update

                 IOTA/IOTA-ES occultation update for
         (181) Eucharis / TYC 5262-00900-1 on August 8/9, 2003
         visible from Belarus, W Ukraine, Romania, W Bulgaria,
                       Greece and Libya

Summary 

In the night of August 8/9, 2003 a faint 11.5 mag star TYC 5262-00900-1 will be occulted by a 107 km asteroid (181) Eucharis. This update is based on USNO/Flagstaff and La Silla astrometry for the asteroid and UCAC2-beta star position.

The updated path shows ~2.5 path width east shift with time ~0.5 minutes later compared to Edwin Goffin's nominal prediction.

Updated path runs due to east shift over Belarus ~2:00.4 UT with Minsk on east limit with Sun only 5 degrees below horizon, W Ukraine ~2:00.6 UT, Romania ~2:01.2 UT, W Bulgaria ~2:01.6 UT with Sofia in path, Greece ~2:02.1 UT and Libya ~2:03.0 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: August 9, 2003 @ 02.02 UT
 * magnitude of target star: 11.5
 * magnitude drop [mag]: 1.8
 * estimated maximum duration [s]: 11.3
 * path description: given above
 * Goffin's original chart reference: A03_0816

The occultation path:
 * approximate ground width [km]: 110
 * uncertainty [path widths]: 1.05
 * uncertainty in time [s]: 12
 * 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 5262-00900-1
 * constellation: Cetus
 * J2000 position [h,m,s; o,',"]: 00h 23m 59.5249s; -09o 12' 13.303"
 * position source: recent UCAC2 beta
 * estimated accuracy ["]: 0.03" (0.02", 0.02")
 * V mag [mag]: 10.53
 * B-V [mag]: +0.67
 * remarks:
    Target star is in middle west Cetus, about 1.3 degrees east of 3.5 mag star iota Ceti = SAO 128694.
    Only 7' south of target is mira variable S Ceti.
    !!! 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: (181) Eucharis
     approx. diameter [km]: 107
 * orbital information
     orbit source: calculation Manek
     source of used astrometry: USNO/Flagstaff (Ron Stone), La Silla (Raoul Behrend)
     number of used observations: 104 USNO, 3 La Silla
     number of rejected observations: 0
     time covered by the observations: 1998 09 13 - 2003 07 26
     rms residuals ["] (RA,DE): 0.08", 0.10"
     estimated positional accuracy at epoch of event ["]: 0.06", 0.06"
     remarks:

Data for the event:
 * UT date and time of least geocentric approach: 02:10.4 UT
 * approx. V mag of minor planet at event [mag]: 13.1
 * geocentric parallax of minor planet ["]: 3.575
 * magnitude drop [mag]: 1.8
 * estimated maximum duration [s]: 11.3
 * apparent motion of minor planet ["/h]: 19.08
 * angular distance to moon, phase of moon [deg,%]: 85, 88%
 * remarks:

Elements for WinOccult:
============ cut here ===========================================
 2003 Aug 09
181 Eucharis
 2h 10.4m UT
62-00900-1  11.5    0 23 59.525- 9 12 13.30TYC 5262-00900-1
13.1    107   11.3   2.460    -0.178    -18.91
 -343.772  -9.198  -211.19   16.01
  2.1734  -.04112   .00594 -0.73256 -5.28733 -0.00399 -0.00094
2000    269.8885562003 730.00000316.827815143.71613218.814934 0.198004003.137324822.516121967.845   0.15
RATE 1.7736370 .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  '  "
     29  0  0    60 17 33    1 59 54    20   191    -1   62 38  6   57 59 27   67 42 26   53 16 20
     28  0  0    57 47 40    2  0  5    23   190    -3   60 15 59   55 22 20   65 38 51   50 25 28
     27  0  0    54 57 35    2  0 19    26   189    -5   57 33 38   52 25 10   63 15 19   47 14 59
     26  0  0    51 45 13    2  0 36    29   188    -7   54 28 35   49  6  9   60 28 32   43 43 40
     25  0  0    48  8 59    2  0 58    33   187   -10   50 58 48   45 24  6   57 15 20   39 50 57
     24  0  0    44  8  8    2  1 25    37   187   -13   47  3  6   41 18 39   53 33 11   35 37  3
     23  0  0    39 43 13    2  1 58    41   186   -16   42 41 38   36 50 39   49 20 55   31  3 13
     22  0  0    34 56 12    2  2 37    46   185   -20   37 56  8   32  2 11   44 39 27   26 11 40
     21  0  0    29 50 23    2  3 22    51   185   -23   32 49 59   26 56 31   39 32  1   21  5 30
     20  0  0    24 30  7    2  4 12    56   184   -27   27 27 46   21 37 42   34  3 55   15 48 21
     19  0  0    19  0 12    2  5  8    62   183   -31   21 54 44   16 10 15   28 21 39   10 24 11
     18  0  0    13 25 28    2  6  8    67   182   -34   16 16  9   10 38 37   22 31 48    4 56 58
    ...................................... 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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