Update for (309) Fraternitas - November 4, 2002

Jan Manek's update

                    IOTA/IOTA-ES occultation update for
         (309) Fraternitas / HIP 35494 = SAO 79286 on November 4, 2002
          visible from NW Italy, E Switzerland, W Austria, E Germany,
                        W Czechia, W Poland and Sweden

Summary 

In the evening of November 4, 2002 a bright 7.0 mag star HIP 35494 = SAO 79286 will be occulted by a 55 km asteroid (309) Fraternitas. This update is based on USNO/Flagstaff and TMO astrometry for the asteroid and Hipparcos star position.

The updated path shows large ~0.7" NW shift with time ~0.8 minutes earlier compared to Edwin Goffin's nominal prediction.

Updated path runs over NW Italy ~20:41.5 UT, E Switzerland and W Austria ~20:41.2 UT, SE Germany with Munich ~20:42.8 UT, W Czechia ~20:43.2 UT and goes to north along Germany-Poland border still with Berlin in path 20:44.8 UT and finally Sweden 20:47 to 20:51 UT. Fine event due to bright star and long event duration. Don't miss it. 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 4, 2002 @ 20:44 UT
 * magnitude of target star: 7.0
 * magnitude drop [mag]: 8.5
 * estimated maximum duration [s]: 17.8
 * path description: given above
 * Goffin's original chart reference: A02_1118

The occultation path:
 * approximate ground width [km]: 170
 * uncertainty [path widths]: 2.0
 * uncertainty in time [s]: 36
 * map: below
 * remarks: Path uncertainties are given according to nominal star
    position errors and expected asteroid positional accuracy.

Data for the target star:
 * name: HIP 35494 = SAO 79286 = PPM 973715 = TYC 1917-00859-1
 * constellation: Gemini
 * J2000 position [h,m,s; o,',"]: 07h 19m 30.7705s; +26o 49' 22.501"
 * position source: Hippparcos
 * estimated accuracy ["]: 0.02" (0.02", 0.01")
 * V mag [mag]: 6.96
 * B-V [mag]: +0.97
 * remarks:
    Target star is in mid-east Gemini, about 1.7 degrees southwest of 3.8 mag star iota Geminorum = SAO 79374.
    !!! 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 GUIDE7):
 * occulted star is in center - labeled with cross
 * field is 4.0x4.0 degrees
 * limiting magnitude is 11.5
 * labeled stars have indicated SAO numbers
 * remarks:





Data for the minor planet:
 * general information:
     number, name: (309) Fraternitas
     approx. diameter [km]: 55
 * orbital information
     orbit source: calculation Manek
     source of used astrometry: USNO/Flagstaff (Ron Stone), TMO (Bill Owen)
     number of used observations: 71 USNO, 11 TMO
     number of rejected observations: 6 USNO
     time covered by the observations: 1997 10 21 - 2002 10 09
     rms residuals ["] (RA,DE): 0.09", 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: 20:52.3 UT
 * approx. V mag of minor planet at event [mag]: 15.5
 * geocentric parallax of minor planet ["]: 3.760
 * magnitude drop [mag]: 8.5
 * estimated maximum duration [s]: 17.8
 * apparent motion of minor planet ["/h]: 6.57
 * angular distance to moon, phase of moon [deg,%]: 114, 0%
 * remarks:

Elements for WinOccult:
============ cut here ===========================================
 2002 Nov 04
309 Fraternitas
20h 52.3m UT
HIP 35494    7.0    7 19 30.771 26 49 22.50
15.5     55   17.8   2.339     0.442      2.81
 -247.117  26.823  -137.17  -15.52
 20.8712  -.40007   .85094  1.58025  0.74628 -0.00536  0.00053
2000    133.074495200211 2.00000310.469463356.6760283.720829  0.115173672.664981872.3580461410.45   0.15
RATE 2.2654920 .0000000 .0000000 .0000000 .00000000 .00000000 .00000000
============ cut here ===========================================


Calculator(s): Jan Manek





Path coordinates:

                  Center               Altitude       Path Limits
  E. Longitude   Latitude      U.T.   star   sun   Limit 1    Limit 2
   ........................... shortened .............................
      o  '  "     o  '  "    h  m  s     o     o    o  '  "    o  '  "
                                                  Longitude  Longitude
      5 31 29    42  0  0   20 40 57     4   -47    6 58 19    3 59 23
      6 46  1    43  0  0   20 41 10     5   -47    8  9 53    5 17 32
      7 53 23    44  0  0   20 41 25     7   -47    9 14 58    6 27 40
      8 54 24    45  0  0   20 41 42     8   -47   10 14 13    7 30 48
      9 49 41    46  0  0   20 42  2     9   -47   11  8 10    8 27 41
     10 39 41    47  0  0   20 42 23    10   -47   11 57 13    9 18 52
     11 24 45    48  0  0   20 42 46    11   -47   12 41 38   10  4 44
     12  5  8    49  0  0   20 43 10    12   -47   13 21 40   10 45 36
     12 41  1    50  0  0   20 43 35    13   -47   13 57 27   11 21 40
     13 12 31    51  0  0   20 44  2    14   -46   14 29  5   11 53  4
     13 39 40    52  0  0   20 44 29    14   -46   14 56 37   12 19 52
     14  2 29    53  0  0   20 44 58    15   -45   15 20  3   12 42  5
     14 20 56    54  0  0   20 45 27    16   -45   15 39 20   12 59 40
     14 34 53    55  0  0   20 45 58    16   -44   15 54 23   13 12 30
     14 44 13    56  0  0   20 46 29    17   -44   16  5  4   13 20 24
     14 48 41    57  0  0   20 47  1    17   -43   16 11  9   13 23 10
     14 48  2    58  0  0   20 47 34    18   -42   16 12 24   13 20 27
     14 41 52    59  0  0   20 48  7    18   -42   16  8 29   13 11 52
     14 29 45    60  0  0   20 48 41    18   -41   15 59  0   12 56 55
     14 11  7    61  0  0   20 49 16    19   -40   15 43 26   12 34 57
     13 45 15    62  0  0   20 49 51    19   -39   15 21  8   12  5  8
     13 11 14    63  0  0   20 50 27    19   -38   14 51 19   11 26 28
                                                   Latitude   Latitude
     12  0  0    64 32 37   20 51 24    19   -37   66 22  8   62  8 53
     11  0  0    65 32  2   20 52  2    19   -36   67  8 50   63 34 11
     10  0  0    66 21 16   20 52 34    19   -35   67 49  7   64 38 39
      9  0  0    67  3 23   20 53  3    19   -34   68 24 29   65 31  5
   ........................... 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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