Update for (222) Lucia - September 26, 2000

Jan Manek's update

                    IOTA/IOTA-ES occultation update for
       (222) Lucia/ HIP 98948 = SAO 188896 on September 26, 2000
       visible from Czechia, Slovakia, Poland, Belarus and Russia


Summary 

In the evening of September 26, 2000 a 9.1 mag star HIP 98948 = SAO 188896 will be occulted by a small 58 km asteroid (222) Lucia. This update is based on USNO/Flagstaff astrometry for the asteroid and Hipparcos star position.

The updated path shows no significant path shift with time ~0.8 minutes earlier compared to Edwin Goffin's nominal prediction.

The path of this occultation runs over SE Czech ~17:08 UT in strong twilight, NW Slovakia and SE Poland around 17:09 UT from SW to NE. Later Belarus ~17:10.5 UT and NW Russia ~17:11 UT is in path. Conditions are not very favorable in the eastern part where event takes place very early after sunset and there will not be probably enough time for locating the star. On the other hand in Poland (and mostly in it's NE part) the situation gets better.

Keep in mind the full 3 path width uncertainty, which rises possibility to see this event from whole Poland and Slovakia, whole Hungary ~17:08 UT and western parts of Ukraine 17:09-17:10 UT.

Please follow central line circles - it is more reliable than path limits.

The event at one glimpse:
 * date and approx. UT time of event: September 26, 2000 @ 17:08 UT (Europe)
 * magnitude of target star: 9.1
 * magnitude drop [mag]: 5.0
 * estimated maximum duration [s]: 9.7
 * path description: given above
 * Goffin's original chart reference: A00_0912

The occultation path:
 * approximate ground width [km]: 210
 * uncertainty [path widths]: 3
 * uncertainty in time [s]: 30
 * map: below
 * remarks: Path uncertainities are given according to nominal star
    position errors and expected asteroid positional accuracy.
    !!!!!!!
    Circles along path indicates the centerline for this event.
    They are more accurate than the path limit lines.
    !!!!!!!

Data for the target star:
 * name: HIP 98948 = SAO 188896 = PPM 270673 = TYC 6892-00192-1
 * constellation: Sagittarius
 * J2000 position [h,m,s; o,',"]: 20h 05m 22.273s; -22o 37' 55.47"
 * position source: Hipparcos
 * estimated accuracy ["]: 0.02" (0.01", 0.01")
 * V mag [mag]: 9.14
 * B-V [mag]: +0.30
 * remarks: 
     Target star is in eastern Sagittarius, quite far from bright stars.
     There is 3.1 mag star beta Capricorni ~9 degrees NE of target and also
     globular cluster M75 about 44' north of target. About 55' west of 
     target is 6.0 mag star SAO 188829 and 23' west of target is 6.4 mag 
     star SAO 188863.

Close finding chart (prepared in GUIDE7):
 * occulted star is in center - labeled with cross
 * field is 3.0x3.0 degrees
 * limiting magnitude is 12.5
 * labeled stars have indicated SAO numbers





Data for the minor planet:
 * general information:
     number, name: (222) Lucia
     approx. diameter [km]: 58
 * orbital information
     orbit source: calculation Manek
     source of used astrometry: USNO/Flagstaff (Ron Stone)
     number of used observations: 54 USNO
     number of rejected observations: 6 USNO
     time covered by the observations: 1998 02 17 - 2000 09 17
     rms residuals ["] (RA,DE): 0.10", 0.10"
     estimated positional accuracy at epoch of event ["]: 0.10"
     remarks: 

Data for the event:
 * UT date and time of least geocentric approach: 17:07.4 UT
 * approx. V mag of minor planet at event [mag]: 14.1
 * geocentric parallax of minor planet ["]: 3.857
 * magnitude drop [mag]: 5.0
 * estimated maximum duration [s]: 9.7
 * apparent motion of minor planet ["/h]: 13.04
 * angular distance to moon, phase of moon [deg,%]: 131, 2%
 * remarks: 

Calculator(s): Jan Manek








Path coordinates:
                                       Altitude
  E. Longitude    Latitude     U.T.    star  sun
   ........ shortened ..........................
      o  '  "      o  '  "    h  m  s    o     o
     14  0  0    48 12 10   17  7 20    16    -3
     15  0  0    48 30 37   17  7 34    16    -4
     16  0  0    48 50 41   17  7 48    16    -5
     17  0  0    49 12 24   17  8  3    16    -5
     18  0  0    49 35 49   17  8 17    16    -6
     19  0  0    50  1  0   17  8 32    15    -7
     20  0  0    50 28  0   17  8 47    15    -7
     21  0  0    50 56 55   17  9  1    15    -8
     22  0  0    51 27 49   17  9 16    15    -8
     23  0  0    52  0 49   17  9 30    14    -9
     24  0  0    52 36  2   17  9 45    14   -10
     25  0  0    53 13 40   17  9 59    13   -10
     26  0  0    53 53 53   17 10 13    13   -11
     27  0  0    54 36 58   17 10 27    12   -11
     28  0  0    55 23 14   17 10 41    12   -11
     29  0  0    56 13  9   17 10 55    11   -12
     30  0  0    57  7 22   17 11  8    10   -12
     31  0  0    58  6 50   17 11 21     9   -12
     32  0  0    59 13  7   17 11 33     8   -12
     33  0  0    60 28 57   17 11 46     7   -13
   ........ shortened ..........................

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