Update for (372) Palma - August 6/7, 2000

Jan Manek's update

                    IOTA/IOTA-ES occultation update for
       (372) Palma / HIP 11333 = SAO 55544 event on August 6/7, 2000
     visible from NW Africa, Spain, W France, SE England and W Belgium


Summary 

In the morning of August 6/7, 2000 a bright 7.3 mag star HIP 11333 = SAO 55544 will be occulted by a large 195 km asteroid (372) Palma. This update is based on USNO/Flagstaff, TMO and Stefanik Observatory astrometry for the asteroid and modified Hipparcos star position.

The updated path shows large ~0.5" NW shift with time ~0.5 minutes later compared to Edwin Goffin's nominal prediction. Due to the large shift wrt. to Goffin's nominal prediction using fresh orbit, I've asked Martin Federspiel to check my results and he fully confirmed my finding of this large shift.

The path of this occultation runs over NW Africa with last African country being Morocco ~3:24 UT. Path runs north to Spain over Gibraltar ~3:24.5 UT into middle Spain with Madrid ~3:25.0 UT and Pamplona ~3:25.3 UT. Observatory Pic du Midi is on the east limit at the same time. Later centerline runs along atlantic coast of south France with Bordeaux in path ~3:25.5 UT. Then path gets more into midland, runs over Tours ~3:25.6 UT, Paris is in path close to eastern border ~3:25.8 UT. Western part of Belgium is in path shortly before 3:26.0 UT and at the same time eastern limit runs over very east England and later eastern limit runs over western Netherlands. In strong twilight the path finaly runs over southern Norway ~3:27 UT.

Considering the 1 path width uncertainity many other places have chance - London is less than 0.5 path width west of west limit while Bruxelles is just out of east limit.

As the star is quite bright, high in the sky and event has large brightness drop, this is a very good opportunity for many people. Good binocular on tripod will be sufficient! Try to organise groups for better coverage of the profile and alert observers within your reach to let them try.

Good luck !!!

The event at one glimpse:
 * date and approx. UT time of event: August 7, 2000 @ 03:25 UT
 * magnitude of target star: 7.3
 * magnitude drop [mag]: 5.0
 * estimated maximum duration [s]: 8.3
 * path description: given above
 * Goffin's original chart reference: A00_0817

The occultation path:
 * approximate ground width [km]: 220
 * uncertainty [path widths]: 1.0
 * uncertainty in time [s]: 10
 * 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 11333 = SAO 55544 = PPM 67322 = TYC 2333-1107-1
 * constellation: Triangulum
 * J2000 position [h,m,s; o,',"]: 02h 25m 49.942s; +37o 00' 49.24"
 * position source: Hipparcos
 * estimated accuracy ["]: 0.01 (0.01", 0.01")
 * V mag [mag]: 7.28
 * B-V [mag]: +1.69
 * remarks: 
     Target star is in very north Triangulum, close to border with Andromeda.
     Famous triple star 2.2 mag gamma Andromedae is 6.8 degrees NW of target
     and 3.0 mag beta Trianguli is 3.8 degrees SW of target. Target star is
     very red and this should be easily found compared to 7.3 mag blue star
     SAO 55530 which is only 9' NW of target.

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: (372) Palma
     approx. diameter [km]: 195
 * orbital information
     orbit source: calculation Manek
     source of used astrometry: USNO/Flagstaff (Ron Stone), TMO (Bill Owen),
                                Stef.Obs (Jan Manek)
     number of used observations: 21 USNO, 3 TMO, 2 Stef.Obs
     number of rejected observations: 5 USNO
     time covered by the observations: 1999 06 22 - 2000 08 01
     rms residuals ["] (RA,DE): 0.06", 0.08"
     estimated positional accuracy at epoch of event ["]: 0.10"
     remarks: There only few this year's positions, so estimated accuracy
       is somewhat larger than RMS values of solution.

Data for the event:
 * UT date and time of least geocentric approach: 03:25.7  UT
 * approx. V mag of minor planet at event [mag]: 12.3
 * geocentric parallax of minor planet ["]: 3.670
 * magnitude drop [mag]: 5.0
 * estimated maximum duration [s]: 8.3
 * apparent motion of minor planet ["/h]: 48.97
 * angular distance to moon, phase of moon [deg,%]: 154, 50%
 * remarks: 

Calculator(s): Jan Manek





Path coordinates:
                                       Altitude
  E. Longitude    Latitude     U.T.    star  sun
   ........ shortened ..........................
      o  '  "     o  '  "    h  m  s     o     o
   - 10 13 44    24  0  0    3 23 45    54   -34
   -  9 46 35    25  0  0    3 23 49    54   -33
   -  9 19 35    26  0  0    3 23 54    55   -32
   -  8 52 42    27  0  0    3 23 59    56   -31
   -  8 25 57    28  0  0    3 24  3    57   -30
   -  7 59 16    29  0  0    3 24  8    58   -29
   -  7 32 41    30  0  0    3 24 13    58   -29
   -  7  6  8    31  0  0    3 24 17    59   -28
   -  6 39 38    32  0  0    3 24 22    60   -27
   -  6 13  8    33  0  0    3 24 27    61   -26
   -  5 46 39    34  0  0    3 24 32    61   -25
   -  5 20  7    35  0  0    3 24 36    62   -24
   -  4 53 33    36  0  0    3 24 41    62   -23
   -  4 26 55    37  0  0    3 24 46    63   -22
   -  4  0 11    38  0  0    3 24 51    64   -21
   -  3 33 20    39  0  0    3 24 56    64   -20
   -  3  6 21    40  0  0    3 25  1    64   -19
   -  2 39 11    41  0  0    3 25  6    65   -18
   -  2 11 49    42  0  0    3 25 11    65   -17
   -  1 44 14    43  0  0    3 25 16    66   -16
   -  1 16 23    44  0  0    3 25 21    66   -15
   -  0 48 14    45  0  0    3 25 26    66   -14
   -  0 19 44    46  0  0    3 25 31    66   -13
      0  9  7    47  0  0    3 25 35    66   -12
      0 38 24    48  0  0    3 25 40    66   -12
      1  8  8    49  0  0    3 25 45    66   -11
      1 38 23    50  0  0    3 25 50    66   -10
      2  9 13    51  0  0    3 25 55    66    -9
      2 40 40    52  0  0    3 26  0    66    -8
      3 12 49    53  0  0    3 26  5    66    -7
      3 45 45    54  0  0    3 26 10    66    -6
      4 19 31    55  0  0    3 26 15    65    -5
      4 54 14    56  0  0    3 26 20    65    -4
   ........ 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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