Update for (82) Alkmene - April 4/5, 2003

Jan Manek's update

                    IOTA/IOTA-ES occultation update for
             (82) Alkmene / TYC 1899-01174-1 on April 4/5, 2003
     visible from Portugal, S Spain, Algeria, S Tunisia, Libya and S Egypt

Summary 

In the evening of April 4/5, 2003 a faint 10.8 mag star TYC 1899-01174-1 will be occulted by a 64 km asteroid (82) Alkmene. This update is based on USNO/Flagstaff and TMO astrometry for the asteroid and recent UCAC star position.

The updated path shows ~1 path width NE shift with time 0.8 minutes earlier compared to Edwin Goffin's nominal prediction.

Updated path runs over Portugal just north of Lisbon ~20:29.9 UT, S Spain around 20:30.2 UT, Algeria ~20:30.6 UT, S Tunisia ~20:31.3 UT, Libya ~20:31.9 UT and S Egypt ~20:32.5 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: April 4, 2003 @ 20:30 UT (Europe)
 * magnitude of target star: 10.8
 * magnitude drop [mag]: 1.9
 * estimated maximum duration [s]: 3.3
 * path description: given above
 * Goffin's original chart reference: A03_0416

The occultation path:
 * approximate ground width [km]: 70
 * uncertainty [path widths]: 1.0
 * uncertainty in time [s]: 3
 * 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 1899-01174-1
 * constellation: Gemini
 * J2000 position [h,m,s; o,',"]: 07h 03m 34.4440s; +25o 43' 00.137"
 * position source: recent UCAC position combined with Tycho-2 proper motion
 * estimated accuracy ["]: 0.03" (0.01", 0.02")
 * V mag [mag]: 10.81
 * B-V [mag]: +0.64
 * remarks:
    Target star is in middle Gemini, about 4.5 degrees east of 3.0 mag star epsilon Geminorum = SAO 78682.
    !!! 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 12.5
 * labeled stars have indicated SAO numbers
 * remarks: Second chart is 30' blowup to show correctly the target star in the field.











Data for the minor planet:
 * general information:
     number, name: (82) Alkmene
     approx. diameter [km]: 64
 * orbital information
     orbit source: calculation Manek
     source of used astrometry: USNO/Flagstaff (Ron Stone), TMO (Bill Owen)
     number of used observations: 121 USNO, 9 TMO
     number of rejected observations: 8 USNO
     time covered by the observations: 1999 01 01 - 2003 03 22
     rms residuals ["] (RA,DE): 0.07", 0.07"
     estimated positional accuracy at epoch of event ["]: 0.03", 0.04"
     remarks:

Data for the event:
 * UT date and time of least geocentric approach: 20:28.3 UT
 * approx. V mag of minor planet at event [mag]: 12.5
 * geocentric parallax of minor planet ["]: 4.641
 * magnitude drop [mag]: 1.9
 * estimated maximum duration [s]: 3.3
 * apparent motion of minor planet ["/h]: 51.07
 * angular distance to moon, phase of moon [deg,%]: 57, 8%
 * remarks:

Elements for WinOccult:
============ cut here ===========================================
 2003 Apr 04
82 Alkmene
20h 28.3m UT
99-01174-1  10.8    7  3 34.444 25 43  0.14TYC 1899-01174-1
12.5     64    3.3   1.895     3.720     -9.06
  -33.930  25.720  -126.32    5.78
 20.4720   .05484   .31194 10.83551 -1.95281  0.00540 -0.00059
2000    356.7481202003 4 1.00000110.50218525.640476 2.833221  0.225431192.759817242.137668368.405   0.28
RATE 2.1497280 .0000000 .0000000 .0000000 .00000000 .00000000 .00000000
============ cut here ===========================================

Calculator(s): Jan Manek








Path coordinates:
                  Centre               Altitude       Path Limits
  E. Longitude   Latitude      U.T.   star   sun   Limit 1    Limit 2
                                                   Latitude   Latitude
  ............................. shortened ..................................
      o  '  "     o  '  "    h  m  s     o     o    o  '  "    o  '  "
   - 13  0  0    40 23 15   20 29 33    67   -14   40  3 49   40 42 42
   - 12  0  0    40  6 16   20 29 37    66   -15   39 46 48   40 25 47
   - 11  0  0    39 48 52   20 29 42    66   -16   39 29 21   40  8 26
   - 10  0  0    39 31  3   20 29 46    65   -16   39 11 29   39 50 40
   -  9  0  0    39 12 48   20 29 51    65   -17   38 53 11   39 32 28
   -  8  0  0    38 54  8   20 29 56    64   -18   38 34 28   39 13 51
   -  7  0  0    38 35  2   20 30  0    64   -19   38 15 19   38 54 48
   -  6  0  0    38 15 31   20 30  5    63   -20   37 55 45   38 35 20
   -  5  0  0    37 55 35   20 30 10    62   -21   37 35 45   38 15 27
   -  4  0  0    37 35 13   20 30 14    62   -22   37 15 20   37 55  8
   -  3  0  0    37 14 26   20 30 19    61   -22   36 54 30   37 34 24
   -  2  0  0    36 53 13   20 30 24    60   -23   36 33 14   37 13 15
   -  1  0  0    36 31 36   20 30 28    60   -24   36 11 34   36 51 40
      0  0  0    36  9 33   20 30 33    59   -25   35 49 28   36 29 41
      1  0  0    35 47  6   20 30 38    58   -26   35 26 58   36  7 16
      2  0  0    35 24 14   20 30 42    57   -27   35  4  3   35 44 27
      3  0  0    35  0 57   20 30 47    56   -28   34 40 43   35 21 14
      4  0  0    34 37 16   20 30 51    56   -29   34 16 60   34 57 36
      5  0  0    34 13 11   20 30 56    55   -30   33 52 52   34 33 34
      6  0  0    33 48 43   20 31  1    54   -31   33 28 20   34  9  8
      7  0  0    33 23 50   20 31  5    53   -32   33  3 25   33 44 18
      8  0  0    32 58 35   20 31 10    52   -32   32 38  7   33 19  5
      9  0  0    32 32 56   20 31 14    51   -33   32 12 26   32 53 30
     10  0  0    32  6 55   20 31 19    51   -34   31 46 22   32 27 31
     11  0  0    31 40 32   20 31 23    50   -35   31 19 57   32  1 11
     12  0  0    31 13 47   20 31 28    49   -36   30 53 10   31 34 28
     13  0  0    30 46 41   20 31 32    48   -37   30 26  1   31  7 24
     14  0  0    30 19 15   20 31 37    47   -38   29 58 32   30 39 60
     15  0  0    29 51 27   20 31 41    46   -39   29 30 43   30 12 15
     16  0  0    29 23 21   20 31 45    45   -40   29  2 34   29 44 10
     17  0  0    28 54 55   20 31 50    44   -41   28 34  6   29 15 46
     18  0  0    28 26 10   20 31 54    43   -42   28  5 20   28 47  3
     19  0  0    27 57  8   20 31 58    42   -43   27 36 15   28 18  3
     20  0  0    27 27 48   20 32  2    41   -44   27  6 54   27 48 45
     21  0  0    26 58 11   20 32  6    40   -45   26 37 16   27 19 10
     22  0  0    26 28 19   20 32 10    39   -46   26  7 22   26 49 19
     23  0  0    25 58 12   20 32 14    38   -47   25 37 14   26 19 13
     24  0  0    25 27 50   20 32 18    37   -48   25  6 51   25 48 52
     25  0  0    24 57 14   20 32 22    36   -49   24 36 14   25 18 18
     26  0  0    24 26 26   20 32 25    35   -50   24  5 25   24 47 30
     27  0  0    23 55 26   20 32 29    34   -51   23 34 24   24 16 31
     28  0  0    23 24 15   20 32 33    33   -52   23  3 12   23 45 20
     29  0  0    22 52 53   20 32 36    32   -53   22 31 50   23 13 59
     30  0  0    22 21 22   20 32 40    31   -54   22  0 19   22 42 29
     31  0  0    21 49 43   20 32 43    30   -55   21 28 39   22 10 50
     32  0  0    21 17 56   20 32 46    29   -56   20 56 53   21 39  3
     33  0  0    20 46  3   20 32 49    28   -57   20 24 59   21  7 10
     34  0  0    20 14  4   20 32 52    27   -58   19 53  1   20 35 11
     35  0  0    19 42  1   20 32 55    26   -59   19 20 58   20  3  7
     36  0  0    19  9 54   20 32 58    25   -60   18 48 51   19 31  0
     37  0  0    18 37 44   20 33  1    24   -61   18 16 42   18 58 50
     38  0  0    18  5 33   20 33  3    23   -62   17 44 31   18 26 38
     39  0  0    17 33 21   20 33  6    21   -63   17 12 20   17 54 25
     40  0  0    17  1 10   20 33  8    20   -64   16 40 10   17 22 13
     41  0  0    16 28 59   20 33 10    19   -65   16  8  0   16 50  1
     42  0  0    15 56 51   20 33 12    18   -66   15 35 54   16 17 52
     43  0  0    15 24 47   20 33 14    17   -67   15  3 50   15 45 46
     44  0  0    14 52 46   20 33 16    16   -68   14 31 51   15 13 44
     45  0  0    14 20 51   20 33 18    15   -69   13 59 58   14 41 47
     46  0  0    13 49  2   20 33 20    14   -69   13 28 10   14  9 57
     47  0  0    13 17 20   20 33 21    13   -70   12 56 30   13 38 13
     48  0  0    12 45 47   20 33 23    12   -71   12 24 58   13  6 38
     49  0  0    12 14 22   20 33 24    10   -72   11 53 36   12 35 11
     50  0  0    11 43  7   20 33 25     9   -72   11 22 23   12  3 55
     51  0  0    11 12  3   20 33 26     8   -73   10 51 21   11 32 49
  ............................. 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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