Update for (54) Alexandra - February 12/13, 2003

Jan Manek's update

                 IOTA/IOTA-ES occultation update for
        (54) Alexandra / TYC 2411-00003-1 on February 12/13, 2003
                  visible from sunlit part of Earth

Summary 

In the night of February 12/13, 2003 a faint 10.1 mag star TYC 2411-00003-1 will be occulted by a 171 km asteroid (54) Alexandra. 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 west shift with time 0.2 minutes earlier compared to Edwin Goffin's nominal prediction.

Updated path runs over solely over sunlit part of Earth, confirming the Goffin's nominal prediction. Unobservable event. Please check the path chart for details.

The event at one glimpse:
 * Goffin's original chart reference: A03_0229

Data for the target star:
 * name: TYC 2411-00003-1
 * constellation: Auriga
 * J2000 position [h,m,s; o,',"]: 05h 33m 00.4765s; +31o 32' 31.784"
 * position source: recent UCAC position combined with Tycho-2 proper motion
 * estimated accuracy ["]: 0.02" (0.01", 0.01")
 * V mag [mag]: 10.13
 * B-V [mag]: +0.20
 * remarks:
    !!! 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.

Data for the minor planet:
 * general information:
     number, name: (54) Alexandra
     approx. diameter [km]: 171
 * orbital information
     orbit source: calculation Manek
     source of used astrometry: USNO/Flagstaff (Ron Stone)
     number of used observations: 105 USNO, 10 TMO
     number of rejected observations: 8 USNO, 2 TMO
     time covered by the observations: 1998 11 14 - 2003 01 17
     rms residuals ["] (RA,DE): 0.06", 0.06"
     estimated positional accuracy at epoch of event ["]: 0.03", 0.03"
     remarks:

Data for the event:
 * UT date and time of least geocentric approach: 18:09.7 UT
 * approx. V mag of minor planet at event [mag]: 13.1
 * geocentric parallax of minor planet ["]: 3.395
 * magnitude drop [mag]: 3.1
 * estimated maximum duration [s]: 29.5
 * apparent motion of minor planet ["/h]: 11.10
 * angular distance to moon, phase of moon [deg,%]: 9, 80%
 * remarks:

Elements for WinOccult:
============ cut here ===========================================
 2003 Feb 12
54 Alexandra
18h  9.7m UT
04-00431-1  10.1    5 33  0.477 31 32 31.78TYC 2404-00431-1
13.1    171   29.5   2.590    -0.105    -11.02
   28.456  31.545   271.15  -13.65
 18.1611  -.59778   .07306 -0.40031 -3.24499  0.00518 -0.00019
2000    151.1358082003 210.00000345.046755313.52827311.828850 0.198404002.710758842.172933457.665   0.15
RATE 2.2083490 .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  '  "
                                                   Latitude   Latitude
   - 96  0  0    50 34 59   17 55  6     4    25   49 14 12   51 53 59
   - 93  0  0    52 19 20   17 55 12     6    24   51  3 49   53 33 22
   - 90  0  0    53 46 11   17 55 19     9    23   52 34 50   54 56 17
   - 87  0  0    54 58 40   17 55 28    11    21   53 50 37   56  5 35
   - 84  0  0    55 59  1   17 55 38    13    20   54 53 39   57  3 24
   - 81  0  0    56 48 57   17 55 49    15    20   55 45 43   57 51 17
   - 78  0  0    57 29 44   17 56  1    16    19   56 28 11   58 30 25
   - 75  0  0    58  2 18   17 56 13    18    18   57  2  5   59  1 43
   - 72  0  0    58 27 23   17 56 26    20    17   57 28  9   59 25 51
   - 69  0  0    58 45 29   17 56 40    21    16   57 46 56   59 43 17
   - 66  0  0    58 56 58   17 56 54    23    16   57 58 50   59 54 23
   - 63  0  0    59  2  3   17 57 10    24    15   58  4  2   59 59 19
   - 60  0  0    59  0 48   17 57 26    26    14   58  2 39   59 58 12
   - 57  0  0    58 53 10   17 57 43    27    14   57 54 36   59 50 58
   - 54  0  0    58 38 59   17 58  1    29    13   57 39 42   59 37 28
   - 51  0  0    58 17 55   17 58 21    30    13   57 17 36   59 17 22
   - 48  0  0    57 49 27   17 58 42    32    12   56 47 45   58 50 14
   - 45  0  0    57 12 55   17 59  5    33    11   56  9 25   58 15 23
   - 42  0  0    56 27 19   17 59 30    35    11   55 21 32   57 31 58
   - 39  0  0    55 31 23   17 59 58    37    10   54 22 41   56 38 46
   - 36  0  0    54 23 17   18  0 29    38    10   53 10 54   55 34  8
   - 33  0  0    53  0 34   18  1  5    40     9   51 43 25   54 15 49
   - 30  0  0    51 19 37   18  1 45    42     9   49 56 14   52 40 38
   - 27  0  0    49 15  8   18  2 33    44     8   47 43 13   50 43 52
   - 24  0  0    46 38 31   18  3 31    46     7   44 54 19   48 18  9
                                                  Longitude  Longitude
   - 20  5 45    42  0  0   18  5 11    49     7 - 21 34 60 - 18 38 49
   - 18 15  6    39  0  0   18  6 14    51     7 - 19 37 15 - 16 54 47
   - 16 47 49    36  0  0   18  7 15    52     6 - 18  4 28 - 15 32 39
   - 15 39 14    33  0  0   18  8 17    53     6 - 16 51 33 - 14 28 11
   - 14 46  3    30  0  0   18  9 17    53     7 - 15 54 52 - 13 38 19
   - 14  5 50    27  0  0   18 10 16    53     7 - 15 11 51 - 13  0 48
   - 13 36 48    24  0  0   18 11 15    52     7 - 14 40 31 - 12 33 58
   - 13 17 34    21  0  0   18 12 12    52     8 - 14 19 26 - 12 16 31
   - 13  7  6    18  0  0   18 13  9    51     8 - 14  7 29 - 12  7 28
   - 13  4 36    15  0  0   18 14  4    50     9 - 14  3 50 - 12  6  5
   - 13  9 30    12  0  0   18 14 59    48     9 - 14  7 53 - 12 11 49
   - 13 21 23     9  0  0   18 15 51    46    10 - 14 19 10 - 12 24 16
   - 13 39 59     6  0  0   18 16 42    44    11 - 14 37 27 - 12 43 12
   - 14  5 12     3  0  0   18 17 32    42    12 - 15  2 35 - 13  8 30
   - 14 37  1     0  0  0   18 18 19    40    13 - 15 34 34 - 13 40 10
   - 15 15 35   - 3  0  0   18 19  5    38    14 - 16 13 33 - 14 18 21
   - 16  1 11   - 6  0  0   18 19 48    35    16 - 16 59 50 - 15  3 16
   - 16 54 13   - 9  0  0   18 20 29    33    17 - 17 53 52 - 15 55 23
   - 17 55 21   -12  0  0   18 21  8    30    18 - 18 56 19 - 16 55 14
   - 19  5 22   -15  0  0   18 21 44    27    20 - 20  8  3 - 18  3 39
   - 20 25 26   -18  0  0   18 22 16    24    21 - 21 30 17 - 19 21 39
   - 21 57  1   -21  0  0   18 22 46    21    23 - 23  4 36 - 20 50 39
   - 23 42  7   -24  0  0   18 23 13    18    25 - 24 53 11 - 22 32 29
   - 25 43 29   -27  0  0   18 23 35    14    27 - 26 58 59 - 24 29 42
   - 28  4 55   -30  0  0   18 23 54    11    29 - 29 26 14 - 26 45 46
   - 30 52  2   -33  0  0   18 24  7     7    31 - 32 21 14 - 29 25 43
   ........................... 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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