Update for (80) Sappho - July 1/2, 2000

Jan Manek's update

                    IOTA/IOTA-ES occultation update for
   (80) Sappho / TYC 5156-02199-1 = PPM 203099 event on July 1/2, 2000
      visible from N Burma, Nepal, NE and NW India, middle Pakistan,
           S Afghanistan, middle Iran, N Iraq, NE Syria, Turkey,
   N Greece, S of frm.Yugoslavia, N Albania, N Italy and middle France


Summary 

In the night of July 1/2, 2000 a 10.1 mag star TYC 5156-02199-1 = PPM 203099 will be occulted by a 82 km asteroid (80) Sappho. This update is based on USNO/Flagstaff and TMO astrometry for the asteroid and Tycho-2 star position.

The updated path shows ~1.5 path width north shift with time ~0.4 minutes earlier compared to Edwin Goffin's nominal prediction.

The path of this occultation runs over N Burma in twiligh ~22:06.5 UT, Nepal ~22:08 UT, NE and NW India ~22:07 UT and 22:10 UT respectively, middle Pakistan ~22:11.5 UT, S Afghanistan ~22:13 UT, middle Iran ~22:15 UT, N Iraq ~22:17 UT, NE Syria ~22:18 UT, Turkey ~22:19-22:20 UT. Finally the path runs over European continent ans starts at N Greece ~22:21 UT and runs over S of frm.Yugoslavia and N Albania ~22:22 UT, N Italy ~22:23 UT and middle France ~22:24 UT. Please consult the chart for details.

Keep in mind that the brightness drop will be only ~0.9 magnitudes, so video observations, IOC recording or time calibrated CCD scans are preferred to get good timing accuracy.

The event at one glimpse:
 * date and approx. UT time of event: July 1, 2000 @ 22:10 UT (India)
                                                     22:23 UT (Europe)
 * magnitude of target star: 10.1
 * magnitude drop [mag]: 0.9
 * estimated maximum duration [s]: 11.4
 * path description: given above
 * Goffin's original chart reference: A00_0707

The occultation path:
 * approximate ground width [km]: 110
 * uncertainty [path widths]: 0.9
 * 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: PPM 203099 = TYC 5156-02199-1
 * constellation: Aquila
 * J2000 position [h,m,s; o,',"]: 19h 37m 29.395s; -05o 45' 50.56"
 * position source: Tycho-2
 * estimated accuracy ["]: 0.05 (0.03", 0.04")
 * V mag [mag]: 10.06
 * B-V [mag]: +0.90
 * remarks: 
     Target star is in southern Aquila, ~8 degrees east of 3.4 mag star 
     lambda Aquilae. The star is almost midway between 5.0 mag star kappa 
     Aquilae and 5.5 mag star 42 Aquilae. There is 9.5 mag star SAO 143617 
     only 4' ESE which may be use as reference star for this low amplitude 
     event.

Close finding chart (prepared in GUIDE7):
 * occulted star is in center - labeled with cross
 * field is 2.5x2.5 degrees
 * limiting magnitude is 12.5
 * labeled stars have indicated SAO numbers





Data for the minor planet:
 * general information:
     number, name: (80) Sappho
     approx. diameter [km]: 82
 * orbital information
     orbit source: calculation Manek
     source of used astrometry: USNO/Flagstaff (Ron Stone), TMO (Bill Owen)
     number of used observations: 32 USNO, 3 TMO
     number of rejected observations: 3 USNO
     time covered by the observations: 1998 01 29 - 2000 06 25
     rms residuals ["] (RA,DE): 0.06", 0.06"
     estimated positional accuracy at epoch of event ["]: 0.05"
     remarks: excellent set of observations

Data for the event:
 * UT date and time of least geocentric approach: 22:15.4  UT
 * approx. V mag of minor planet at event [mag]: 10.4
 * geocentric parallax of minor planet ["]: 8.120
 * magnitude drop [mag]: 0.9
 * estimated maximum duration [s]: 11.4
 * apparent motion of minor planet ["/h]: 33.05
 * angular distance to moon, phase of moon [deg,%]: 161, 0%
 * remarks: 

Calculator(s): Jan Manek








Path coordinates:
                                       Altitude
  E. Longitude    Latitude     U.T.    star  sun
      o  '  "     o  '  "    h  m  s     o     o
   ........ shortened ..........................
    100  0  0    26 16 21   22  6 20    26    -6
     98  0  0    26 23 44   22  6 36    27    -7
     96  0  0    26 32 16   22  6 53    29    -9
     94  0  0    26 41 59   22  7 10    30   -10
     92  0  0    26 52 51   22  7 29    32   -11
     90  0  0    27  4 51   22  7 48    33   -13
     88  0  0    27 17 57   22  8  7    35   -14
     86  0  0    27 32  8   22  8 28    36   -15
     84  0  0    27 47 23   22  8 49    37   -16
     82  0  0    28  3 41   22  9 10    39   -18
     80  0  0    28 20 60   22  9 32    40   -19
     78  0  0    28 39 18   22  9 55    41   -20
     76  0  0    28 58 35   22 10 18    42   -21
     74  0  0    29 18 48   22 10 42    43   -22
     72  0  0    29 39 56   22 11  5    44   -23
     70  0  0    30  1 57   22 11 30    45   -24
     68  0  0    30 24 49   22 11 54    46   -24
     66  0  0    30 48 30   22 12 19    46   -25
     64  0  0    31 12 58   22 12 44    47   -26
     62  0  0    31 38 11   22 13  9    48   -26
     60  0  0    32  4  8   22 13 34    48   -27
     58  0  0    32 30 46   22 13 60    48   -27
     56  0  0    32 58  2   22 14 25    49   -28
     54  0  0    33 25 55   22 14 51    49   -28
     52  0  0    33 54 22   22 15 16    49   -28
     50  0  0    34 23 21   22 15 41    49   -29
     48  0  0    34 52 49   22 16  7    49   -29
     46  0  0    35 22 45   22 16 32    49   -29
     44  0  0    35 53  4   22 16 56    48   -29
     42  0  0    36 23 46   22 17 21    48   -29
     40  0  0    36 54 47   22 17 45    47   -29
     38  0  0    37 26  4   22 18 10    47   -29
     36  0  0    37 57 36   22 18 33    46   -28
     34  0  0    38 29 19   22 18 57    46   -28
     32  0  0    39  1 10   22 19 20    45   -28
     30  0  0    39 33  8   22 19 42    44   -27
     28  0  0    40  5  9   22 20  4    43   -27
     26  0  0    40 37 10   22 20 26    42   -26
     24  0  0    41  9 10   22 20 47    41   -26
     22  0  0    41 41  5   22 21  7    40   -25
     20  0  0    42 12 54   22 21 27    39   -25
     18  0  0    42 44 32   22 21 46    38   -24
     16  0  0    43 15 58   22 22  5    37   -23
     14  0  0    43 47 10   22 22 23    36   -23
     12  0  0    44 18  5   22 22 41    35   -22
     10  0  0    44 48 40   22 22 57    33   -21
      8  0  0    45 18 54   22 23 14    32   -20
      6  0  0    45 48 45   22 23 29    31   -19
      4  0  0    46 18  9   22 23 44    30   -18
      2  0  0    46 47  6   22 23 58    29   -17
      0  0  0    47 15 33   22 24 12    27   -16
   -  2  0  0    47 43 29   22 24 25    26   -15
   -  4  0  0    48 10 52   22 24 37    25   -14
   -  6  0  0    48 37 40   22 24 48    24   -13
   -  8  0  0    49  3 51   22 24 59    22   -12
   - 10  0  0    49 29 25   22 25  9    21   -11
   - 12  0  0    49 54 21   22 25 19    20   -10
   - 14  0  0    50 18 36   22 25 28    19    -9
   - 16  0  0    50 42  9   22 25 36    17    -8
   - 18  0  0    51  5  1   22 25 44    16    -7
   ........ 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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