The occultation of 8.1-mag. SAO 162175 by 1243 Pamela on Tuesday morning, April 28, will occur 7.4 path widths east of that shown on p. 86 of the February issue of Sky and Telescope (also on www.skypub.com's occultation page), passing over populous parts near the east coast of the USA, as well as eastern Mexico or Guatemala. The time will be 1.4 minutes earlier than indicated on the map. This puts the path over the central Florida peninsula at 8:51 UT (4:51 am EDT), over eastern Georgia and S. Car. (Savannah, Charleston) at 8:52 UT, over central N. Carolina, over the Dulles airport area at 8:53 UT (that is, just west of Washington, DC, with the city possibly within the path), over central Pennsylvania and New York, and west of Montreal at 8:54 UT. The asteroid is small, subtending only about 0.04", so the prediction could be in error by 3 path widths; the time should be good to within a minute or so. Please spread the word about this event to others in your area by telephone. Note that this prediction, based on 7 CCD exposures by Gordon Garradd at Loomberah, Australia, is consistent, within the error bars, of Pedro Valdez Sada's prediction from April 1 & 21 observations at Monterrey, Mexico, using less accurate Tycho data (that path being farther east). The position of the star has not been updated, but it is too bright relative to the asteroid to get a good position with new ground-based observations. The position of the star from the ACT catalog, used for the prediction, should be more accurate than the updated ephemeris of Pamela based on the new observations.
The star is at J2000 RA 19h 5m 38.5s, Dec -16 deg. 33' 40". Finder charts and general information for this good occultation by Pamela are on pp. 94-95 of the April issue of Sky and Telescope, and on the skypub.com Web site occultation page; they also give general information about these events. More detailed charts from the IOTA Occ'n Newsletter North American Asteroidal Occultation Supplement for 1998 for the occultation is (or soon will be) on IOTA's Web sites at http://www.sky.net/~robinson/iotandx.htm and/or at http://www.anomalies.com/iota/splash.htm, there in the table of North American events at the top of the "upcoming events" section.
Details of the new prediction are below.
David Dunham, IOTA, 1998 April 27
OCCULTATION OF 8.14-MAG. SAO 162175 (PPM 235475, SPECTRAL TYPE K0)
BY 1243 Pamela ON 1998 APR 28
IN VISUAL, DROP AT DISAPPEARANCE= 6.85 EPHEMERIS SOURCE = Garradd
DIAMETER= 76. KM = 0.042 SECONDS OF ARC, CENTRAL OCCN. = 9.187 SECONDS
DIAMETER OF STAR= 0.602 ARC MILLISECONDS= 1086.0 METERS= 3.491
FRINGES
CENTRAL TIME TO COVER STAR= 0.1313 SECONDS
CENTER PATH IS ABOUT 99. KM WIDE AT THE COORDINATES LISTED BELOW
UNIV. TIME Pamela SUN MOON
LONGITUDE LATITUDE H M S ALT. AZI. ALT. AZI. ALT.
95.56 W 5.01 8 45 29.2 49.7 123.1 -49.1 61.6 -67.3
94.62 W 6.15 8 45 49.7 49.9 125.0 -47.7 61.1 -65.8
93.70 W 7.31 8 46 10.3 50.0 126.9 -46.2 60.7 -64.4
92.80 W 8.48 8 46 30.9 50.1 128.8 -44.8 60.2 -62.9
91.92 W 9.68 8 46 51.4 50.0 130.8 -43.4 59.8 -61.4
91.07 W 10.90 8 47 12.0 49.9 132.8 -42.0 59.5 -59.9
90.23 W 12.13 8 47 32.5 49.7 134.8 -40.6 59.1 -58.4
89.41 W 13.38 8 47 52.9 49.4 136.8 -39.2 58.8 -56.9
88.61 W 14.65 8 48 13.2 49.1 138.7 -37.8 58.5 -55.3
87.83 W 15.93 8 48 33.4 48.6 140.6 -36.4 58.3 -53.8
87.07 W 17.23 8 48 53.5 48.1 142.5 -35.0 58.0 -52.3
86.33 W 18.54 8 49 13.4 47.5 144.3 -33.7 57.8 -50.8
85.61 W 19.87 8 49 33.1 46.9 146.0 -32.3 57.6 -49.2
84.90 W 21.21 8 49 52.5 46.2 147.7 -31.0 57.4 -47.7
84.21 W 22.56 8 50 11.7 45.4 149.4 -29.6 57.3 -46.2
83.54 W 23.93 8 50 30.7 44.5 150.9 -28.3 57.1 -44.6
82.88 W 25.30 8 50 49.3 43.6 152.5 -27.0 57.0 -43.1
82.24 W 26.69 8 51 7.7 42.7 153.9 -25.7 56.9 -41.6
81.62 W 28.09 8 51 25.7 41.7 155.3 -24.4 56.9 -40.1
81.01 W 29.50 8 51 43.3 40.7 156.6 -23.2 56.8 -38.6
80.42 W 30.92 8 52 0.6 39.6 157.8 -21.9 56.8 -37.0
79.84 W 32.35 8 52 17.4 38.4 159.0 -20.7 56.8 -35.5
79.28 W 33.79 8 52 33.9 37.3 160.1 -19.4 56.8 -34.0
78.74 W 35.23 8 52 49.9 36.1 161.2 -18.2 56.8 -32.5
78.22 W 36.69 8 53 5.4 34.9 162.2 -17.0 56.9 -31.1
77.71 W 38.15 8 53 20.4 33.6 163.1 -15.8 56.9 -29.6
77.21 W 39.62 8 53 35.0 32.3 164.0 -14.7 57.0 -28.1
76.74 W 41.10 8 53 49.0 31.0 164.8 -13.5 57.1 -26.6
76.28 W 42.58 8 54 2.5 29.7 165.6 -12.4 57.2 -25.2
75.84 W 44.07 8 54 15.5 28.3 166.3 -11.3 57.3 -23.7
75.42 W 45.57 8 54 27.9 26.9 167.0 -10.2 57.4 -22.3
75.03 W 47.07 8 54 39.7 25.5 167.6 -9.1 57.6 -20.8
74.65 W 48.57 8 54 50.9 24.1 168.2 -8.1 57.7 -19.4
74.30 W 50.09 8 55 1.5 22.7 168.8 -7.1 57.9 -18.0
73.98 W 51.60 8 55 11.5 21.2 169.3 -6.1 58.0 -16.6
73.69 W 53.12 8 55 20.8 19.8 169.7 -5.1 58.1 -15.2
73.42 W 54.65 8 55 29.5 18.3 170.1 -4.1 58.3 -13.8
73.20 W 56.17 8 55 37.5 16.8 170.4 -3.2 58.4 -12.5
CENTER FOR 1243 Pamela SAO 162175 DATE 1998 APR 28
W. LONG. LAT. W. LONG. LAT. W. LONG. LAT. W. LONG.
LAT.
83.025 25 0.0 79.588 33 0.0 76.768 41 0.0 74.553 49
0.0
82.558 26 0.0 79.203 34 0.0 76.457 42 0.0 74.323 50
0.0
82.103 27 0.0 78.828 35 0.0 76.155 43 0.0 74.106 51
0.0
81.658 28 0.0 78.462 36 0.0 75.863 44 0.0 73.901 52
0.0
81.224 29 0.0 78.105 37 0.0 75.580 45 0.0 73.709 53
0.0
80.800 30 0.0 77.757 38 0.0 75.308 46 0.0 73.530 54
0.0
80.386 31 0.0 77.418 39 0.0 75.046 47 0.0 73.367 55
0.0
79.982 32 0.0 77.088 40 0.0 74.794 48 0.0 73.220 56
0.0
AT U.T. 8 50 0, W. LONG.= 84.631, LAT.= 21.733
AT U.T. 8 51 0, W. LONG.= 82.508, LAT.= 26.108
AT U.T. 8 52 0, W. LONG.= 80.439, LAT.= 30.872
AT U.T. 8 53 0, W. LONG.= 78.398, LAT.= 36.176
AT U.T. 8 54 0, W. LONG.= 76.366, LAT.= 42.296
AT U.T. 8 55 0, W. LONG.= 74.353, LAT.= 49.869
MIN. GEOCENTRIC Shifts from nominal Prediction comparison
U. T. SEP. Time Path
h m " m " widths
8 47.9 2.58W 0.0 0.00 0.0 Nominal, p. 86 of 1998 Feb. S&T
8 46.5 2.27W -1.4 0.21E 7.4E Garradd update, 7 ACT images, Apr. 26