The path of the occultation of TAC S05 2851 by 105 Artemis the night of February 11-12 (12th UT) will cross the U.S.A. from the Ozona - Snyder area of Texas shortly after 5:31 UT to the Winnipeg, Manitoba area at 5:34 UT, 2.4 path widths west of the path shown on my map on p. 86 of this month's issue of Sky and Telescope (and also given at SkyPub's Web site at http://www.skypub.com/occults/occults.htm), and the time will be 0.6 minute later than indicated there, according to 7 HIP and ACT- relative observations made 1998 Jan. 24 - Feb. 2 at USNO-Flagstaff. This is 0.8 path width east of my prediction issued on Feb. 6, when I noted that the path would be farther east if only the late Jan. observations were used. Since the new Feb. 2nd observation confirms that, I believe just using the later observations is best. Also, the star was observed in the same CCD field on Feb. 2nd, and the location of the path using only that data, where the relative accuracy may be a little better, agrees well with the new path using all of the last 7 observations. I believe that the new path is accurate to about +/-1 path-width, and probably is better than that.

The star is located at J2000 RA 6h 06m 23.2s, Dec -05 deg. 27' 30" about 8 deg. east of the sword of Orion (Orion Nebula) and 2 deg. west and 0.7 deg. north of gamma Monocerotis. A finder chart is on p. 89 of the Feb. issue of Sky and Tel., as well as on the skypub Web site, with a more detailed one in the 1998 Asteroidal Occultation Supplement for North America that was distributed a month ago to IOTA Occultation Newsletter subscribers.

The version posted on the IOTA Web sites also shows the "Feb. 6th" path passing over central Uruguay, and Rafaela and Santa Fe, Argentina, at 5:19 UT; 1 deg. of lat. north of Cordoba Obs. at Bosque Alegre, Argentina; 2 deg. of lat. north of the European Southern Observatory in Chile at 5:20 UT; 2 deg. of long. west of Mexico City at 5:29 UT; and near Saltillo, Mexico, at 5:30; but note that the new path is 0.8 path-widths (or about 1 deg. of latitude) north of that path in South America, and a similar amount east of it in Mexico (so the path is more likely to pass over Mexico City and/or Monterrey).

Latest and best map

 OCCULTATION OF  9.99-MAG. TAC S05 deg. 2851, SPECTRAL TYPE maybe G) 
 BY 105 Artemis ON 1998 FEB 12, IN VISUAL, MAG. DROP AT DISAPPEARANCE= 2.66
 DIAMETER= 123. KM = 0.087 SECONDS OF ARC, CENTRAL OCCN. = 12.022 SECONDS
 99-PERCENT-SUNLIT WANING MOON  64.1 DEGREES AWAY, SUN  123.01 DEGREES AWAY
 Artemis 1.956520 A.U. FROM EARTH, PHASE ANGLE=  18.3DEGREES

 CENTER PATH IS ABOUT   156. KM WIDE AT THE COORDINATES LISTED BELOW

                      UNIV. TIME  Artemis         SUN       MOON
  LONGITUDE  LATITUDE  H  M   S   ALT.  AZI.   ALT.  AZI.   ALT.

    46.08 W   -33.76   5 19  4.5   7.9 268.7  -34.5 143.7   41.4
    47.98 W   -33.59   5 19  7.7   9.4 269.7  -35.5 145.6   42.3
    49.87 W   -33.36   5 19 11.6  11.0 270.7  -36.6 147.5   43.2
    51.75 W   -33.08   5 19 16.0  12.6 271.6  -37.6 149.4   44.1
    53.61 W   -32.73   5 19 21.0  14.1 272.6  -38.7 151.3   45.0
    55.44 W   -32.32   5 19 26.6  15.7 273.5  -39.8 153.3   45.9
    57.25 W   -31.86   5 19 32.8  17.2 274.3  -40.9 155.2   46.7
    59.03 W   -31.34   5 19 39.5  18.7 275.1  -41.9 157.1   47.6
    60.78 W   -30.76   5 19 46.7  20.3 275.8  -43.0 159.1   48.5
    62.49 W   -30.13   5 19 54.5  21.8 276.5  -44.1 161.0   49.4
    64.17 W   -29.45   5 20  2.8  23.3 277.1  -45.2 162.9   50.2
    65.81 W   -28.72   5 20 11.6  24.7 277.6  -46.3 164.9   51.1
    67.41 W   -27.94   5 20 20.9  26.2 278.1  -47.4 166.9   51.9
    68.97 W   -27.11   5 20 30.8  27.7 278.5  -48.5 168.8   52.8
    70.49 W   -26.24   5 20 41.1  29.1 278.8  -49.6 170.8   53.6
    71.96 W   -25.33   5 20 51.9  30.5 279.0  -50.6 172.8   54.4
    73.40 W   -24.38   5 21  3.1  31.9 279.1  -51.7 174.8   55.2
    78.72 W   -20.20   5 21 52.3  37.2 278.8  -56.0 183.1   58.1
    87.43 W   -10.41   5 23 48.2  46.2 273.0  -63.9 202.6   62.6
    93.19 W    -0.72   5 25 42.6  51.1 262.2  -69.0 225.8   64.2
    97.42 W     9.65   5 27 42.1  52.0 248.0  -70.9 255.7   63.2
    98.37 W    12.70   5 28 16.2  51.5 243.9  -70.7 264.6   62.4
    98.79 W    14.24   5 28 33.1  51.1 241.9  -70.4 268.9   62.0
    99.19 W    15.78   5 28 49.9  50.6 240.0  -70.1 273.1   61.5
    99.56 W    17.33   5 29  6.6  50.1 238.1  -69.6 277.2   60.9
    99.89 W    18.88   5 29 23.1  49.4 236.3  -69.1 281.0   60.4
   100.20 W    20.44   5 29 39.5  48.7 234.6  -68.6 284.8   59.8
   100.47 W    22.01   5 29 55.7  48.0 233.0  -67.9 288.3   59.1
   100.71 W    23.57   5 30 11.7  47.1 231.5  -67.3 291.7   58.5
   100.92 W    25.14   5 30 27.5  46.2 230.1  -66.5 294.9   57.8
   101.09 W    26.72   5 30 43.0  45.3 228.7  -65.7 297.9   57.1
   101.22 W    28.29   5 30 58.3  44.3 227.5  -64.9 300.8   56.3
   101.32 W    29.87   5 31 13.3  43.2 226.3  -64.0 303.6   55.6
   101.38 W    31.45   5 31 27.9  42.1 225.3  -63.1 306.2   54.8
   101.39 W    33.02   5 31 42.3  41.0 224.4  -62.2 308.7   54.0
   101.36 W    34.60   5 31 56.3  39.8 223.5  -61.3 311.1   53.2
   101.29 W    36.17   5 32 10.0  38.6 222.8  -60.3 313.3   52.4
   101.16 W    37.74   5 32 23.3  37.3 222.2  -59.3 315.6   51.5
   100.98 W    39.31   5 32 36.3  36.0 221.6  -58.3 317.7   50.7
   100.75 W    40.87   5 32 48.8  34.7 221.2  -57.2 319.8   49.8
   100.45 W    42.43   5 33  0.9  33.4 220.9  -56.2 321.8   49.0
   100.09 W    43.98   5 33 12.6  32.0 220.6  -55.1 323.8   48.1
    99.65 W    45.52   5 33 23.8  30.6 220.5  -54.1 325.8   47.2
    99.14 W    47.06   5 33 34.6  29.2 220.5  -53.0 327.8   46.4
    98.55 W    48.58   5 33 44.9  27.7 220.6  -51.9 329.7   45.5
    97.86 W    50.09   5 33 54.8  26.3 220.9  -50.8 331.7   44.6
    97.07 W    51.58   5 34  4.1  24.8 221.2  -49.8 333.8   43.7
    96.17 W    53.05   5 34 12.9  23.3 221.7  -48.7 335.8   42.8
    95.15 W    54.50   5 34 21.2  21.8 222.4  -47.6 338.0   41.9
    93.99 W    55.93   5 34 29.0  20.3 223.2  -46.5 340.2   41.0
    92.69 W    57.33   5 34 36.2  18.8 224.1  -45.4 342.5   40.1
    89.56 W    60.03   5 34 49.1  15.7 226.6  -43.2 347.4   38.4
    80.77 W    64.87   5 35  7.9   9.5 234.2  -38.9 359.3   34.9
 
 CENTER FOR   105 Artemis     SAO      0  DATE 1998 FEB 12
 W. LONG.   LAT.     W. LONG.   LAT.     W. LONG.   LAT.     W. LONG.   LAT.
  100.772  24  0.0    101.392  33  0.0    100.539  42  0.0     97.389  51  0.0
  100.901  25  0.0    101.380  34  0.0    100.326  43  0.0     96.825  52  0.0
  101.016  26  0.0    101.348  35  0.0    100.083  44  0.0     96.204  53  0.0
  101.116  27  0.0    101.298  36  0.0     99.810  45  0.0     95.519  54  0.0
  101.202  28  0.0    101.227  37  0.0     99.504  46  0.0     94.765  55  0.0
  101.272  29  0.0    101.136  38  0.0     99.163  47  0.0     93.933  56  0.0
  101.327  30  0.0    101.022  39  0.0     98.784  48  0.0      0.000   0  0.0
  101.366  31  0.0    100.886  40  0.0     98.365  49  0.0      0.000   0  0.0
  101.388  32  0.0    100.725  41  0.0     97.901  50  0.0      0.000   0  0.0
 
 AT U.T.  5 30  0, W. LONG.=  100.540, LAT.=  22.424
 AT U.T.  5 31  0, W. LONG.=  101.237, LAT.=  28.474
 AT U.T.  5 32  0, W. LONG.=  101.348, LAT.=  35.016
 AT U.T.  5 33  0, W. LONG.=  100.475, LAT.=  42.314
 AT U.T.  5 34  0, W. LONG.=   97.434, LAT.=  50.917
 
MIN. GEOCENTRIC Shift from nom.       Prediction Comparison
U. T.   SEP.   Path  time
h   m    "    widths  m        
5 26.5  2.97E  0.0   0.0 E. Goffin nominal prediction, Feb. S&T, p. 86
5 27.1  2.78E  2.2W +0.6 USNO Flagstaff, 6 obs. 1998 Jan. 24-30
5 27.2  2.69E  3.2W +0.7 USNO Flagstaff, 18 obs. 1997Nov.22 - 1998Jan.30
5 27.2  2.68E  3.3W +0.7 USNO Flagstaff, 18 obs. 1997Nov.22 - 1998Feb. 2
5 27.6  2.74E  2.6W +1.1 USNO Flagstaff, 1 obs. 1998Feb. 2 (same CCD)   
5 27.1  2.76E  2.4W +0.6 USNO Flagstaff, 7 obs. 1998Jan.24 - 1998Feb. 2

The 3rd line (path 3.2 widths W) is the prediction in my Feb. 6th message
while the last line is my final prediction.

David Dunham, IOTA, 1998 February 11, 6h UT