Grazing Occultation of 1925 SB1 Magnitude 1.0v 1925 = Spica = alpha Virginis Date 2006 August 28 (Monday) Nominal site altitude 0m E. Longit. Latitude U.T. Sun Moon TanZ PA WA CA o ' " o ' " h m s Alt Alt Az o o o 114 0 0 -31 30 38 7 59 20 24 68 336 0.40 41.3 21.08 17.51N 114 10 0 -31 37 44 7 59 54 24 68 335 0.41 41.2 21.01 17.43N 114 20 0 -31 44 46 8 0 28 24 68 335 0.41 41.1 20.93 17.36N 114 30 0 -31 51 45 8 1 2 24 67 334 0.41 41.1 20.85 17.28N 114 40 0 -31 58 41 8 1 35 23 67 333 0.42 41.0 20.78 17.20N 114 50 0 -32 5 33 8 2 9 23 67 333 0.42 40.9 20.70 17.13N 115 0 0 -32 12 23 8 2 42 23 67 332 0.43 40.8 20.62 17.05N 115 10 0 -32 19 9 8 3 15 22 67 332 0.43 40.7 20.55 16.97N 115 20 0 -32 25 51 8 3 48 22 66 331 0.44 40.7 20.47 16.89N 115 30 0 -32 32 31 8 4 20 22 66 331 0.44 40.6 20.39 16.82N 115 40 0 -32 39 7 8 4 53 22 66 330 0.45 40.5 20.32 16.74N 115 50 0 -32 45 40 8 5 25 21 66 330 0.45 40.4 20.24 16.66N 116 0 0 -32 52 10 8 5 57 21 65 329 0.46 40.4 20.16 16.58N 116 10 0 -32 58 37 8 6 29 21 65 328 0.46 40.3 20.08 16.51N 116 20 0 -33 5 1 8 7 0 20 65 328 0.47 40.2 20.01 16.43N 116 30 0 -33 11 21 8 7 32 20 65 327 0.47 40.1 19.93 16.35N 116 40 0 -33 17 39 8 8 3 20 65 327 0.47 40.0 19.85 16.27N 116 50 0 -33 23 53 8 8 35 20 64 327 0.48 40.0 19.77 16.20N 117 0 0 -33 30 5 8 9 6 19 64 326 0.48 39.9 19.69 16.12N 117 10 0 -33 36 13 8 9 36 19 64 326 0.49 39.8 19.62 16.04N 117 20 0 -33 42 18 8 10 7 19 64 325 0.49 39.7 19.54 15.96N 117 30 0 -33 48 20 8 10 38 19 63 325 0.50 39.7 19.46 15.88N 117 40 0 -33 54 20 8 11 8 18 63 324 0.50 39.6 19.38 15.81N 117 50 0 -34 0 16 8 11 38 18 63 324 0.51 39.5 19.31 15.73N Path coordinates are referred to WGS84 (as used by GPS). 1925 is multiple : 1.3 4.5 0.050" 225.0 : 1.3 7.5 0.50" 180.0 : 0.9 12.0 148" 32.0 Graze Path of component #2 0.09km North, and 0.0 secs. earlier cf. primary. Graze Path of component #3 0.71km North, and 1.0 secs. later cf. primary. Graze Path of component #4 268.51km South, and 58.5 secs. earlier cf. primary. 1925 = alf Vir, 0.95 +/- 0.10 V , Type ELL+BCEP, Period 4.014604 days, Phase 0.24 Librations Long -4.26 Lat +3.00 P +19.1 D -4.0 Illumination of moon 17%+ Elongation of Moon 49 Vertical Profile Scale 1.92 km/arcsec at mean distance of moon Horizontal Scale Factor 1.28 deg/min Limiting Magnitudes for various telescope apertures (in mm) CA\Tdia 50 100 150 200 250 300 350 11.7 2.9 4.3 5.1 5.6 5.9 6.1 6.3 13.7 2.9 4.3 5.1 5.6 5.9 6.1 6.3 15.7 2.9 4.3 5.1 5.6 5.9 6.1 6.3 17.7 2.9 4.3 5.1 5.6 5.9 6.1 6.3 19.7 2.9 4.3 5.1 5.6 5.9 6.1 6.3