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 145 0 0 -42 15 48 9 4 19 32 285 1.58 29.0 8.80 5.22N 145 10 0 -42 16 47 9 4 31 32 285 1.59 28.9 8.75 5.17N 145 20 0 -42 17 44 9 4 43 32 285 1.60 28.9 8.71 5.12N 145 30 0 -42 18 41 9 4 54 32 285 1.61 28.8 8.66 5.07N 145 40 0 -42 19 36 9 5 6 32 285 1.62 28.8 8.61 5.02N 145 50 0 -42 20 31 9 5 17 32 284 1.63 28.8 8.56 4.98N 146 0 0 -42 21 24 9 5 28 31 284 1.64 28.7 8.51 4.93N 146 10 0 -42 22 16 9 5 40 31 284 1.65 28.7 8.47 4.88N 146 20 0 -42 23 7 9 5 51 31 284 1.66 28.6 8.42 4.83N 146 30 0 -42 23 57 9 6 2 31 284 1.67 28.6 8.37 4.79N 146 40 0 -42 24 46 9 6 13 31 284 1.68 28.5 8.33 4.74N 146 50 0 -42 25 34 9 6 24 31 283 1.69 28.5 8.28 4.69N 147 0 0 -42 26 21 9 6 35 30 283 1.70 28.4 8.23 4.65N 147 10 0 -42 27 7 9 6 46 30 283 1.71 28.4 8.19 4.60N 147 20 0 -42 27 52 9 6 57 30 283 1.72 28.3 8.14 4.55N 147 30 0 -42 28 35 9 7 7 30 283 1.73 28.3 8.09 4.51N 147 40 0 -42 29 18 9 7 18 30 283 1.74 28.2 8.05 4.46N 147 50 0 -42 30 0 9 7 29 30 283 1.75 28.2 8.00 4.42N 148 0 0 -42 30 40 9 7 39 30 282 1.77 28.1 7.96 4.37N 148 10 0 -42 31 20 9 7 50 29 282 1.78 28.1 7.91 4.32N 148 20 0 -42 31 59 9 8 0 29 282 1.79 28.1 7.87 4.28N 148 30 0 -42 32 36 9 8 10 29 282 1.80 28.0 7.82 4.23N 148 40 0 -42 33 13 9 8 21 29 282 1.81 28.0 7.78 4.19N 148 50 0 -42 33 48 9 8 31 29 282 1.82 27.9 7.73 4.14N 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 0.81km North, and 0.6 secs. later cf. primary. Graze Path of component #4 270.14km South, and 25.9 secs. later cf. primary. 1925 = alf Vir, 0.95 +/- 0.10 V , Type ELL+BCEP, Period 4.014604 days, Phase 0.25 Librations Long -4.74 Lat +3.01 P +7.5 D -3.4 Illumination of moon 17%+ Elongation of Moon 49 Vertical Profile Scale 1.92 km/arcsec at mean distance of moon Horizontal Scale Factor 1.58 deg/min Limiting Magnitudes for various telescope apertures (in mm) CA\Tdia 50 100 150 200 250 300 350 0.1 4.6 6.0 6.8 7.3 7.6 7.8 8.0 2.1 5.2 6.7 7.5 8.0 8.3 8.6 8.8 4.1 6.1 7.6 8.4 8.9 9.3 9.6 9.8 6.1 6.1 7.6 8.4 9.0 9.4 9.7 9.9 8.1 6.2 7.7 8.5 9.1 9.4 9.7 10.0