IOTA/IOTA-ES occultation update for (930) Westphalia / 2UCAC 27014455 event on 2012 Sep 14, 17:54 UT Visible from Japan, China, Russia Summary ------- On 2012 Sep 14 UT, the 40 km diameter asteroid (930) Westphalia will occult a 11.2 mag star in the constellation Capricornus for observers along a path across Japan, China, Russia. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.0 mag to 14.1 mag (the magnitude of the asteroid) for at most 4.7 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 64 * date and approx. time of event: 2012 Sep 14, 17:48 - 2012 Sep 14, 17:58 UT * geocentric midpoint of event [JD]: 2456185.2455125 * magnitude of target star: 11.2 * magnitude drop [mag]: 3.0 * estimated maximum duration [s]: 4.7 * Moon: 3 % sunlit, 171° distance * Sun: 155° distance * rough path description: Japan, China, Russia The occultation path -------------------- * approximate projected width [km]: 93 * 1 sigma uncertainty interval [path widths]: +/- 0.95 * 1 sigma uncertainty interval [seconds]: +/- 4.2 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .047 +/- .039) * 1 sigma uncertainty ellipse (major, minor, PA): ( .049", .037", 64° ) * approx speed of asteroid's shadow [km/s]: 8.3167 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 27014455 by 930 Westphalia on 2012 Sep 14 Centre Star Star Sun Path Limits Error Limits E. Longitude Latitude U.T. Alt Az Alt Limit 1 Limit 2 Limit 3 Limit 4 o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " Longitude Longitude Longitude Longitude 66 58 2 76 0 0 17 58 58 0 181 -10 68 44 30 65 13 13 72 12 3 ... .. .. 67 1 57 75 0 0 17 58 58 1 181 -11 68 41 33 65 23 47 71 55 23 ... .. .. 67 13 37 74 0 0 17 58 57 2 181 -12 68 47 22 65 41 11 71 49 31 ... .. .. 67 31 47 73 0 0 17 58 55 3 182 -13 69 0 27 66 4 18 71 52 33 ... .. .. 67 55 28 72 0 0 17 58 53 4 182 -14 69 19 42 66 32 18 72 3 5 63 56 58 68 23 55 71 0 0 17 58 50 5 182 -15 69 44 17 67 4 33 72 20 2 64 36 15 68 56 33 70 0 0 17 58 47 6 183 -16 70 13 30 67 40 32 72 42 33 65 18 28 69 32 54 69 0 0 17 58 43 7 183 -17 70 46 50 68 19 52 73 9 58 66 3 19 70 12 38 68 0 0 17 58 39 8 184 -18 71 23 52 69 2 14 73 41 46 66 50 37 70 55 26 67 0 0 17 58 34 9 185 -19 72 4 17 69 47 23 74 17 31 67 40 10 71 41 5 66 0 0 17 58 28 10 186 -20 72 47 48 70 35 9 74 56 54 68 31 51 72 29 25 65 0 0 17 58 22 11 186 -21 73 34 14 71 25 21 75 39 39 69 25 34 73 20 17 64 0 0 17 58 15 12 187 -22 74 23 24 72 17 53 76 25 34 70 21 14 74 13 35 63 0 0 17 58 8 13 188 -23 75 15 13 73 12 41 77 14 29 71 18 51 75 9 16 62 0 0 17 58 0 14 189 -24 76 9 34 74 9 42 78 6 17 72 18 20 76 7 17 61 0 0 17 57 51 15 190 -25 77 6 25 75 8 52 79 0 53 73 19 43 77 7 36 60 0 0 17 57 42 16 191 -26 78 5 43 76 10 13 79 58 14 74 23 0 78 10 14 59 0 0 17 57 32 17 192 -27 79 7 28 77 13 44 80 58 20 75 28 12 79 15 12 58 0 0 17 57 21 18 193 -28 80 11 41 78 19 27 82 1 10 76 35 22 80 22 34 57 0 0 17 57 10 19 194 -30 81 18 26 79 27 25 83 6 46 77 44 33 81 32 22 56 0 0 17 56 58 19 196 -31 82 27 45 80 37 44 84 15 13 78 55 50 82 44 43 55 0 0 17 56 45 20 197 -32 83 39 45 81 50 27 85 26 37 80 9 19 83 59 43 54 0 0 17 56 32 21 198 -33 84 54 32 83 5 42 86 41 3 81 25 6 85 17 32 53 0 0 17 56 18 22 200 -34 86 12 16 84 23 38 87 58 43 82 43 20 86 38 20 52 0 0 17 56 3 22 201 -35 87 33 7 85 44 24 89 19 48 84 4 9 88 2 19 51 0 0 17 55 47 23 203 -36 88 57 19 87 8 14 90 44 34 85 27 46 89 29 45 50 0 0 17 55 31 23 204 -37 90 25 9 88 35 20 92 13 18 86 54 24 91 0 58 49 0 0 17 55 14 24 206 -38 91 56 56 90 6 2 93 46 25 88 24 18 92 36 19 48 0 0 17 54 56 24 208 -39 93 33 5 91 40 41 95 24 22 89 57 49 94 16 18 47 0 0 17 54 36 25 209 -40 95 14 8 93 19 43 97 7 47 91 35 18 96 1 30 46 0 0 17 54 16 25 211 -41 97 0 42 95 3 40 98 57 25 93 17 14 97 52 39 45 0 0 17 53 55 25 213 -42 98 53 37 96 53 14 100 54 18 95 4 11 99 50 44 44 0 0 17 53 33 25 215 -42 100 53 59 98 49 17 102 59 48 96 56 54 101 57 3 43 0 0 17 53 9 25 218 -43 103 3 15 100 52 58 105 15 50 98 56 20 Latitude Latitude Latitude Latitude 102 0 0 42 58 39 17 53 9 25 218 -43 43 28 47 42 29 10 44 28 1 41 34 46 103 0 0 42 31 41 17 52 58 25 219 -43 43 1 27 42 2 33 43 59 54 41 8 46 104 0 0 42 5 40 17 52 46 25 220 -43 42 35 5 41 36 51 43 32 48 40 43 39 105 0 0 41 40 36 17 52 36 25 221 -44 42 9 41 41 12 6 43 6 43 40 19 25 106 0 0 41 16 28 17 52 25 25 222 -44 41 45 15 40 48 15 42 41 38 39 56 5 107 0 0 40 53 15 17 52 14 25 223 -44 41 21 45 40 25 19 42 17 32 39 33 38 108 0 0 40 30 59 17 52 4 24 224 -44 40 59 12 40 3 18 41 54 24 39 12 3 109 0 0 40 9 37 17 51 53 24 225 -44 40 37 35 39 42 10 41 32 16 38 51 22 110 0 0 39 49 10 17 51 43 24 226 -44 40 16 54 39 21 57 41 11 5 38 31 32 111 0 0 39 29 38 17 51 33 24 227 -44 39 57 8 39 2 38 40 50 51 38 12 36 112 0 0 39 11 1 17 51 23 23 227 -44 39 38 18 38 44 13 40 31 35 37 54 31 113 0 0 38 53 18 17 51 13 23 228 -44 39 20 24 38 26 41 40 13 16 37 37 19 114 0 0 38 36 29 17 51 3 22 229 -43 39 3 24 38 10 2 39 55 54 37 20 59 115 0 0 38 20 34 17 50 54 22 230 -43 38 47 19 37 54 17 39 39 28 37 5 31 116 0 0 38 5 34 17 50 45 22 231 -43 38 32 8 37 39 25 39 23 58 36 50 55 117 0 0 37 51 26 17 50 36 21 232 -43 38 17 53 37 25 27 39 9 25 36 37 11 118 0 0 37 38 13 17 50 27 21 233 -42 38 4 31 37 12 21 38 55 47 36 24 18 119 0 0 37 25 54 17 50 18 20 234 -42 37 52 4 37 0 8 38 43 5 36 12 18 120 0 0 37 14 28 17 50 10 20 234 -42 37 40 32 36 48 49 38 31 19 36 1 9 121 0 0 37 3 55 17 50 1 19 235 -41 37 29 54 36 38 22 38 20 28 35 50 53 122 0 0 36 54 16 17 49 53 19 236 -41 37 20 9 36 28 48 38 10 33 35 41 28 123 0 0 36 45 31 17 49 46 18 237 -41 37 11 20 36 20 8 38 1 33 35 32 56 124 0 0 36 37 40 17 49 38 17 237 -40 37 3 24 36 12 20 37 53 29 35 25 15 125 0 0 36 30 42 17 49 31 17 238 -40 36 56 23 36 5 26 37 46 21 35 18 27 126 0 0 36 24 38 17 49 24 16 239 -39 36 50 16 35 59 25 37 40 8 35 12 30 127 0 0 36 19 28 17 49 17 16 240 -39 36 45 3 35 54 17 37 34 51 35 7 26 128 0 0 36 15 12 17 49 11 15 240 -38 36 40 46 35 50 2 37 30 29 35 3 15 129 0 0 36 11 50 17 49 4 14 241 -38 36 37 22 35 46 41 37 27 4 34 59 56 130 0 0 36 9 22 17 48 58 14 242 -37 36 34 54 35 44 14 37 24 34 34 57 29 131 0 0 36 7 49 17 48 53 13 242 -36 36 33 21 35 42 40 37 23 1 34 55 56 132 0 0 36 7 10 17 48 47 12 243 -36 36 32 42 35 42 1 37 22 24 34 55 15 133 0 0 36 7 25 17 48 42 12 244 -35 36 32 59 35 42 15 37 22 43 34 55 28 134 0 0 36 8 36 17 48 37 11 244 -34 36 34 12 35 43 24 37 24 0 34 56 34 135 0 0 36 10 42 17 48 33 10 245 -34 36 36 20 35 45 28 37 26 13 34 58 33 136 0 0 36 13 43 17 48 29 9 245 -33 36 39 24 35 48 27 37 29 23 35 1 26 137 0 0 36 17 41 17 48 25 9 246 -32 36 43 25 35 52 20 37 33 31 35 5 14 138 0 0 36 22 34 17 48 21 8 247 -32 36 48 22 35 57 9 37 38 37 35 9 56 139 0 0 36 28 23 17 48 18 7 247 -31 36 54 17 36 2 54 37 44 41 35 15 32 140 0 0 36 35 9 17 48 15 6 248 -30 37 1 8 36 9 34 37 51 44 35 22 3 141 0 0 36 42 52 17 48 12 6 249 -29 37 8 57 36 17 11 37 59 45 35 29 30 142 0 0 36 51 32 17 48 10 5 249 -29 37 17 44 36 25 45 38 8 46 35 37 52 143 0 0 37 1 9 17 48 8 4 250 -28 37 27 29 36 35 15 38 18 47 .. .. .. 144 0 0 37 11 45 17 48 7 3 250 -27 37 38 13 36 45 43 38 29 48 .. .. .. 145 0 0 37 23 20 17 48 5 2 251 -26 37 49 57 36 57 9 38 41 50 .. .. .. 146 0 0 37 35 53 17 48 5 2 252 -26 38 2 40 37 9 33 38 54 53 .. .. .. 147 0 0 37 49 26 17 48 4 1 252 -25 38 16 23 37 22 56 39 8 58 .. .. .. Uncertainty in time = +/- 5 secs Prediction of 2012 Sep 8.0 Data for the target star ------------------------ * name: 2UCAC 27014455 * constellation : Capricornus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 21 58 33.4042 DE: -13 39 45.621 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .026, .029 ) * V mag [mag]: 11.2 * B mag [mag]: 0.0 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (930) Westphalia approx. diameter [km]: 40 approx. diameter ["]: .047 distance from Earth [AU]: 1.16200 * orbital information: orbit source: Preston date of fit: 2012 Sep 07 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 901 number of rejected observations: 32 time covered by the observations: 1920 Mar 21 - 2012 Sep 01 1 sigma uncertainty ellipse (major, minor, PA): 0.043, 0.024, 55° remarks: * orbital elements for (930) Westphalia : Mean anomaly = 20.94824247 deg Arg. of pericenter = 329.55432714 deg Long. of node = 341.09633572 deg Inclination = 15.31742219 deg Eccentricity = 0.14223984 Semimajor axis = 2.43133320 AU Perihelion dist = 2.08550074 AU Mag: H = 11.09, G = 0.15 Epoch of elements : MJD 56184.74600000 TDT (2012 Sep 14.746) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 14 930 Westphalia 17h 53.5m UT 11.2 21 58 33.404-13 39 45.622UCAC 27014455 0.0 14.1 40 4.7 1.162 -2.199 15.26 67.1451 -13.665 -89.55 3.05 17.8923 0.38796 0.81430 -4.23919 2.01606 0.00209 0.00088 2000 19.7143842012 910.00000329.554327341.096336 15.3174220.14223984 2.4313332 2.085500811.4 5.00.15 RATE 2.5997850 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.049 0.037 64 1.95 0.045 0 0 2-1 056178.0020120914_014455 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Sep 07, 22:52 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org