IOTA/IOTA-ES occultation update for (287) Nephthys / TYC 5269-01442-1 event on 2012 Oct 21, 15:31 UT Visible from China, India, Arabia Summary ------- On 2012 Oct 21 UT, the 66 km diameter asteroid (287) Nephthys will occult a 10.9 mag star in the constellation Cetus for observers along a path across China, India, Arabia. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.2 mag to 11.6 mag (the magnitude of the asteroid) for at most 7.8 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: 86 * date and approx. time of event: 2012 Oct 21, 15:22 - 2012 Oct 21, 15:41 UT * geocentric midpoint of event [JD]: 2456222.1471625 * magnitude of target star: 10.9 * magnitude drop [mag]: 1.2 * estimated maximum duration [s]: 7.8 * Moon: 44 % sunlit, 75° distance * Sun: 153° distance * rough path description: China, India, Arabia The occultation path -------------------- * approximate projected width [km]: 84 * 1 sigma uncertainty interval [path widths]: +/- 0.59 * 1 sigma uncertainty interval [seconds]: +/- 5.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .041 +/- .036) * 1 sigma uncertainty ellipse (major, minor, PA): ( .041", .036", 88° ) * approx speed of asteroid's shadow [km/s]: 8.4332 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5269-01442-1 by 287 Nephthys on 2012 Oct 21 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 ' " Latitude Latitude Latitude Latitude 29 0 0 13 39 29 15 41 28 12 103 -1 14 2 33 13 16 34 14 29 55 12 49 39 30 0 0 13 35 43 15 41 24 13 104 -2 13 58 45 13 12 48 14 26 5 12 45 55 31 0 0 13 32 29 15 41 21 13 104 -3 13 55 29 13 9 35 14 22 48 12 42 44 32 0 0 13 29 47 15 41 17 14 104 -4 13 52 47 13 6 54 14 20 5 12 40 4 33 0 0 13 27 38 15 41 13 15 104 -5 13 50 37 13 4 46 14 17 53 12 37 57 34 0 0 13 26 1 15 41 8 16 105 -6 13 48 59 13 3 10 14 16 15 12 36 21 35 0 0 13 24 56 15 41 3 17 105 -6 13 47 54 13 2 6 14 15 9 12 35 18 36 0 0 13 24 24 15 40 59 18 105 -7 13 47 21 13 1 34 14 14 35 12 34 47 37 0 0 13 24 23 15 40 54 19 106 -8 13 47 20 13 1 34 14 14 34 12 34 47 38 0 0 13 24 55 15 40 48 20 106 -9 13 47 51 13 2 6 14 15 5 12 35 19 39 0 0 13 25 58 15 40 43 21 106 -10 13 48 55 13 3 9 14 16 8 12 36 23 40 0 0 13 27 34 15 40 37 22 107 -11 13 50 30 13 4 45 14 17 43 12 37 58 41 0 0 13 29 40 15 40 31 23 107 -12 13 52 37 13 6 51 14 19 50 12 40 5 42 0 0 13 32 19 15 40 24 24 107 -13 13 55 15 13 9 30 14 22 29 12 42 43 43 0 0 13 35 29 15 40 18 24 108 -14 13 58 26 13 12 39 14 25 40 12 45 52 44 0 0 13 39 10 15 40 11 25 108 -15 14 2 7 13 16 20 14 29 22 12 49 32 45 0 0 13 43 22 15 40 4 26 109 -16 14 6 20 13 20 32 14 33 36 12 53 43 46 0 0 13 48 6 15 39 57 27 109 -17 14 11 4 13 25 14 14 38 21 12 58 25 47 0 0 13 53 20 15 39 50 28 109 -18 14 16 20 13 30 28 14 43 37 13 3 38 48 0 0 13 59 5 15 39 42 29 110 -19 14 22 6 13 36 12 14 49 24 13 9 21 49 0 0 14 5 21 15 39 34 30 110 -20 14 28 23 13 42 27 14 55 43 13 15 35 50 0 0 14 12 8 15 39 27 30 111 -21 14 35 10 13 49 13 15 2 32 13 22 19 51 0 0 14 19 25 15 39 18 31 111 -22 14 42 29 13 56 28 15 9 51 13 29 33 52 0 0 14 27 12 15 39 10 32 112 -23 14 50 17 14 4 14 15 17 42 13 37 18 53 0 0 14 35 29 15 39 1 33 112 -23 14 58 36 14 12 30 15 26 2 13 45 32 54 0 0 14 44 17 15 38 53 34 113 -24 15 7 25 14 21 16 15 34 53 13 54 16 55 0 0 14 53 34 15 38 44 35 113 -25 15 16 44 14 30 31 15 44 14 14 3 29 56 0 0 15 3 21 15 38 35 35 114 -26 15 26 33 14 40 17 15 54 5 14 13 12 57 0 0 15 13 37 15 38 25 36 115 -27 15 36 51 14 50 31 16 4 26 14 23 25 58 0 0 15 24 23 15 38 16 37 115 -28 15 47 39 15 1 15 16 15 16 14 34 6 59 0 0 15 35 38 15 38 6 38 116 -29 15 58 56 15 12 28 16 26 35 14 45 16 60 0 0 15 47 22 15 37 56 38 117 -30 16 10 42 15 24 9 16 38 24 14 56 56 61 0 0 15 59 34 15 37 47 39 118 -31 16 22 57 15 36 20 16 50 42 15 9 3 62 0 0 16 12 16 15 37 36 40 118 -32 16 35 41 15 48 58 17 3 29 15 21 39 63 0 0 16 25 25 15 37 26 40 119 -33 16 48 53 16 2 6 17 16 44 15 34 44 64 0 0 16 39 3 15 37 16 41 120 -34 17 2 33 16 15 41 17 30 28 15 48 16 65 0 0 16 53 9 15 37 5 42 121 -35 17 16 42 16 29 44 17 44 39 16 2 16 66 0 0 17 7 43 15 36 54 42 122 -36 17 31 18 16 44 15 17 59 19 16 16 44 67 0 0 17 22 44 15 36 44 43 123 -36 17 46 23 16 59 13 18 14 27 16 31 38 68 0 0 17 38 12 15 36 33 44 124 -37 18 1 54 17 14 39 18 30 2 16 47 1 69 0 0 17 54 8 15 36 22 44 125 -38 18 17 53 17 30 31 18 46 4 17 2 49 70 0 0 18 10 30 15 36 10 45 126 -39 18 34 18 17 46 50 19 2 34 17 19 5 71 0 0 18 27 19 15 35 59 45 127 -40 18 51 10 18 3 36 19 19 30 17 35 47 72 0 0 18 44 34 15 35 48 46 128 -41 19 8 29 18 20 48 19 36 52 17 52 55 73 0 0 19 2 15 15 35 36 47 129 -42 19 26 13 18 38 25 19 54 41 18 10 29 74 0 0 19 20 22 15 35 24 47 130 -43 19 44 23 18 56 29 20 12 55 18 28 28 75 0 0 19 38 54 15 35 13 48 131 -44 20 2 59 19 14 57 20 31 35 18 46 52 76 0 0 19 57 51 15 35 1 48 133 -45 20 22 0 19 33 51 20 50 41 19 5 42 77 0 0 20 17 13 15 34 49 48 134 -45 20 41 26 19 53 9 21 10 11 19 24 56 78 0 0 20 36 59 15 34 37 49 135 -46 21 1 16 20 12 52 21 30 6 19 44 34 79 0 0 20 57 10 15 34 25 49 136 -47 21 21 30 20 32 58 21 50 24 20 4 36 80 0 0 21 17 44 15 34 13 50 138 -48 21 42 8 20 53 28 22 11 7 20 25 2 81 0 0 21 38 41 15 34 0 50 139 -49 22 3 9 21 14 22 22 32 13 20 45 51 82 0 0 22 0 1 15 33 48 50 141 -50 22 24 33 21 35 38 22 53 42 21 7 2 83 0 0 22 21 44 15 33 36 50 142 -50 22 46 20 21 57 16 23 15 34 21 28 36 84 0 0 22 43 49 15 33 23 51 144 -51 23 8 29 22 19 17 23 37 48 21 50 32 85 0 0 23 6 15 15 33 11 51 145 -52 23 31 0 22 41 39 24 0 24 22 12 50 86 0 0 23 29 3 15 32 58 51 147 -53 23 53 52 23 4 23 24 23 21 22 35 28 87 0 0 23 52 11 15 32 46 51 148 -53 24 17 4 23 27 27 24 46 39 22 58 27 88 0 0 24 15 40 15 32 34 51 150 -54 24 40 37 23 50 51 25 10 17 23 21 47 89 0 0 24 39 28 15 32 21 51 151 -55 25 4 30 24 14 36 25 34 15 23 45 26 90 0 0 25 3 36 15 32 8 51 153 -56 25 28 42 24 38 39 25 58 33 24 9 25 91 0 0 25 28 2 15 31 56 51 154 -56 25 53 13 25 3 1 26 23 9 24 33 42 92 0 0 25 52 47 15 31 43 51 156 -57 26 18 2 25 27 41 26 48 3 24 58 17 93 0 0 26 17 49 15 31 31 51 158 -58 26 43 9 25 52 39 27 13 15 25 23 10 94 0 0 26 43 9 15 31 18 51 159 -58 27 8 33 26 17 54 27 38 45 25 48 20 95 0 0 27 8 45 15 31 6 51 161 -59 27 34 13 26 43 26 28 4 31 26 13 46 96 0 0 27 34 36 15 30 54 51 162 -59 28 0 10 27 9 13 28 30 32 26 39 29 97 0 0 28 0 44 15 30 41 51 164 -60 28 26 21 27 35 16 28 56 49 27 5 26 98 0 0 28 27 5 15 30 29 51 166 -60 28 52 47 28 1 33 29 23 21 27 31 39 99 0 0 28 53 41 15 30 17 50 167 -61 29 19 28 28 28 5 29 50 6 27 58 5 100 0 0 29 20 30 15 30 4 50 169 -61 29 46 21 28 54 50 30 17 5 28 24 45 101 0 0 29 47 32 15 29 52 50 170 -62 30 13 28 29 21 47 30 44 17 28 51 38 102 0 0 30 14 46 15 29 40 50 172 -62 30 40 46 29 48 57 31 11 40 29 18 42 103 0 0 30 42 11 15 29 28 49 173 -62 31 8 15 30 16 18 31 39 15 29 45 59 104 0 0 31 9 47 15 29 16 49 175 -63 31 35 55 30 43 49 32 7 0 30 13 25 105 0 0 31 37 32 15 29 4 48 176 -63 32 3 45 31 11 31 32 34 55 30 41 2 106 0 0 32 5 27 15 28 53 48 178 -63 32 31 44 31 39 22 33 2 59 31 8 48 107 0 0 32 33 30 15 28 41 48 179 -63 32 59 51 32 7 21 33 31 11 31 36 43 108 0 0 33 1 41 15 28 29 47 180 -64 33 28 6 32 35 27 33 59 30 32 4 45 109 0 0 33 29 58 15 28 18 47 182 -64 33 56 27 33 3 41 34 27 56 32 32 54 110 0 0 33 58 22 15 28 7 46 183 -64 34 24 54 33 32 1 34 56 28 33 1 9 111 0 0 34 26 51 15 27 56 46 184 -64 34 53 27 34 0 26 35 25 5 33 29 30 112 0 0 34 55 24 15 27 45 45 186 -64 35 22 3 34 28 55 35 53 46 33 57 56 113 0 0 35 24 0 15 27 34 45 187 -64 35 50 44 34 57 29 36 22 31 34 26 25 114 0 0 35 52 40 15 27 23 44 188 -63 36 19 27 35 26 5 36 51 18 34 54 58 115 0 0 36 21 22 15 27 12 43 190 -63 36 48 11 35 54 43 37 20 7 35 23 32 116 0 0 36 50 4 15 27 2 43 191 -63 37 16 57 36 23 23 37 48 56 35 52 8 117 0 0 37 18 47 15 26 52 42 192 -63 37 45 43 36 52 3 38 17 46 36 20 45 118 0 0 37 47 30 15 26 42 41 193 -63 38 14 29 37 20 43 38 46 35 36 49 22 119 0 0 38 16 11 15 26 32 41 194 -62 38 43 13 37 49 22 39 15 22 37 17 57 120 0 0 38 44 50 15 26 22 40 195 -62 39 11 55 38 17 58 39 44 7 37 46 31 121 0 0 39 13 27 15 26 12 40 196 -62 39 40 33 38 46 32 40 12 48 38 15 2 122 0 0 39 41 59 15 26 3 39 197 -61 40 9 8 39 15 2 40 41 26 38 43 30 123 0 0 40 10 27 15 25 54 38 199 -61 40 37 38 39 43 28 41 9 58 39 11 54 124 0 0 40 38 49 15 25 45 37 200 -60 41 6 2 40 11 49 41 38 25 39 40 12 125 0 0 41 7 5 15 25 36 37 201 -60 41 34 20 40 40 3 42 6 45 40 8 25 126 0 0 41 35 15 15 25 27 36 202 -59 42 2 30 41 8 11 42 34 57 40 36 31 127 0 0 42 3 16 15 25 19 35 203 -59 42 30 33 41 36 11 43 3 1 41 4 30 128 0 0 42 31 9 15 25 11 35 204 -58 42 58 27 42 4 3 43 30 57 41 32 20 129 0 0 42 58 53 15 25 3 34 205 -58 43 26 12 42 31 46 43 58 42 42 0 2 130 0 0 43 26 26 15 24 55 33 206 -57 43 53 46 42 59 19 44 26 18 42 27 34 131 0 0 43 53 49 15 24 47 33 206 -57 44 21 10 43 26 41 44 53 42 42 54 56 132 0 0 44 21 1 15 24 40 32 207 -56 44 48 21 43 53 53 45 20 54 43 22 7 133 0 0 44 48 0 15 24 32 31 208 -56 45 15 21 44 20 52 45 47 53 43 49 6 134 0 0 45 14 47 15 24 25 30 209 -55 45 42 7 44 47 39 46 14 40 44 15 53 135 0 0 45 41 20 15 24 18 30 210 -54 46 8 40 45 14 12 46 41 12 44 42 27 136 0 0 46 7 39 15 24 12 29 211 -54 46 34 59 45 40 32 47 7 30 45 8 47 137 0 0 46 33 43 15 24 5 28 212 -53 47 1 2 46 6 37 47 33 33 45 34 53 138 0 0 46 59 33 15 23 59 27 213 -52 47 26 51 46 32 27 47 59 20 46 0 44 139 0 0 47 25 6 15 23 53 27 214 -52 47 52 23 46 58 2 48 24 51 46 26 20 140 0 0 47 50 23 15 23 47 26 215 -51 48 17 39 47 23 20 48 50 5 46 51 40 141 0 0 48 15 23 15 23 42 25 215 -51 48 42 37 47 48 22 49 15 2 47 16 43 142 0 0 48 40 6 15 23 36 25 216 -50 49 7 19 48 13 6 49 39 41 47 41 30 143 0 0 49 4 32 15 23 31 24 217 -49 49 31 42 48 37 34 50 4 2 48 5 59 144 0 0 49 28 39 15 23 26 23 218 -49 49 55 47 49 1 43 50 28 4 48 30 11 145 0 0 49 52 27 15 23 21 23 219 -48 50 19 33 49 25 34 50 51 47 48 54 4 146 0 0 50 15 57 15 23 16 22 220 -47 50 43 0 49 49 6 51 15 11 49 17 39 147 0 0 50 39 7 15 23 12 21 221 -47 51 6 8 50 12 19 51 38 16 49 40 55 148 0 0 51 1 58 15 23 7 20 221 -46 51 28 56 50 35 12 52 1 0 50 3 52 149 0 0 51 24 29 15 23 3 20 222 -45 51 51 23 50 57 46 52 23 24 50 26 29 150 0 0 51 46 39 15 22 59 19 223 -45 52 13 31 51 19 59 52 45 28 50 48 46 151 0 0 52 8 29 15 22 55 18 224 -44 52 35 18 51 41 53 53 7 11 51 10 43 152 0 0 52 29 59 15 22 52 18 225 -43 52 56 44 52 3 26 53 28 32 51 32 20 153 0 0 52 51 8 15 22 48 17 226 -43 53 17 49 52 24 38 53 49 33 51 53 36 154 0 0 53 11 55 15 22 45 16 226 -42 53 38 33 52 45 29 54 10 13 52 14 32 155 0 0 53 32 22 15 22 42 16 227 -41 53 58 55 53 6 0 54 30 31 52 35 7 156 0 0 53 52 27 15 22 39 15 228 -41 54 18 57 53 26 9 54 50 27 52 55 20 157 0 0 54 12 11 15 22 36 14 229 -40 54 38 36 53 45 57 55 10 2 53 15 13 158 0 0 54 31 34 15 22 33 14 230 -40 54 57 55 54 5 23 55 29 15 53 34 44 159 0 0 54 50 34 15 22 31 13 231 -39 55 16 51 54 24 28 55 48 6 53 53 54 160 0 0 55 9 14 15 22 28 12 231 -38 55 35 26 54 43 12 56 6 36 54 12 42 161 0 0 55 27 31 15 22 26 12 232 -38 55 53 39 55 1 34 56 24 44 54 31 10 162 0 0 55 45 28 15 22 24 11 233 -37 56 11 31 55 19 35 56 42 30 54 49 15 163 0 0 56 3 2 15 22 22 11 234 -36 56 29 1 55 37 14 56 59 54 55 6 59 164 0 0 56 20 15 15 22 20 10 235 -36 56 46 9 55 54 31 57 16 57 55 24 22 165 0 0 56 37 6 15 22 18 9 236 -35 57 2 56 56 11 27 57 33 38 55 41 23 166 0 0 56 53 36 15 22 17 9 237 -35 57 19 21 56 28 2 57 49 58 55 58 3 167 0 0 57 9 45 15 22 15 8 237 -34 57 35 25 56 44 15 58 5 56 56 14 22 168 0 0 57 25 32 15 22 14 8 238 -33 57 51 7 57 0 7 58 21 32 56 30 19 169 0 0 57 40 58 15 22 12 7 239 -33 58 6 29 57 15 37 58 36 48 56 45 55 170 0 0 57 56 3 15 22 11 6 240 -32 58 21 29 57 30 47 58 51 42 57 1 10 171 0 0 58 10 47 15 22 10 6 241 -32 58 36 7 57 45 36 59 6 15 57 16 4 172 0 0 58 25 10 15 22 9 5 242 -31 58 50 26 58 0 3 59 20 27 57 30 38 173 0 0 58 39 12 15 22 9 5 242 -31 59 4 23 58 14 10 59 34 18 57 44 50 174 0 0 58 52 53 15 22 8 4 243 -30 59 17 59 58 27 56 59 47 49 57 58 41 175 0 0 59 6 14 15 22 7 3 244 -29 59 31 16 58 41 22 60 1 0 58 12 12 176 0 0 59 19 14 15 22 7 3 245 -29 59 44 11 58 54 27 60 13 50 58 25 23 177 0 0 59 31 55 15 22 6 2 246 -28 59 56 47 59 7 12 60 26 20 58 38 13 178 0 0 59 44 15 15 22 6 2 247 -28 60 9 2 59 19 37 60 38 29 58 50 44 179 0 0 59 56 15 15 22 6 1 248 -27 60 20 58 59 31 42 60 50 20 59 2 54 180 0 0 60 7 56 15 22 6 1 248 -27 60 32 34 59 43 27 61 1 50 59 14 44 -179 0 0 60 19 17 15 22 6 0 249 -26 60 43 51 59 54 52 .. .. .. 59 26 15 Uncertainty in time = +/- 5 secs Prediction of 2012 Oct 8.0 Data for the target star ------------------------ * name: TYC 5269-01442-1 * constellation : Cetus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 00 40 25.6946 DE: -10 01 49.284 * position source: mpos:UCAC4 pm:UCAC4 * standard error: RA,DE ["]: ( .039, .035 ) * V mag [mag]: 10.9 * B mag [mag]: 11.9 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (287) Nephthys approx. diameter [km]: 66 approx. diameter ["]: .063 distance from Earth [AU]: 1.44200 * orbital information: orbit source: Preston date of fit: 2012 Oct 07 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1894 number of rejected observations: 150 time covered by the observations: 1900 Sep 21 - 2012 Oct 03 1 sigma uncertainty ellipse (major, minor, PA): 0.013, 0.009, 74° remarks: * orbital elements for (287) Nephthys : Mean anomaly = 112.49894440 deg Arg. of pericenter = 117.92385403 deg Long. of node = 142.43767026 deg Inclination = 10.02789774 deg Eccentricity = 0.02319484 Semimajor axis = 2.35266680 AU Perihelion dist = 2.29809708 AU Mag: H = 8.27, G = 0.22 Epoch of elements : MJD 56221.64700000 TDT (2012 Oct 21.647) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Oct 21 287 Nephthys 15h 31.9m UT 10.9 0 40 25.695-10 1 49.28TYC 5269-01442-1 11.9 11.6 66 7.8 1.442 -1.805 -11.43 106.6460 -10.026 -56.84 -10.99 15.5319 -0.24478 0.57183 -4.37442 -1.87659 0.00159 0.00199 2000 112.04910520121020.00000117.923854142.437670 10.0278980.02319484 2.3526668 2.2980971 8.3 5.00.22 RATE 2.7312630 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.041 0.036 88 1.59 0.037 0 0-4-4 056208.0020121021_1442-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Oct 07, 19:12 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org