IOTA/IOTA-ES occultation update for (516) Amherstia / 2UCAC 25221932 event on 2012 Sep 14, 14:43 UT Visible from Japan, China, Russia Summary ------- On 2012 Sep 14 UT, the 66 km diameter asteroid (516) Amherstia will occult a 12.2 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 0.9 mag to 12.4 mag (the magnitude of the asteroid) for at most 11.0 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: 80 * date and approx. time of event: 2012 Sep 14, 14:35 - 2012 Sep 14, 14:55 UT * geocentric midpoint of event [JD]: 2456185.114825 * magnitude of target star: 12.2 * magnitude drop [mag]: 0.9 * estimated maximum duration [s]: 11.0 * Moon: 3 % sunlit, 159° distance * Sun: 141° distance * rough path description: Japan, China, Russia The occultation path -------------------- * approximate projected width [km]: 117 * 1 sigma uncertainty interval [path widths]: +/- 0.68 * 1 sigma uncertainty interval [seconds]: +/- 7.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .035 +/- .035) * 1 sigma uncertainty ellipse (major, minor, PA): ( .035", .035", 357° ) * approx speed of asteroid's shadow [km/s]: 6.0462 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 25221932 by 516 Amherstia 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 78 44 43 71 0 0 14 55 13 1 162 -7 80 29 20 77 0 43 82 52 46 ... .. .. 79 46 31 70 0 0 14 55 13 2 163 -8 81 26 34 78 7 4 83 43 48 ... .. .. 80 47 35 69 0 0 14 55 11 3 164 -9 82 23 34 79 12 12 84 35 14 ... .. .. 81 48 7 68 0 0 14 55 9 4 165 -10 83 20 27 80 16 25 85 27 7 ... .. .. 82 48 18 67 0 0 14 55 7 5 166 -11 84 17 19 81 19 53 86 19 28 79 20 30 83 48 15 66 0 0 14 55 4 6 167 -12 85 14 16 82 22 49 87 12 21 80 27 31 84 48 5 65 0 0 14 55 0 7 168 -13 86 11 24 83 25 22 88 5 46 81 33 45 85 47 56 64 0 0 14 54 55 8 168 -14 87 8 47 84 27 41 88 59 47 82 39 25 86 47 53 63 0 0 14 54 50 9 169 -15 88 6 29 85 29 53 89 54 26 83 44 40 87 48 2 62 0 0 14 54 44 10 170 -16 89 4 35 86 32 4 90 49 45 84 49 39 88 48 27 61 0 0 14 54 38 11 171 -17 90 3 9 87 34 22 91 45 47 85 54 28 89 49 14 60 0 0 14 54 30 12 172 -18 91 2 14 88 36 50 92 42 33 86 59 16 90 50 27 59 0 0 14 54 22 13 173 -19 92 1 54 89 39 36 93 40 7 88 4 8 91 52 10 58 0 0 14 54 14 14 174 -20 93 2 13 90 42 44 94 38 32 89 9 11 92 54 28 57 0 0 14 54 4 15 175 -21 94 3 14 91 46 18 95 37 49 90 14 30 93 57 24 56 0 0 14 53 54 16 176 -22 95 5 1 92 50 23 96 38 2 91 20 11 95 1 2 55 0 0 14 53 43 17 177 -23 96 7 37 93 55 5 97 39 14 92 26 19 96 5 28 54 0 0 14 53 31 18 178 -24 97 11 7 95 0 27 98 41 28 93 32 59 97 10 45 53 0 0 14 53 19 20 179 -25 98 15 34 96 6 34 99 44 48 94 40 15 98 16 57 52 0 0 14 53 6 21 180 -27 99 21 2 97 13 31 100 49 18 95 48 14 99 24 10 51 0 0 14 52 52 22 181 -28 100 27 37 98 21 23 101 55 2 96 57 0 100 32 28 50 0 0 14 52 37 22 182 -29 101 35 22 99 30 14 103 2 5 98 6 38 101 41 55 49 0 0 14 52 21 23 183 -30 102 44 22 100 40 10 104 10 30 99 17 13 102 52 38 48 0 0 14 52 5 24 185 -31 103 54 44 101 51 15 105 20 24 100 28 52 104 4 42 47 0 0 14 51 48 25 186 -33 105 6 32 103 3 37 106 31 53 101 41 39 105 18 14 46 0 0 14 51 30 26 187 -34 106 19 53 104 17 21 107 45 2 102 55 41 106 33 19 45 0 0 14 51 11 27 188 -35 107 34 54 105 32 33 109 0 0 104 11 5 107 50 7 44 0 0 14 50 51 28 190 -37 108 51 42 106 49 21 110 16 53 105 27 57 109 8 44 43 0 0 14 50 30 29 191 -38 110 10 26 108 7 53 111 35 52 106 46 25 110 29 20 42 0 0 14 50 9 30 193 -39 111 31 16 109 28 17 112 57 5 108 6 38 111 52 5 41 0 0 14 49 46 30 194 -41 112 54 23 110 50 44 114 20 46 109 28 45 113 17 10 40 0 0 14 49 22 31 196 -42 114 19 57 112 15 25 115 47 6 110 52 56 114 44 50 39 0 0 14 48 58 32 197 -43 115 48 14 113 42 30 117 16 21 112 19 22 116 15 18 38 0 0 14 48 32 32 199 -45 117 19 30 115 12 16 118 48 49 113 48 17 117 48 52 37 0 0 14 48 6 33 201 -46 118 54 2 116 44 58 120 24 52 115 19 55 119 25 54 36 0 0 14 47 38 33 203 -48 120 32 15 118 20 55 122 4 53 116 54 35 121 6 46 35 0 0 14 47 9 34 205 -49 122 14 33 120 0 30 123 49 25 118 32 35 122 51 59 34 0 0 14 46 38 34 207 -51 124 1 31 121 44 9 125 39 3 120 14 19 124 42 9 33 0 0 14 46 6 34 209 -52 125 53 48 123 32 24 127 34 37 122 0 18 126 38 1 32 0 0 14 45 33 34 211 -54 127 52 14 125 25 57 129 37 6 123 51 4 128 40 32 31 0 0 14 44 58 34 213 -55 129 57 57 127 25 38 131 47 52 125 47 22 Latitude Latitude Latitude Latitude 129 0 0 30 50 48 14 44 53 34 214 -55 31 27 11 30 15 2 32 17 47 29 27 21 130 0 0 30 22 58 14 44 36 34 215 -56 30 59 3 29 47 31 31 49 11 29 0 13 131 0 0 29 56 0 14 44 19 34 216 -56 30 31 47 29 20 49 31 21 29 28 33 54 132 0 0 29 29 52 14 44 2 34 217 -57 30 5 22 28 54 58 30 54 39 28 8 23 133 0 0 29 4 34 14 43 45 34 218 -58 29 39 48 28 29 56 30 28 41 27 43 41 134 0 0 28 40 7 14 43 29 34 219 -58 29 15 5 28 5 43 30 3 36 27 19 48 135 0 0 28 16 31 14 43 12 33 220 -59 28 51 14 27 42 21 29 39 23 26 56 43 136 0 0 27 53 44 14 42 56 33 221 -59 28 28 13 27 19 48 29 16 2 26 34 27 137 0 0 27 31 48 14 42 40 33 222 -59 28 6 3 26 58 4 28 53 33 26 13 0 138 0 0 27 10 41 14 42 24 33 223 -60 27 44 44 26 37 10 28 31 56 25 52 21 139 0 0 26 50 25 14 42 8 32 224 -60 27 24 16 26 17 5 28 11 10 25 32 31 140 0 0 26 30 58 14 41 53 32 225 -60 27 4 38 25 57 49 27 51 16 25 13 29 141 0 0 26 12 22 14 41 38 32 226 -61 26 45 51 25 39 23 27 32 13 24 55 16 142 0 0 25 54 35 14 41 22 31 227 -61 26 27 54 25 21 46 27 14 2 24 37 51 143 0 0 25 37 38 14 41 7 31 228 -61 26 10 48 25 4 58 26 56 42 24 21 15 144 0 0 25 21 31 14 40 53 30 228 -61 25 54 32 24 48 59 26 40 14 24 5 28 145 0 0 25 6 14 14 40 38 30 229 -61 25 39 6 24 33 50 26 24 36 23 50 28 146 0 0 24 51 47 14 40 24 29 230 -61 25 24 31 24 19 30 26 9 50 23 36 18 147 0 0 24 38 9 14 40 10 29 231 -61 25 10 47 24 5 59 25 55 55 23 22 56 148 0 0 24 25 21 14 39 56 28 232 -61 24 57 52 23 53 17 25 42 51 23 10 22 149 0 0 24 13 23 14 39 43 28 232 -61 24 45 48 23 41 25 25 30 39 22 58 37 150 0 0 24 2 15 14 39 29 27 233 -61 24 34 34 23 30 22 25 19 17 22 47 41 151 0 0 23 51 57 14 39 17 27 234 -61 24 24 11 23 20 8 25 8 47 22 37 34 152 0 0 23 42 28 14 39 4 26 235 -60 24 14 38 23 10 44 24 59 8 22 28 15 153 0 0 23 33 50 14 38 51 25 235 -60 24 5 56 23 2 10 24 50 20 22 19 45 154 0 0 23 26 2 14 38 39 25 236 -60 23 58 5 22 54 25 24 42 24 22 12 4 155 0 0 23 19 4 14 38 27 24 237 -60 23 51 4 22 47 30 24 35 19 22 5 13 156 0 0 23 12 57 14 38 16 23 237 -59 23 44 54 22 41 24 24 29 6 21 59 10 157 0 0 23 7 40 14 38 5 23 238 -59 23 39 36 22 36 9 24 23 45 21 53 57 158 0 0 23 3 13 14 37 54 22 238 -58 23 35 8 22 31 44 24 19 16 21 49 34 159 0 0 22 59 38 14 37 43 21 239 -58 23 31 32 22 28 9 24 15 38 21 46 0 160 0 0 22 56 53 14 37 33 20 240 -57 23 28 47 22 25 25 24 12 53 21 43 16 161 0 0 22 55 0 14 37 23 20 240 -57 23 26 54 22 23 31 24 11 0 21 41 22 162 0 0 22 53 58 14 37 14 19 241 -56 23 25 53 22 22 28 24 10 0 21 40 18 163 0 0 22 53 47 14 37 4 18 241 -55 23 25 43 22 22 16 24 9 53 21 40 4 164 0 0 22 54 28 14 36 56 17 242 -55 23 26 27 22 22 56 24 10 39 21 40 41 165 0 0 22 56 2 14 36 47 17 242 -54 23 28 3 22 24 27 24 12 18 21 42 10 166 0 0 22 58 28 14 36 39 16 243 -53 23 30 31 22 26 50 24 14 51 21 44 29 167 0 0 23 1 46 14 36 31 15 243 -53 23 33 53 22 30 5 24 18 18 21 47 39 168 0 0 23 5 57 14 36 24 14 244 -52 23 38 9 22 34 12 24 22 39 21 51 42 169 0 0 23 11 2 14 36 17 13 244 -51 23 43 18 22 39 13 24 27 55 21 56 36 170 0 0 23 17 0 14 36 11 12 244 -51 23 49 21 22 45 6 24 34 6 22 2 23 171 0 0 23 23 52 14 36 4 12 245 -50 23 56 19 22 51 52 24 41 12 22 9 2 172 0 0 23 31 39 14 35 59 11 245 -49 24 4 12 22 59 33 24 49 14 22 16 35 173 0 0 23 40 20 14 35 53 10 246 -48 24 13 0 23 8 7 24 58 12 22 25 0 174 0 0 23 49 56 14 35 49 9 246 -47 24 22 44 23 17 36 25 8 7 22 34 20 175 0 0 24 0 28 14 35 44 8 247 -46 24 33 24 23 28 0 25 18 59 22 44 33 176 0 0 24 11 55 14 35 40 7 247 -46 24 45 0 23 39 19 25 30 48 22 55 41 177 0 0 24 24 19 14 35 37 6 247 -45 24 57 34 23 51 34 25 43 35 23 7 45 178 0 0 24 37 40 14 35 34 5 248 -44 25 11 5 24 4 45 25 57 21 23 20 43 179 0 0 24 51 59 14 35 31 4 248 -43 25 25 34 24 18 53 26 12 6 .. .. .. 180 0 0 25 7 15 14 35 29 4 249 -42 25 41 2 24 33 58 26 27 51 .. .. .. -179 0 0 25 23 30 14 35 27 3 249 -41 25 57 29 24 50 1 26 44 36 .. .. .. -178 0 0 25 40 43 14 35 26 2 250 -40 26 14 56 25 7 2 27 2 22 .. .. .. -177 0 0 25 58 56 14 35 26 1 250 -39 26 33 23 25 25 1 27 21 9 .. .. .. Uncertainty in time = +/- 7 secs Prediction of 2012 Sep 8.0 Data for the target star ------------------------ * name: 2UCAC 25221932 * constellation : Capricornus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 21 01 15.5069 DE: -17 40 29.674 * position source: mpos:UCAC4 pm:UCAC4 * standard error: RA,DE ["]: ( .027, .034 ) * V mag [mag]: 12.2 * B mag [mag]: 0.0 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (516) Amherstia approx. diameter [km]: 66 approx. diameter ["]: .052 distance from Earth [AU]: 1.74200 * orbital information: orbit source: Preston date of fit: 2012 Sep 07 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1020 number of rejected observations: 103 time covered by the observations: 1903 Nov 14 - 2012 Sep 04 1 sigma uncertainty ellipse (major, minor, PA): 0.023, 0.012, 61° remarks: * orbital elements for (516) Amherstia : Mean anomaly = 68.15566586 deg Arg. of pericenter = 258.21149358 deg Long. of node = 328.85777014 deg Inclination = 12.96018690 deg Eccentricity = 0.27331606 Semimajor axis = 2.67983257 AU Perihelion dist = 1.94739130 AU Mag: H = 8.21, G = 0.15 Epoch of elements : MJD 56184.61300000 TDT (2012 Sep 14.613) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 14 516 Amherstia 14h 45.3m UT 12.2 21 1 15.507-17 40 29.672UCAC 25221932 0.0 12.4 66 11.0 1.742 -1.061 8.12 99.9966 -17.676 -42.49 3.10 14.7558 0.38895 0.72667 -3.00988 1.60840 0.00341 0.00106 2000 67.1192692012 910.00000258.211494328.857770 12.9601870.27331606 2.6798326 1.9473913 8.3 5.00.15 RATE 2.2466870 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.035 0.035 357 1.68 0.035 0 0-1-4 056178.0020120914_221932 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Sep 07, 22:51 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org