IOTA/IOTA-ES occultation update for (431) Nephele / UCAC4 334-147192 event on 2023 Sep 28, 03:55 UT Visible from SW USA Summary ------- On 2023 Sep 28 UT, the 91.6 km diameter asteroid (431) Nephele will occult a 12.6 mag star in the constellation Sagittarius for observers along a path across SW USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.84 mag to 14.21 mag (the magnitude of the asteroid) for at most 5.120 seconds. This update is based on, astrometry for the asteroid kindly provided by the IAU Minor Planet Center. This work has made use of data from the European Space Agency (ESA) mission Gaia (http://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, http://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. The event at a glimpse ---------------------- * Rank: 100 * date and approx. time of event: 2023 Sep 28, 03:51 - 2023 Sep 28, 03:59 * geocentric midpoint of event [JD]: 2460215.66331525 * magnitude of target star: 12.59 * magnitude drop [mag]: 1.84 * estimated maximum duration [s]: 5.120 * Moon: 97 % sunlit, 72° distance * Sun: 90° distance * rough path description: SW USA The occultation path -------------------- * approximate projected width [km]: 142 * 1 sigma uncertainty interval [path widths]: +/- 0.01 * 1 sigma uncertainty interval [seconds]: +/- 0.8 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.008, +/- 0.000) * 1 sigma uncertainty ellipse (major, minor, PA): (0.008", 0.000", 90°) * approx speed of asteroid's shadow [km/s]: 17.9007 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4 334-147192 by 431 Nephele on 2023 Sep 28 Centre Star Star Sun Path Limits Error Limits Alt E. Longitude Latitude U.T. Alt Az Alt Limit 1 Limit 2 Limit 3 Limit 4 Crn o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " Latitude Latitude Latitude Latitude 146 0 0 44 38 35 3 51 21.2 0 124 38 43 53 4 .. .. .. 43 52 15 .. .. .. .... 147 0 0 44 9 56 3 51 21.3 1 125 38 43 24 35 44 56 10 43 23 46 44 57 1 -0.53 148 0 0 43 41 25 3 51 21.5 2 125 38 42 56 13 44 27 28 42 55 24 44 28 18 -0.80 149 0 0 43 13 0 3 51 21.9 3 126 38 42 27 58 43 58 53 42 27 9 43 59 44 -0.91 150 0 0 42 44 44 3 51 22.3 4 127 38 41 59 52 43 30 27 41 59 3 43 31 17 -0.97 151 0 0 42 16 38 3 51 23.0 5 127 38 41 31 56 43 2 10 41 31 7 43 3 0 -1.01 152 0 0 41 48 42 3 51 23.7 6 128 38 41 4 10 42 34 3 41 3 22 42 34 53 -1.03 153 0 0 41 20 59 3 51 24.6 6 129 37 40 36 37 42 6 9 40 35 49 42 6 58 -1.05 154 0 0 40 53 28 3 51 25.6 7 130 37 40 9 16 41 38 27 40 8 28 41 39 16 -1.07 155 0 0 40 26 10 3 51 26.7 8 130 37 39 42 9 41 10 59 39 41 21 41 11 48 -1.08 156 0 0 39 59 7 3 51 28.0 9 131 37 39 15 16 40 43 45 39 14 29 40 44 34 -1.09 157 0 0 39 32 20 3 51 29.4 10 132 36 38 48 39 40 16 47 38 47 52 40 17 35 -1.10 158 0 0 39 5 49 3 51 30.9 11 132 36 38 22 18 39 50 5 38 21 31 39 50 53 -1.10 159 0 0 38 39 35 3 51 32.6 12 133 36 37 56 14 39 23 40 37 55 28 39 24 28 -1.11 160 0 0 38 13 39 3 51 34.4 13 134 35 37 30 29 38 57 34 37 29 42 38 58 22 -1.11 161 0 0 37 48 2 3 51 36.4 13 134 35 37 5 2 38 31 46 37 4 16 38 32 34 -1.12 162 0 0 37 22 45 3 51 38.4 14 135 35 36 39 55 38 6 18 36 39 9 38 7 6 -1.12 163 0 0 36 57 49 3 51 40.6 15 136 34 36 15 9 37 41 12 36 14 23 37 41 59 -1.13 164 0 0 36 33 14 3 51 43.0 16 136 34 35 50 44 37 16 26 35 49 58 37 17 13 -1.13 165 0 0 36 9 1 3 51 45.4 17 137 33 35 26 41 36 52 3 35 25 55 36 52 50 -1.13 166 0 0 35 45 11 3 51 48.0 18 138 33 35 3 1 36 28 3 35 2 15 36 28 50 -1.13 167 0 0 35 21 45 3 51 50.8 19 138 32 34 39 44 36 4 26 34 38 59 36 5 13 -1.14 168 0 0 34 58 43 3 51 53.6 19 139 32 34 16 51 35 41 14 34 16 6 35 42 0 -1.14 169 0 0 34 36 5 3 51 56.6 20 140 31 33 54 24 35 18 27 33 53 39 35 19 13 -1.14 170 0 0 34 13 54 3 51 59.7 21 140 31 33 32 21 34 56 5 33 31 36 34 56 52 -1.14 171 0 0 33 52 8 3 52 2.9 22 141 30 33 10 45 34 34 10 33 10 0 34 34 56 -1.15 172 0 0 33 30 49 3 52 6.2 23 142 29 32 49 35 34 12 42 32 48 50 34 13 28 -1.15 173 0 0 33 9 58 3 52 9.7 23 143 29 32 28 53 33 51 42 32 28 8 33 52 28 -1.15 174 0 0 32 49 35 3 52 13.2 24 143 28 32 8 38 33 31 9 32 7 54 33 31 55 -1.15 175 0 0 32 29 40 3 52 16.9 25 144 28 31 48 51 33 11 6 31 48 7 33 11 51 -1.15 176 0 0 32 10 14 3 52 20.7 26 145 27 31 29 34 32 51 31 31 28 50 32 52 16 -1.15 177 0 0 31 51 18 3 52 24.6 26 146 26 31 10 45 32 32 26 31 10 2 32 33 11 -1.16 178 0 0 31 32 51 3 52 28.6 27 147 25 30 52 27 32 13 52 30 51 43 32 14 37 -1.16 179 0 0 31 14 55 3 52 32.7 28 147 25 30 34 38 31 55 47 30 33 55 31 56 32 -1.16 -180 0 0 30 57 30 3 52 36.9 29 148 24 30 17 20 31 38 14 30 16 37 31 38 59 -1.16 -179 0 0 30 40 36 3 52 41.1 29 149 23 30 0 34 31 21 13 29 59 50 31 21 57 -1.16 -178 0 0 30 24 13 3 52 45.5 30 150 22 29 44 18 31 4 43 29 43 35 31 5 27 -1.16 -177 0 1 30 8 23 3 52 50.0 31 151 22 29 28 35 30 48 45 29 27 52 30 49 30 -1.16 -176 0 1 29 53 5 3 52 54.6 31 152 21 29 13 23 30 33 20 29 12 40 30 34 4 -1.17 -175 0 1 29 38 19 3 52 59.2 32 153 20 28 58 44 30 18 28 28 58 1 30 19 12 -1.17 -174 0 1 29 24 7 3 53 3.9 33 154 19 28 44 38 30 4 9 28 43 55 30 4 53 -1.17 -173 0 1 29 10 27 3 53 8.7 33 155 18 28 31 4 29 50 24 28 30 22 29 51 8 -1.17 -172 0 1 28 57 22 3 53 13.6 34 156 18 28 18 4 29 37 13 28 17 22 29 37 56 -1.17 -171 0 1 28 44 50 3 53 18.6 34 157 17 28 5 38 29 24 35 28 4 56 29 25 19 -1.17 -170 0 1 28 32 52 3 53 23.6 35 158 16 27 53 46 29 12 32 27 53 3 29 13 16 -1.17 -169 0 1 28 21 29 3 53 28.7 35 159 15 27 42 27 29 1 4 27 41 45 29 1 47 -1.17 -168 0 1 28 10 40 3 53 33.8 36 160 14 27 31 43 28 50 10 27 31 1 28 50 53 -1.17 -167 0 1 28 0 26 3 53 39.0 36 161 13 27 21 33 28 39 51 27 20 51 28 40 35 -1.17 -166 0 1 27 50 47 3 53 44.3 37 162 13 27 11 59 28 30 8 27 11 17 28 30 51 -1.18 -165 0 1 27 41 43 3 53 49.6 37 163 12 27 2 59 28 21 0 27 2 17 28 21 43 -1.18 -164 0 1 27 33 15 3 53 55.0 38 164 11 26 54 34 28 12 28 26 53 52 28 13 11 -1.18 -163 0 1 27 25 22 3 54 0.4 38 165 10 26 46 44 28 4 31 26 46 2 28 5 14 -1.18 -162 0 1 27 18 4 3 54 5.8 38 166 9 26 39 30 27 57 10 26 38 48 27 57 53 -1.18 -161 0 1 27 11 23 3 54 11.3 39 167 8 26 32 51 27 50 25 26 32 9 27 51 8 -1.18 -160 0 1 27 5 17 3 54 16.8 39 169 7 26 26 48 27 44 17 26 26 6 27 44 59 -1.18 -159 0 1 26 59 47 3 54 22.4 39 170 6 26 21 20 27 38 44 26 20 38 27 39 27 -1.18 -158 0 1 26 54 53 3 54 28.0 39 171 5 26 16 28 27 33 48 26 15 47 27 34 31 -1.18 -157 0 1 26 50 35 3 54 33.6 40 172 5 26 12 12 27 29 28 26 11 31 27 30 11 -1.18 -156 0 1 26 46 53 3 54 39.2 40 173 4 26 8 32 27 25 45 26 7 51 27 26 28 -1.18 -155 0 1 26 43 48 3 54 44.9 40 175 3 26 5 28 27 22 38 26 4 47 27 23 21 -1.18 -154 0 1 26 41 19 3 54 50.6 40 176 2 26 3 1 27 20 8 26 2 19 27 20 51 -1.18 -153 0 1 26 39 27 3 54 56.2 40 177 1 26 1 9 27 18 15 26 0 27 27 18 57 -1.18 -152 0 1 26 38 10 3 55 1.9 40 178 0 25 59 53 27 16 58 25 59 12 27 17 41 -1.18 -151 0 1 26 37 31 3 55 7.6 40 179 -1 25 59 14 27 16 18 25 58 32 27 17 1 -1.18 -150 0 1 26 37 27 3 55 13.3 40 181 -2 25 59 10 27 16 15 25 58 29 27 16 57 -1.18 -149 0 1 26 38 0 3 55 19.0 40 182 -3 25 59 43 27 16 48 25 59 2 27 17 30 -1.19 -148 0 1 26 39 10 3 55 24.7 40 183 -4 26 0 52 27 17 58 26 0 11 27 18 40 -1.19 -147 0 1 26 40 56 3 55 30.4 40 184 -5 26 2 37 27 19 45 26 1 56 27 20 27 -1.19 -146 0 1 26 43 18 3 55 36.0 40 186 -5 26 4 58 27 22 8 26 4 17 27 22 50 -1.19 -145 0 1 26 46 16 3 55 41.7 40 187 -6 26 7 56 27 25 8 26 7 14 27 25 50 -1.19 -144 0 1 26 49 51 3 55 47.3 40 188 -7 26 11 29 27 28 44 26 10 48 27 29 27 -1.19 -143 0 1 26 54 2 3 55 52.9 39 189 -8 26 15 38 27 32 57 26 14 57 27 33 40 -1.19 -142 0 1 26 58 50 3 55 58.5 39 190 -9 26 20 23 27 37 47 26 19 42 27 38 29 -1.19 -141 0 1 27 4 13 3 56 4.1 39 192 -10 26 25 44 27 43 12 26 25 3 27 43 55 -1.19 -140 0 1 27 10 12 3 56 9.6 39 193 -11 26 31 41 27 49 14 26 30 59 27 49 57 -1.19 -139 0 1 27 16 47 3 56 15.1 38 194 -12 26 38 13 27 55 52 26 37 32 27 56 35 -1.19 -138 0 1 27 23 58 3 56 20.5 38 195 -13 26 45 21 28 3 7 26 44 39 28 3 49 -1.19 -137 0 1 27 31 45 3 56 26.0 38 196 -14 26 53 4 28 10 57 26 52 22 28 11 39 -1.19 -136 0 1 27 40 7 3 56 31.3 37 197 -15 27 1 22 28 19 22 27 0 41 28 20 5 -1.19 -135 0 1 27 49 4 3 56 36.6 37 198 -15 27 10 16 28 28 24 27 9 34 28 29 7 -1.19 -134 0 1 27 58 36 3 56 41.9 36 199 -16 27 19 44 28 38 0 27 19 2 28 38 44 -1.19 -133 0 1 28 8 44 3 56 47.1 36 200 -17 27 29 47 28 48 12 27 29 5 28 48 56 -1.19 -132 0 1 28 19 26 3 56 52.2 35 201 -18 27 40 25 28 59 0 27 39 43 28 59 43 -1.19 -131 0 1 28 30 43 3 56 57.3 35 202 -19 27 51 37 29 10 21 27 50 55 29 11 5 -1.19 -130 0 1 28 42 34 3 57 2.4 34 204 -20 28 3 23 29 22 18 28 2 41 29 23 2 -1.19 -129 0 1 28 54 59 3 57 7.3 34 204 -21 28 15 43 29 34 49 28 15 1 29 35 33 -1.19 -128 0 1 29 7 59 3 57 12.2 33 205 -21 28 28 37 29 47 54 28 27 54 29 48 38 -1.19 -127 0 1 29 21 31 3 57 17.0 33 206 -22 28 42 4 30 1 33 28 41 21 30 2 17 -1.19 -126 0 1 29 35 38 3 57 21.7 32 207 -23 28 56 4 30 15 45 28 55 21 30 16 29 -1.19 -125 0 1 29 50 17 3 57 26.4 31 208 -24 29 10 37 30 30 31 29 9 54 30 31 15 -1.19 -124 0 1 30 5 29 3 57 30.9 31 209 -25 29 25 42 30 45 50 29 24 59 30 46 34 -1.19 -123 0 1 30 21 13 3 57 35.4 30 210 -26 29 41 19 31 1 41 29 40 36 31 2 26 -1.19 -122 0 1 30 37 29 3 57 39.8 29 211 -26 29 57 29 31 18 5 29 56 46 31 18 50 -1.19 -121 0 1 30 54 17 3 57 44.1 29 212 -27 30 14 10 31 35 1 30 13 26 31 35 45 -1.19 -120 0 1 31 11 37 3 57 48.3 28 213 -28 30 31 22 31 52 28 30 30 38 31 53 12 -1.19 -119 0 1 31 29 27 3 57 52.4 27 213 -29 30 49 4 32 10 26 30 48 21 32 11 11 -1.19 -118 0 1 31 47 48 3 57 56.4 26 214 -29 31 7 17 32 28 55 31 6 33 32 29 40 -1.19 -117 0 1 32 6 38 3 58 0.2 26 215 -30 31 26 0 32 47 54 31 25 16 32 48 39 -1.19 -116 0 1 32 25 58 3 58 4.0 25 216 -31 31 45 11 33 7 22 31 44 27 33 8 8 -1.19 -115 0 1 32 45 48 3 58 7.7 24 217 -31 32 4 53 33 27 21 32 4 8 33 28 6 -1.19 -114 0 1 33 6 6 3 58 11.3 23 217 -32 32 25 2 33 47 47 32 24 17 33 48 33 -1.19 -113 0 1 33 26 51 3 58 14.7 23 218 -33 32 45 39 34 8 42 32 44 54 34 9 28 -1.19 -112 0 1 33 48 5 3 58 18.1 22 219 -33 33 6 43 34 30 5 33 5 59 34 30 51 -1.19 -111 0 1 34 9 45 3 58 21.3 21 220 -34 33 28 14 34 51 55 33 27 30 34 52 41 -1.19 -110 0 1 34 31 52 3 58 24.4 20 220 -35 33 50 12 35 14 11 33 49 27 35 14 57 -1.19 -109 0 1 34 54 24 3 58 27.3 19 221 -35 34 12 35 35 36 53 34 11 49 35 37 40 -1.19 -108 0 1 35 17 21 3 58 30.2 19 222 -36 34 35 22 36 0 1 34 34 37 36 0 47 -1.19 -107 0 1 35 40 43 3 58 32.9 18 222 -36 34 58 35 36 23 32 34 57 49 36 24 19 -1.19 -106 0 1 36 4 28 3 58 35.5 17 223 -37 35 22 10 36 47 28 35 21 25 36 48 15 -1.19 -105 0 1 36 28 37 3 58 38.0 16 224 -37 35 46 9 37 11 47 35 45 23 37 12 34 -1.19 -104 0 1 36 53 8 3 58 40.3 15 224 -38 36 10 30 37 36 28 36 9 44 37 37 16 -1.19 -103 0 1 37 18 0 3 58 42.5 14 225 -38 36 35 12 38 1 31 36 34 26 38 2 19 -1.19 -102 0 1 37 43 13 3 58 44.6 13 226 -39 37 0 15 38 26 55 36 59 29 38 27 43 -1.19 -101 0 1 38 8 46 3 58 46.6 13 227 -39 37 25 38 38 52 39 37 24 51 38 53 27 -1.19 -100 0 1 38 34 38 3 58 48.4 12 227 -40 37 51 20 39 18 41 37 50 33 39 19 30 -1.20 - 99 0 1 39 0 49 3 58 50.0 11 228 -40 38 17 20 39 45 3 38 16 33 39 45 51 -1.20 - 98 0 1 39 27 16 3 58 51.6 10 229 -40 38 43 38 40 11 41 38 42 50 40 12 30 -1.20 - 97 0 1 39 54 1 3 58 53.0 9 229 -41 39 10 12 40 38 37 39 9 24 40 39 25 -1.20 - 96 0 1 40 21 1 3 58 54.3 8 230 -41 39 37 1 41 5 47 39 36 14 41 6 37 -1.20 - 95 0 1 40 48 16 3 58 55.4 7 231 -41 40 4 6 41 33 13 40 3 18 41 34 2 -1.21 - 94 0 1 41 15 44 3 58 56.4 6 231 -41 40 31 24 42 0 52 40 30 36 42 1 42 -1.21 - 93 0 1 41 43 26 3 58 57.3 6 232 -41 40 58 55 42 28 45 40 58 7 42 29 34 -1.22 - 92 0 1 42 11 19 3 58 58.0 5 233 -42 41 26 39 42 56 48 41 25 50 42 57 38 -1.23 - 91 0 1 42 39 23 3 58 58.6 4 233 -42 41 54 33 43 25 3 41 53 44 43 25 53 -1.24 - 90 0 1 43 7 37 3 58 59.1 3 234 -42 42 22 37 43 53 28 42 21 48 43 54 18 -1.26 - 89 0 1 43 36 0 3 58 59.5 2 235 -42 42 50 50 44 22 1 42 50 1 44 22 52 -1.29 - 88 0 1 44 4 31 3 58 59.7 1 235 -42 43 19 11 44 50 42 43 18 22 44 51 33 -1.38 - 87 0 1 44 33 8 3 58 59.8 0 236 -42 43 47 39 .. .. .. 43 46 50 .. .. .. -1.91 Uncertainty in time = +/- 1 secs Prediction of 2023 Sep 10.7 Data for the target star ------------------------ * name: UCAC4 334-147192 * constellation : Sagittarius * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 18 18 17.5425 DE: -23 20 08.554 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 18 18 17.5425 DE: -23 20 08.554 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.200,0.100) * V mag [mag]: 12.6 * B mag [mag]: 13.4 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (431) Nephele asteroid class: approx. diameter [km]: 92 approx. diameter ["]: 0.051 distance from Earth [AU]: 2.49850 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#78 date of fit: 2023 Aug 23 source of used astrometry: MPC, JPL number of used observations: 0 number of rejected observations: 0 time covered by the observations: 1800 Jan 01 - 1800 Jan 01 1 sigma uncertainty ellipse (major, minor, PA): 0.008", 0.000", 90.2° remarks: * orbital elements for (431)Nephele : Mean anomaly = 332.5012756083 deg Arg. of pericenter = 217.4402265536 deg Long. of node = 117.1822288356 deg Inclination = 1.8279500096 deg Eccentricity = 0.1705163019 Semimajor axis = 3.1376424365 AU Perihelion dist = 2.6026232517 AU Mag: H = 9.13, G = 0.15 Epoch of elements : MJD 60215.16329921 TDT (2023 Sep 28.1633) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#782023Aug23,5.12,2023,9,28,3.919566,0.000513,0.763249,10.103630,-0.009303,0.005647,0.000195,0.000000,0.000000 -150.5369,-23.3273,118.92,-1.90,False UCAC4 334-147192,18.30487295,-23.3357093,13.39,12.59,12.16,0.0,0,,18.32878140,-23.3272892,1.84,1.83,0,0,0 431,Nephele,14.21,91.565,2.4985,0,0,2.582,-0.03,,4.6,0 0,332.4723,2023,9,28,217.4402,117.1822,1.8280,0.17052,3.13764,2.60262,9.02,5.0,0.15 1.009,0.0083,0.0005,90,0.0083,Known errors,0.85,0,-1,-1 20230928_147192,60197.68 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2023 Sep 10, 16:12 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org