IOTA/IOTA-ES occultation update for (402) Chloe / UCAC4 387-142778 event on 2023 May 30, 11:05 UT Visible from NW USA, SW Canada Summary ------- On 2023 May 30 UT, the 56.2 km diameter asteroid (402) Chloe will occult a 12.2 mag star in the constellation Aquarius for observers along a path across NW USA, SW Canada. In the case of an occultation, the combined light of the asteroid and the star will drop by 2.05 mag to 14.09 mag (the magnitude of the asteroid) for at most 10.210 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: 99 * date and approx. time of event: 2023 May 30, 10:53 - 2023 May 30, 11:17 * geocentric midpoint of event [JD]: 2460094.96213500 * magnitude of target star: 12.22 * magnitude drop [mag]: 2.05 * estimated maximum duration [s]: 10.210 * Moon: 77 % sunlit, 127° distance * Sun: 111° distance * rough path description: NW USA, SW Canada Additional comments ------------------- twilight The occultation path -------------------- * approximate projected width [km]: 94 * 1 sigma uncertainty interval [path widths]: +/- 0.12 * 1 sigma uncertainty interval [seconds]: +/- 2.2 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.008, +/- 0.004) * 1 sigma uncertainty ellipse (major, minor, PA): (0.008", 0.004", 80°) * approx speed of asteroid's shadow [km/s]: 5.5026 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4 387-142778 by 402 Chloe on 2023 May 30 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 -160 0 0 58 3 5 10 54 1.8 0 115 -10 57 35 34 58 30 56 57 28 56 58 37 45 .... -159 0 0 57 48 28 10 54 2.0 1 116 -10 57 20 56 58 16 20 57 14 18 58 23 9 -0.71 -158 0 0 57 33 42 10 54 2.5 2 117 -11 57 6 10 58 1 35 56 59 31 58 8 24 -0.94 -157 0 0 57 18 48 10 54 3.1 2 117 -11 56 51 15 57 46 41 56 44 36 57 53 31 -1.05 -156 0 0 57 3 45 10 54 3.9 3 118 -11 56 36 12 57 31 39 56 29 33 57 38 29 -1.11 -155 0 0 56 48 35 10 54 5.0 3 119 -11 56 21 1 57 16 29 56 14 22 57 23 19 -1.14 -154 0 0 56 33 16 10 54 6.3 4 120 -11 56 5 42 57 1 11 55 59 3 57 8 1 -1.17 -153 0 0 56 17 50 10 54 7.8 5 121 -12 55 50 16 56 45 45 55 43 37 56 52 35 -1.19 -152 0 0 56 2 18 10 54 9.5 5 122 -12 55 34 43 56 30 12 55 28 3 56 37 2 -1.21 -151 0 0 55 46 37 10 54 11.5 6 122 -12 55 19 2 56 14 32 55 12 23 56 21 23 -1.22 -150 0 0 55 30 51 10 54 13.8 6 123 -12 55 3 16 55 58 46 54 56 36 56 5 36 -1.23 -149 0 0 55 14 58 10 54 16.3 7 124 -12 54 47 23 55 42 52 54 40 44 55 49 43 -1.23 -148 0 0 54 58 59 10 54 19.0 8 125 -12 54 31 24 55 26 53 54 24 45 55 33 43 -1.24 -147 0 0 54 42 54 10 54 22.1 8 126 -12 54 15 19 55 10 48 54 8 40 55 17 38 -1.25 -146 0 0 54 26 44 10 54 25.3 9 127 -12 53 59 10 54 54 38 53 52 31 55 1 28 -1.25 -145 0 0 54 10 29 10 54 28.9 10 128 -12 53 42 55 54 38 22 53 36 17 54 45 12 -1.26 -144 0 0 53 54 9 10 54 32.7 10 128 -12 53 26 36 54 22 2 53 19 58 54 28 52 -1.26 -143 0 0 53 37 46 10 54 36.8 11 129 -13 53 10 13 54 5 38 53 3 35 54 12 28 -1.26 -142 0 0 53 21 18 10 54 41.1 11 130 -13 52 53 47 53 49 10 52 47 8 53 55 59 -1.27 -141 0 0 53 4 47 10 54 45.8 12 131 -13 52 37 16 53 32 38 52 30 38 53 39 27 -1.27 -140 0 0 52 48 14 10 54 50.7 13 132 -13 52 20 43 53 16 3 52 14 5 53 22 52 -1.27 -139 0 0 52 31 37 10 54 55.9 13 133 -13 52 4 8 52 59 26 51 57 30 53 6 15 -1.28 -138 0 0 52 14 58 10 55 1.4 14 134 -13 51 47 30 52 42 46 51 40 53 52 49 35 -1.28 -137 0 0 51 58 18 10 55 7.2 15 134 -13 51 30 51 52 26 5 51 24 14 52 32 53 -1.28 -136 0 0 51 41 37 10 55 13.3 15 135 -13 51 14 11 52 9 22 51 7 34 52 16 10 -1.28 -135 0 0 51 24 54 10 55 19.7 16 136 -13 50 57 30 51 52 39 50 50 53 51 59 26 -1.28 -134 0 0 51 8 12 10 55 26.4 17 137 -12 50 40 48 51 35 55 50 34 12 51 42 42 -1.29 -133 0 0 50 51 29 10 55 33.4 17 138 -12 50 24 7 51 19 11 50 17 31 51 25 57 -1.29 -132 0 0 50 34 47 10 55 40.7 18 139 -12 50 7 27 51 2 27 50 0 51 51 9 14 -1.29 -131 0 0 50 18 7 10 55 48.3 19 140 -12 49 50 48 50 45 45 49 44 12 50 52 31 -1.29 -130 0 0 50 1 28 10 55 56.2 19 141 -12 49 34 10 50 29 4 49 27 35 50 35 50 -1.29 -129 0 0 49 44 51 10 56 4.4 20 142 -12 49 17 35 50 12 26 49 11 0 50 19 11 -1.30 -128 0 0 49 28 16 10 56 12.9 20 142 -12 49 1 2 49 55 49 48 54 28 50 2 34 -1.30 -127 0 0 49 11 45 10 56 21.7 21 143 -12 48 44 33 49 39 16 48 37 59 49 46 0 -1.30 -126 0 0 48 55 17 10 56 30.8 22 144 -11 48 28 7 49 22 47 48 21 33 49 29 30 -1.30 -125 0 0 48 38 54 10 56 40.2 22 145 -11 48 11 45 49 6 21 48 5 12 49 13 5 -1.30 -124 0 0 48 22 35 10 56 49.9 23 146 -11 47 55 28 48 50 1 47 48 56 48 56 43 -1.30 -123 0 0 48 6 22 10 56 59.9 24 147 -11 47 39 17 48 33 45 47 32 45 48 40 28 -1.30 -122 0 0 47 50 14 10 57 10.2 24 148 -11 47 23 11 48 17 36 47 16 40 48 24 17 -1.31 -121 0 0 47 34 12 10 57 20.8 25 149 -10 47 7 12 48 1 32 47 0 40 48 8 13 -1.31 -120 0 0 47 18 18 10 57 31.7 25 150 -10 46 51 19 47 45 35 46 44 48 47 52 16 -1.31 -119 0 0 47 2 31 10 57 42.9 26 151 -10 46 35 34 47 29 46 46 29 4 47 36 26 -1.31 -118 0 0 46 46 51 10 57 54.3 26 152 -9 46 19 56 47 14 4 46 13 27 47 20 43 -1.31 -117 0 0 46 31 20 10 58 6.0 27 153 -9 46 4 27 46 58 30 45 57 58 47 5 9 -1.31 -116 0 0 46 15 58 10 58 18.1 28 154 -9 45 49 7 46 43 6 45 42 39 46 49 44 -1.32 -115 0 0 46 0 45 10 58 30.3 28 155 -8 45 33 57 46 27 51 45 27 29 46 34 29 -1.32 -114 0 0 45 45 42 10 58 42.9 29 156 -8 45 18 56 46 12 46 45 12 29 46 19 23 -1.32 -113 0 0 45 30 50 10 58 55.7 29 157 -8 45 4 6 45 57 51 44 57 39 46 4 28 -1.32 -112 0 0 45 16 8 10 59 8.7 30 158 -7 44 49 27 45 43 7 44 43 1 45 49 44 -1.32 -111 0 0 45 1 39 10 59 22.0 30 160 -7 44 35 0 45 28 35 44 28 34 45 35 11 -1.32 -110 0 0 44 47 21 10 59 35.5 31 161 -7 44 20 44 45 14 15 44 14 19 45 20 50 -1.32 -109 0 0 44 33 16 10 59 49.3 31 162 -6 44 6 41 45 0 8 44 0 16 45 6 42 -1.33 -108 0 0 44 19 24 11 0 3.3 32 163 -6 43 52 51 44 46 13 43 46 27 44 52 47 -1.33 -107 0 0 44 5 45 11 0 17.5 32 164 -5 43 39 15 44 32 32 43 32 51 44 39 5 -1.33 -106 0 0 43 52 20 11 0 32.0 32 165 -5 43 25 53 44 19 5 43 19 29 44 25 38 -1.33 -105 0 0 43 39 10 11 0 46.6 33 166 -4 43 12 45 44 5 52 43 6 22 44 12 24 -1.33 -104 0 0 43 26 15 11 1 1.4 33 168 -4 42 59 52 43 52 55 42 53 29 43 59 26 -1.33 -103 0 0 43 13 35 11 1 16.5 34 169 -3 42 47 14 43 40 12 42 40 52 43 46 43 -1.33 -102 0 0 43 1 10 11 1 31.7 34 170 -3 42 34 52 43 27 46 42 28 31 43 34 16 -1.33 -101 0 0 42 49 2 11 1 47.0 34 171 -2 42 22 46 43 15 36 42 16 26 43 22 5 -1.34 -100 0 0 42 37 11 11 2 2.5 35 172 -2 42 10 57 43 3 42 42 4 37 43 10 11 -1.34 - 99 0 0 42 25 37 11 2 18.2 35 174 -1 41 59 25 42 52 6 41 53 5 42 58 34 -1.34 - 98 0 0 42 14 20 11 2 34.0 35 175 0 41 48 10 42 40 47 41 41 51 42 47 15 -1.34 - 97 0 0 42 3 21 11 2 50.0 35 176 0 41 37 13 42 29 45 41 30 55 42 36 13 -1.34 - 96 0 0 41 52 40 11 3 6.0 36 178 1 41 26 35 42 19 3 41 20 17 42 25 30 -1.34 - 95 0 0 41 42 18 11 3 22.2 36 179 1 41 16 15 42 8 38 41 9 57 42 15 5 -1.34 - 94 0 0 41 32 15 11 3 38.5 36 180 2 41 6 13 41 58 33 40 59 56 42 4 59 -1.34 - 93 0 0 41 22 31 11 3 54.9 36 181 3 40 56 31 41 48 47 40 50 15 41 55 13 -1.35 - 92 0 0 41 13 7 11 4 11.3 36 183 3 40 47 9 41 39 21 40 40 53 41 45 46 -1.35 - 91 0 0 41 4 2 11 4 27.8 36 184 4 40 38 6 41 30 14 40 31 51 41 36 39 -1.35 - 90 0 0 40 55 18 11 4 44.4 36 185 5 40 29 24 41 21 28 40 23 9 41 27 52 -1.35 - 89 0 0 40 46 54 11 5 1.0 36 187 5 40 21 2 41 13 3 40 14 47 41 19 26 -1.35 - 88 0 0 40 38 51 11 5 17.6 36 188 6 40 13 0 41 4 58 40 6 46 41 11 21 -1.35 - 87 0 0 40 31 9 11 5 34.3 36 189 7 40 5 20 40 57 14 39 59 6 41 3 37 -1.35 - 86 0 0 40 23 48 11 5 50.9 36 191 7 39 58 1 40 49 52 39 51 48 40 56 14 -1.35 - 85 0 0 40 16 49 11 6 7.6 36 192 8 39 51 3 40 42 51 39 44 50 40 49 13 -1.35 - 84 0 0 40 10 12 11 6 24.2 36 193 9 39 44 27 40 36 12 39 38 14 40 42 33 -1.35 - 83 0 0 40 3 56 11 6 40.9 36 194 10 39 38 13 40 29 55 39 32 1 40 36 16 -1.35 - 82 0 0 39 58 2 11 6 57.5 36 196 10 39 32 21 40 24 0 39 26 9 40 30 20 -1.36 - 81 0 0 39 52 31 11 7 14.0 36 197 11 39 26 51 40 18 27 39 20 39 40 24 47 -1.36 - 80 0 0 39 47 22 11 7 30.5 36 198 12 39 21 43 40 13 17 39 15 32 40 19 37 -1.36 - 79 0 0 39 42 36 11 7 47.0 36 200 13 39 16 58 40 8 29 39 10 47 40 14 49 -1.36 - 78 0 0 39 38 12 11 8 3.3 35 201 13 39 12 35 40 4 4 39 6 24 40 10 24 -1.36 - 77 0 0 39 34 11 11 8 19.6 35 202 14 39 8 35 40 0 2 39 2 25 40 6 21 -1.36 - 76 0 0 39 30 33 11 8 35.7 35 203 15 39 4 58 39 56 23 38 58 48 40 2 42 -1.36 - 75 0 0 39 27 18 11 8 51.8 35 204 16 39 1 44 39 53 7 38 55 34 39 59 26 -1.36 - 74 0 0 39 24 25 11 9 7.7 34 206 16 38 58 53 39 50 14 38 52 43 39 56 32 -1.36 - 73 0 0 39 21 56 11 9 23.5 34 207 17 38 56 24 39 47 44 38 50 15 39 54 2 -1.36 - 72 0 0 39 19 50 11 9 39.1 34 208 18 38 54 19 39 45 37 38 48 9 39 51 55 -1.36 - 71 0 0 39 18 7 11 9 54.6 33 209 19 38 52 37 39 43 53 38 46 27 39 50 11 -1.36 - 70 0 0 39 16 48 11 10 9.9 33 210 20 38 51 18 39 42 33 38 45 8 39 48 51 -1.36 - 69 0 0 39 15 51 11 10 25.1 33 211 20 38 50 21 39 41 36 38 44 12 39 47 54 -1.36 - 68 0 0 39 15 17 11 10 40.1 32 213 21 38 49 48 39 41 2 38 43 39 39 47 19 -1.36 - 67 0 0 39 15 7 11 10 54.9 32 214 22 38 49 38 39 40 51 38 43 29 39 47 8 -1.36 - 66 0 0 39 15 19 11 11 9.4 31 215 23 38 49 50 39 41 3 38 43 41 39 47 20 -1.36 - 65 0 0 39 15 54 11 11 23.8 31 216 24 38 50 26 39 41 38 38 44 17 39 47 56 -1.36 - 64 0 0 39 16 53 11 11 38.0 30 217 24 38 51 24 39 42 36 38 45 15 39 48 54 -1.36 - 63 0 0 39 18 14 11 11 51.9 30 218 25 38 52 45 39 43 57 38 46 36 39 50 15 -1.36 - 62 0 0 39 19 57 11 12 5.6 29 219 26 38 54 29 39 45 41 38 48 20 39 51 58 -1.36 - 61 0 0 39 22 3 11 12 19.0 29 220 27 38 56 35 39 47 47 38 50 26 39 54 5 -1.36 - 60 0 0 39 24 32 11 12 32.2 28 221 28 38 59 4 39 50 16 38 52 54 39 56 34 -1.36 - 59 0 0 39 27 23 11 12 45.1 27 222 29 39 1 54 39 53 7 38 55 45 39 59 25 -1.36 - 58 0 0 39 30 36 11 12 57.8 27 223 29 39 5 7 39 56 21 38 58 58 40 2 38 -1.36 - 57 0 0 39 34 11 11 13 10.2 26 224 30 39 8 42 39 59 56 39 2 33 40 6 14 -1.36 - 56 0 0 39 38 8 11 13 22.3 26 225 31 39 12 38 40 3 54 39 6 29 40 10 12 -1.36 - 55 0 0 39 42 27 11 13 34.1 25 226 32 39 16 56 40 8 13 39 10 47 40 14 31 -1.36 - 54 0 0 39 47 7 11 13 45.6 24 227 33 39 21 36 40 12 54 39 15 26 40 19 12 -1.36 - 53 0 0 39 52 8 11 13 56.9 24 227 33 39 26 36 40 17 56 39 20 27 40 24 14 -1.36 - 52 0 0 39 57 31 11 14 7.8 23 228 34 39 31 58 40 23 19 39 25 48 40 29 37 -1.36 - 51 0 0 40 3 14 11 14 18.4 22 229 35 39 37 40 40 29 3 39 31 30 40 35 21 -1.36 - 50 0 0 40 9 17 11 14 28.7 22 230 36 39 43 43 40 35 7 39 37 33 40 41 26 -1.36 - 49 0 0 40 15 41 11 14 38.7 21 231 37 39 50 6 40 41 32 39 43 56 40 47 52 -1.36 - 48 0 0 40 22 26 11 14 48.3 20 232 37 39 56 49 40 48 18 39 50 39 40 54 37 -1.36 - 47 0 0 40 29 30 11 14 57.7 20 233 38 40 3 52 40 55 23 39 57 41 41 1 42 -1.36 - 46 0 0 40 36 53 11 15 6.7 19 233 39 40 11 15 41 2 47 40 5 3 41 9 7 -1.36 - 45 0 0 40 44 36 11 15 15.3 18 234 40 40 18 56 41 10 31 40 12 45 41 16 52 -1.35 - 44 0 0 40 52 38 11 15 23.6 18 235 41 40 26 57 41 18 34 40 20 45 41 24 55 -1.36 - 43 0 0 41 0 58 11 15 31.6 17 236 41 40 35 16 41 26 56 40 29 3 41 33 17 -1.36 - 42 0 0 41 9 37 11 15 39.2 16 236 42 40 43 53 41 35 36 40 37 41 41 41 58 -1.36 - 41 0 0 41 18 34 11 15 46.5 15 237 43 40 52 49 41 44 35 40 46 36 41 50 56 -1.36 - 40 0 0 41 27 48 11 15 53.5 15 238 44 41 2 2 41 53 51 40 55 48 42 0 13 -1.36 - 39 0 0 41 37 20 11 16 0.0 14 239 44 41 11 32 42 3 24 41 5 18 42 9 47 -1.36 - 38 0 0 41 47 9 11 16 6.3 13 239 45 41 21 20 42 13 15 41 15 5 42 19 38 -1.36 - 37 0 0 41 57 15 11 16 12.2 12 240 46 41 31 24 42 23 22 41 25 9 42 29 46 -1.36 - 36 0 0 42 7 37 11 16 17.7 12 241 46 41 41 44 42 33 46 41 35 29 42 40 10 -1.36 - 35 0 0 42 18 15 11 16 22.9 11 242 47 41 52 21 42 44 26 41 46 5 42 50 51 -1.36 - 34 0 0 42 29 9 11 16 27.7 10 242 48 42 3 13 42 55 22 41 56 57 43 1 47 -1.36 - 33 0 0 42 40 18 11 16 32.1 9 243 48 42 14 20 43 6 33 42 8 4 43 12 58 -1.36 - 32 0 0 42 51 43 11 16 36.3 9 244 49 42 25 42 43 17 59 42 19 26 43 24 25 -1.37 - 31 0 0 43 3 21 11 16 40.0 8 245 50 42 37 19 43 29 40 42 31 2 43 36 6 -1.37 - 30 0 0 43 15 14 11 16 43.4 7 245 50 42 49 10 43 41 35 42 42 53 43 48 1 -1.37 - 29 0 0 43 27 21 11 16 46.5 6 246 51 43 1 15 43 53 43 42 54 57 44 0 10 -1.38 - 28 0 0 43 39 41 11 16 49.2 6 247 52 43 13 33 44 6 5 43 7 14 44 12 33 -1.38 - 27 0 0 43 52 14 11 16 51.5 5 247 52 43 26 4 44 18 40 43 19 45 44 25 9 -1.39 - 26 0 0 44 4 59 11 16 53.5 4 248 53 43 38 48 44 31 28 43 32 28 44 37 57 -1.41 - 25 0 0 44 17 57 11 16 55.2 3 249 53 43 51 43 44 44 28 43 45 23 44 50 58 -1.42 - 24 0 0 44 31 7 11 16 56.5 3 249 54 44 4 51 44 57 40 43 58 30 45 4 10 -1.45 - 23 0 0 44 44 28 11 16 57.5 2 250 54 44 18 10 45 11 3 44 11 49 45 17 34 -1.50 - 22 0 0 44 58 0 11 16 58.1 1 251 55 44 31 40 45 24 38 44 25 18 45 31 9 -1.61 - 21 0 0 45 11 43 11 16 58.5 0 252 55 44 45 20 45 38 23 44 38 58 45 44 54 -2.14 Uncertainty in time = +/- 2 secs Prediction of 2023 Apr 29.2 Data for the target star ------------------------ * name: UCAC4 387-142778 * constellation : Aquarius * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 21 16 49.6001 DE: -12 44 46.541 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 21 16 49.6003 DE: -12 44 46.540 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.100,0.100) * V mag [mag]: 12.2 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (402) Chloe asteroid class: Barbarian approx. diameter [km]: 56 approx. diameter ["]: 0.034 distance from Earth [AU]: 2.27670 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#106 date of fit: 2023 Apr 24 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", 0.004", 80.428° remarks: * orbital elements for (402)Chloe : Mean anomaly = 144.5005946702 deg Arg. of pericenter = 17.1302875073 deg Long. of node = 129.3315546141 deg Inclination = 11.8333950624 deg Eccentricity = 0.1123491273 Semimajor axis = 2.5580076170 AU Perihelion dist = 2.2706176937 AU Mag: H = 9.05, G = 0.15 Epoch of elements : MJD 60094.46229167 TDT (2023 May 30.4623) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#1062023Apr24,10.21,2023,5,30,11.091240,0.095371,0.796424,3.083497,-0.371866,-0.004921,-0.001673,0.000001,0.000000 -94.5490,-12.6492,13.02,21.77,False UCAC4 387-142778,21.28044445,-12.7462615,0.00,12.22,0.00,0.0,0,,21.30168976,-12.6492098,2.04,0.00,0,0,0 402,Chloe,14.09,56.2,2.2767,0,0,0.814,-1.44,,3.8,0 0,144.3892,2023,5,30,17.1303,129.3316,11.8334,0.11235,2.55801,2.27062,9.07,5.0,0.15 1.121,0.0077,0.0037,80,0.0041,Known errors,-1.00,-1,-1,-1 20230530_142778,60063.19 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2023 Apr 29, 04:32 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org