IOTA/IOTA-ES occultation update for (33074) 1997 WP21 / UCAC4 340-175407 event on 2023 Feb 27, 12:46 UT Visible from W USA Summary ------- On 2023 Feb 27 UT, the 17.6 km diameter asteroid (33074) 1997 WP21 will occult a 12.6 mag star in the constellation Sagittarius for observers along a path across W USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.44 mag to 18.99 mag (the magnitude of the asteroid) for at most 0.560 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: 90 * date and approx. time of event: 2023 Feb 27, 12:43 - 2023 Feb 27, 12:48 * geocentric midpoint of event [JD]: 2460003.03208367 * magnitude of target star: 12.55 * magnitude drop [mag]: 6.44 * estimated maximum duration [s]: 0.560 * Moon: 53 % sunlit, 149° distance * Sun: 56° distance * rough path description: W USA Additional comments ------------------- short duration The occultation path -------------------- * approximate projected width [km]: 25 * 1 sigma uncertainty interval [path widths]: +/- 0.52 * 1 sigma uncertainty interval [seconds]: +/- 1.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.015, +/- 0.004) * 1 sigma uncertainty ellipse (major, minor, PA): (0.015", 0.002", 101°) * approx speed of asteroid's shadow [km/s]: 31.6379 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4 340-175407 by 33074 1997 WP21 on 2023 Feb 27 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 -130 0 0 44 3 37 12 43 52.5 1 122 -29 43 55 35 44 11 41 43 47 14 44 20 6 .... -129 0 0 43 36 57 12 43 52.6 1 123 -28 43 28 56 43 45 0 43 20 36 43 53 24 -0.56 -128 0 0 43 10 18 12 43 52.7 2 123 -28 43 2 18 43 18 20 42 53 59 43 26 43 -0.74 -127 0 0 42 43 40 12 43 52.9 3 124 -27 42 35 40 42 51 40 42 27 23 43 0 2 -0.82 -126 0 0 42 17 3 12 43 53.2 4 125 -26 42 9 5 42 25 3 42 0 48 42 33 24 -0.87 -125 0 0 41 50 30 12 43 53.5 5 126 -26 41 42 33 41 58 28 41 34 17 42 6 48 -0.90 -124 0 0 41 24 0 12 43 53.9 6 126 -25 41 16 4 41 31 57 41 7 50 41 40 16 -0.92 -123 0 0 40 57 35 12 43 54.4 7 127 -24 40 49 40 41 5 31 40 41 27 41 13 48 -0.93 -122 0 0 40 31 15 12 43 54.9 7 128 -24 40 23 21 40 39 10 40 15 9 40 47 26 -0.94 -121 0 0 40 5 1 12 43 55.5 8 128 -23 39 57 9 40 12 55 39 48 58 40 21 10 -0.95 -120 0 0 39 38 55 12 43 56.2 9 129 -22 39 31 4 39 46 48 39 22 55 39 55 1 -0.96 -119 0 0 39 12 57 12 43 57.0 10 129 -22 39 5 7 39 20 49 38 56 59 39 29 1 -0.97 -118 0 0 38 47 8 12 43 57.8 11 130 -21 38 39 19 38 54 58 38 31 13 39 3 9 -0.97 -117 0 0 38 21 29 12 43 58.7 12 131 -20 38 13 41 38 29 17 38 5 36 38 37 27 -0.98 -116 0 0 37 56 0 12 43 59.6 13 131 -19 37 48 14 38 3 47 37 40 10 38 11 55 -0.98 -115 0 0 37 30 42 12 44 0.7 14 132 -19 37 22 58 37 38 28 37 14 55 37 46 35 -0.99 -114 0 0 37 5 37 12 44 1.8 14 133 -18 36 57 54 37 13 22 36 49 53 37 21 27 -0.99 -113 0 0 36 40 45 12 44 3.0 15 133 -17 36 33 3 36 48 28 36 25 3 36 56 32 -0.99 -112 0 0 36 16 7 12 44 4.2 16 134 -16 36 8 26 36 23 49 36 0 28 36 31 51 -1.00 -111 0 0 35 51 43 12 44 5.5 17 135 -15 35 44 4 35 59 23 35 36 7 36 7 24 -1.00 -110 0 0 35 27 35 12 44 6.9 18 136 -15 35 19 57 35 35 14 35 12 1 35 43 13 -1.00 -109 0 0 35 3 42 12 44 8.4 19 136 -14 34 56 6 35 11 20 34 48 11 35 19 18 -1.00 -108 0 0 34 40 7 12 44 9.9 20 137 -13 34 32 31 34 47 43 34 24 39 34 55 39 -1.00 -107 0 0 34 16 48 12 44 11.5 20 138 -12 34 9 15 34 24 23 34 1 23 34 32 18 -1.01 -106 0 0 33 53 49 12 44 13.1 21 138 -11 33 46 16 34 1 22 33 38 26 34 9 16 -1.01 -105 0 0 33 31 8 12 44 14.9 22 139 -10 33 23 37 33 38 40 33 15 48 33 46 32 -1.01 -104 0 0 33 8 46 12 44 16.7 23 140 -10 33 1 16 33 16 17 32 53 29 33 24 8 -1.01 -103 0 0 32 46 45 12 44 18.5 24 140 -9 32 39 16 32 54 14 32 31 31 33 2 3 -1.01 -102 0 0 32 25 4 12 44 20.4 25 141 -8 32 17 37 32 32 32 32 9 53 32 40 20 -1.01 -101 0 0 32 3 45 12 44 22.4 25 142 -7 31 56 20 32 11 12 31 48 37 32 18 58 -1.01 -100 0 0 31 42 48 12 44 24.5 26 143 -6 31 35 24 31 50 13 31 27 42 31 57 58 -1.02 - 99 0 0 31 22 13 12 44 26.6 27 143 -5 31 14 50 31 29 37 31 7 10 31 37 21 -1.02 - 98 0 0 31 2 2 12 44 28.7 28 144 -4 30 54 40 31 9 25 30 47 1 31 17 7 -1.02 - 97 0 0 30 42 14 12 44 30.9 29 145 -3 30 34 53 30 49 35 30 27 16 30 57 16 -1.02 - 96 0 0 30 22 50 12 44 33.2 29 146 -3 30 15 31 30 30 10 30 7 55 30 37 50 -1.02 - 95 0 0 30 3 51 12 44 35.6 30 147 -2 29 56 33 30 11 10 29 48 58 30 18 48 -1.02 - 94 0 0 29 45 16 12 44 37.9 31 147 -1 29 38 0 29 52 34 29 30 26 30 0 11 -1.02 - 93 0 0 29 27 8 12 44 40.4 32 148 0 29 19 52 29 34 24 29 12 20 29 42 0 -1.02 - 92 0 0 29 9 25 12 44 42.9 32 149 1 29 2 11 29 16 40 28 54 39 29 24 15 -1.02 - 91 0 0 28 52 9 12 44 45.4 33 150 2 28 44 55 28 59 23 28 37 25 29 6 56 -1.02 - 90 0 0 28 35 19 12 44 48.0 34 151 3 28 28 7 28 42 32 28 20 38 28 50 4 -1.03 - 89 0 0 28 18 57 12 44 50.7 34 152 4 28 11 46 28 26 9 28 4 18 28 33 40 -1.03 - 88 0 0 28 3 2 12 44 53.3 35 153 5 27 55 52 28 10 13 27 48 25 28 17 43 -1.03 - 87 0 0 27 47 35 12 44 56.1 36 154 6 27 40 26 27 54 45 27 33 1 28 2 14 -1.03 - 86 0 0 27 32 36 12 44 58.8 36 155 7 27 25 28 27 39 45 27 18 4 27 47 13 -1.03 - 85 0 0 27 18 6 12 45 1.6 37 156 8 27 10 59 27 25 14 27 3 36 27 32 41 -1.03 - 84 0 0 27 4 5 12 45 4.5 37 157 9 26 56 59 27 11 12 26 49 36 27 18 37 -1.03 - 83 0 0 26 50 33 12 45 7.4 38 158 10 26 43 28 26 57 39 26 36 6 27 5 3 -1.03 - 82 0 0 26 37 30 12 45 10.3 38 159 10 26 30 26 26 44 35 26 23 5 26 51 59 -1.03 - 81 0 0 26 24 57 12 45 13.2 39 160 11 26 17 54 26 32 1 26 10 34 26 39 24 -1.03 - 80 0 0 26 12 54 12 45 16.2 39 161 12 26 5 52 26 19 58 25 58 33 26 27 20 -1.03 - 79 0 0 26 1 22 12 45 19.2 40 162 13 25 54 20 26 8 24 25 47 2 26 15 45 -1.03 - 78 0 0 25 50 19 12 45 22.3 40 163 14 25 43 18 25 57 21 25 36 1 26 4 41 -1.03 - 77 0 0 25 39 47 12 45 25.3 41 164 15 25 32 47 25 46 49 25 25 31 25 54 8 -1.03 - 76 0 0 25 29 47 12 45 28.4 41 166 16 25 22 47 25 36 47 25 15 31 25 44 6 -1.04 - 75 0 0 25 20 17 12 45 31.6 42 167 17 25 13 18 25 27 16 25 6 3 25 34 34 -1.04 - 74 0 0 25 11 18 12 45 34.7 42 168 18 25 4 19 25 18 17 24 57 5 25 25 34 -1.04 - 73 0 0 25 2 50 12 45 37.9 42 169 19 24 55 53 25 9 49 24 48 39 25 17 5 -1.04 - 72 0 0 24 54 54 12 45 41.0 43 170 20 24 47 57 25 1 52 24 40 44 25 9 8 -1.04 - 71 0 0 24 47 30 12 45 44.2 43 172 21 24 40 33 24 54 27 24 33 20 25 1 43 -1.04 - 70 0 0 24 40 37 12 45 47.4 43 173 21 24 33 41 24 47 34 24 26 29 24 54 49 -1.04 - 69 0 0 24 34 16 12 45 50.7 43 174 22 24 27 20 24 41 12 24 20 8 24 48 27 -1.04 - 68 0 0 24 28 27 12 45 53.9 43 175 23 24 21 32 24 35 23 24 14 20 24 42 37 -1.04 - 67 0 0 24 23 10 12 45 57.1 44 177 24 24 16 15 24 30 6 24 9 4 24 37 19 -1.04 - 66 0 0 24 18 25 12 46 0.4 44 178 25 24 11 31 24 25 20 24 4 20 24 32 34 -1.04 - 65 0 0 24 14 12 12 46 3.6 44 179 26 24 7 18 24 21 8 24 0 8 24 28 21 -1.04 - 64 0 0 24 10 32 12 46 6.9 44 181 27 24 3 38 24 17 27 23 56 28 24 24 40 -1.04 - 63 0 0 24 7 24 12 46 10.1 44 182 28 24 0 30 24 14 19 23 53 20 24 21 31 -1.04 - 62 0 0 24 4 48 12 46 13.4 44 183 29 23 57 55 24 11 43 23 50 45 24 18 55 -1.04 - 61 0 0 24 2 45 12 46 16.7 44 185 29 23 55 52 24 9 39 23 48 42 24 16 52 -1.04 - 60 0 0 24 1 14 12 46 19.9 44 186 30 23 54 21 24 8 8 23 47 12 24 15 21 -1.04 - 59 0 0 24 0 16 12 46 23.2 44 187 31 23 53 23 24 7 10 23 46 13 24 14 22 -1.04 - 58 0 0 23 59 50 12 46 26.4 44 188 32 23 52 57 24 6 44 23 45 48 24 13 56 -1.04 - 57 0 0 23 59 57 12 46 29.7 43 190 33 23 53 3 24 6 51 23 45 54 24 14 3 -1.04 - 56 0 0 24 0 36 12 46 32.9 43 191 33 23 53 42 24 7 30 23 46 33 24 14 42 -1.04 - 55 0 0 24 1 47 12 46 36.1 43 192 34 23 54 54 24 8 41 23 47 44 24 15 53 -1.04 - 54 0 0 24 3 31 12 46 39.3 43 193 35 23 56 38 24 10 25 23 49 28 24 17 37 -1.04 - 53 0 0 24 5 47 12 46 42.5 43 195 36 23 58 54 24 12 42 23 51 44 24 19 54 -1.04 - 52 0 0 24 8 36 12 46 45.7 42 196 37 24 1 42 24 15 31 23 54 32 24 22 43 -1.04 - 51 0 0 24 11 57 12 46 48.8 42 197 37 24 5 3 24 18 52 23 57 53 24 26 5 -1.04 - 50 0 0 24 15 50 12 46 52.0 42 198 38 24 8 56 24 22 45 24 1 46 24 29 59 -1.04 - 49 0 0 24 20 16 12 46 55.1 41 199 39 24 13 21 24 27 11 24 6 10 24 34 25 -1.04 - 48 0 0 24 25 13 12 46 58.2 41 201 40 24 18 18 24 32 9 24 11 7 24 39 23 -1.04 - 47 0 0 24 30 43 12 47 1.2 40 202 40 24 23 48 24 37 39 24 16 36 24 44 53 -1.04 - 46 0 0 24 36 44 12 47 4.3 40 203 41 24 29 49 24 43 41 24 22 37 24 50 56 -1.04 - 45 0 0 24 43 18 12 47 7.3 39 204 42 24 36 22 24 50 15 24 29 9 24 57 30 -1.04 - 44 0 0 24 50 23 12 47 10.2 39 205 42 24 43 26 24 57 20 24 36 13 25 4 36 -1.04 - 43 0 0 24 57 59 12 47 13.2 38 206 43 24 51 2 25 4 57 24 43 49 25 12 14 -1.04 - 42 0 0 25 6 8 12 47 16.1 38 207 43 24 59 10 25 13 6 24 51 56 25 20 23 -1.04 - 41 0 0 25 14 47 12 47 19.0 37 208 44 25 7 49 25 21 46 25 0 34 25 29 4 -1.04 - 40 0 0 25 23 58 12 47 21.8 37 209 45 25 16 59 25 30 57 25 9 43 25 38 16 -1.04 - 39 0 0 25 33 39 12 47 24.6 36 210 45 25 26 40 25 40 40 25 19 24 25 47 58 -1.04 - 38 0 0 25 43 52 12 47 27.4 36 211 46 25 36 51 25 50 53 25 29 35 25 58 12 -1.04 - 37 0 0 25 54 35 12 47 30.1 35 212 46 25 47 33 26 1 36 25 40 16 26 8 57 -1.05 - 36 0 0 26 5 48 12 47 32.8 34 213 47 25 58 46 26 12 51 25 51 28 26 20 12 -1.05 - 35 0 0 26 17 31 12 47 35.4 34 214 47 26 10 29 26 24 35 26 3 10 26 31 57 -1.05 - 34 0 0 26 29 45 12 47 38.0 33 215 47 26 22 41 26 36 49 26 15 22 26 44 12 -1.05 - 33 0 0 26 42 28 12 47 40.6 32 215 48 26 35 24 26 49 33 26 28 3 26 56 57 -1.05 - 32 0 0 26 55 41 12 47 43.1 32 216 48 26 48 36 27 2 47 26 41 14 27 10 11 -1.05 - 31 0 0 27 9 23 12 47 45.5 31 217 49 27 2 16 27 16 30 26 54 54 27 23 55 -1.05 - 30 0 0 27 23 33 12 47 47.9 30 218 49 27 16 26 27 30 41 27 9 3 27 38 8 -1.05 - 29 0 0 27 38 13 12 47 50.3 29 219 49 27 31 5 27 45 22 27 23 40 27 52 49 -1.05 - 28 0 0 27 53 20 12 47 52.6 29 219 49 27 46 11 28 0 30 27 38 45 28 7 59 -1.05 - 27 0 0 28 8 56 12 47 54.8 28 220 50 28 1 46 28 16 7 27 54 19 28 23 37 -1.05 - 26 0 0 28 24 59 12 47 57.0 27 221 50 28 17 48 28 32 11 28 10 20 28 39 42 -1.05 - 25 0 0 28 41 29 12 47 59.1 26 222 50 28 34 17 28 48 43 28 26 48 28 56 15 -1.05 - 24 0 0 28 58 27 12 48 1.1 26 222 50 28 51 13 29 5 41 28 43 43 29 13 14 -1.05 - 23 0 0 29 15 51 12 48 3.1 25 223 50 29 8 36 29 23 6 29 1 5 29 30 41 -1.05 - 22 0 0 29 33 40 12 48 5.1 24 224 50 29 26 25 29 40 57 29 18 52 29 48 33 -1.05 - 21 0 0 29 51 56 12 48 7.0 23 224 50 29 44 39 29 59 14 29 37 5 30 6 51 -1.05 - 20 0 0 30 10 37 12 48 8.8 22 225 50 30 3 19 30 17 56 29 55 43 30 25 34 -1.05 - 19 0 0 30 29 42 12 48 10.5 21 226 50 30 22 23 30 37 2 30 14 46 30 44 42 -1.05 - 18 0 0 30 49 12 12 48 12.2 21 226 50 30 41 51 30 56 33 30 34 14 31 4 14 -1.05 - 17 0 0 31 9 5 12 48 13.8 20 227 50 31 1 43 31 16 28 30 54 4 31 24 10 -1.05 - 16 0 0 31 29 22 12 48 15.3 19 228 50 31 21 59 31 36 46 31 14 19 31 44 30 -1.05 - 15 0 0 31 50 1 12 48 16.8 18 228 50 31 42 37 31 57 27 31 34 55 32 5 12 -1.05 - 14 0 0 32 11 3 12 48 18.2 17 229 49 32 3 37 32 18 30 31 55 54 32 26 16 -1.05 - 13 0 0 32 32 26 12 48 19.6 16 230 49 32 24 59 32 39 54 32 17 15 32 47 42 -1.05 - 12 0 0 32 54 11 12 48 20.8 15 230 49 32 46 42 33 1 40 32 38 56 33 9 29 -1.05 - 11 0 0 33 16 15 12 48 22.0 14 231 48 33 8 46 33 23 46 33 0 58 33 31 37 -1.05 - 10 0 0 33 38 40 12 48 23.2 14 231 48 33 31 9 33 46 12 33 23 20 33 54 4 -1.05 - 9 0 0 34 1 24 12 48 24.2 13 232 48 33 53 51 34 8 57 33 46 1 34 16 51 -1.06 - 8 0 0 34 24 26 12 48 25.2 12 233 47 34 16 52 34 32 1 34 9 1 34 39 56 -1.06 - 7 0 0 34 47 46 12 48 26.1 11 233 47 34 40 11 34 55 22 34 32 18 35 3 19 -1.06 - 6 0 0 35 11 23 12 48 26.9 10 234 47 35 3 46 35 19 1 34 55 52 35 26 59 -1.06 - 5 0 0 35 35 17 12 48 27.7 9 234 46 35 27 39 35 42 56 35 19 43 35 50 55 -1.06 - 4 0 0 35 59 26 12 48 28.4 8 235 46 35 51 46 36 7 6 35 43 49 36 15 7 -1.07 - 3 0 0 36 23 50 12 48 29.0 7 236 45 36 16 9 36 31 32 36 8 11 36 39 34 -1.07 - 2 0 0 36 48 29 12 48 29.5 6 236 45 36 40 47 36 56 12 36 32 47 37 4 16 -1.07 - 1 0 0 37 13 21 12 48 30.0 6 237 44 37 5 37 37 21 5 36 57 36 37 29 10 -1.08 0 0 0 37 38 25 12 48 30.4 5 237 43 37 30 41 37 46 11 37 22 38 37 54 18 -1.09 1 0 0 38 3 42 12 48 30.7 4 238 43 37 55 56 38 11 29 37 47 52 38 19 37 -1.10 2 0 0 38 29 10 12 48 31.0 3 239 42 38 21 22 38 36 58 38 13 17 38 45 8 -1.12 3 0 0 38 54 48 12 48 31.2 2 239 42 38 46 59 39 2 38 38 38 52 39 10 48 -1.16 4 0 0 39 20 35 12 48 31.3 1 240 41 39 12 45 39 28 27 39 4 37 39 36 39 -1.26 5 0 0 39 46 31 12 48 31.3 0 241 40 39 38 40 39 54 24 39 30 31 40 2 37 -2.34 Uncertainty in time = +/- 1 secs Prediction of 2023 Feb 15.9 Data for the target star ------------------------ * name: UCAC4 340-175407 * constellation : Sagittarius * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 18 55 07.5810 DE: -22 08 29.129 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 18 55 07.5810 DE: -22 08 29.129 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.100,0.100) * V mag [mag]: 12.6 * B mag [mag]: 13.3 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (33074) 1997 WP21 asteroid class: approx. diameter [km]: 18 approx. diameter ["]: 0.006 distance from Earth [AU]: 3.88530 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#46 date of fit: 2023 Feb 09 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): 0.015", 0.002", 101.21° remarks: * orbital elements for (33074)1997 WP21 : Mean anomaly = 136.2867955401 deg Arg. of pericenter = 33.8456359427 deg Long. of node = 91.3614463145 deg Inclination = 17.9623784724 deg Eccentricity = 0.1013501365 Semimajor axis = 3.1777985612 AU Perihelion dist = 2.8557282431 AU Mag: H = 12.57, G = 0.15 Epoch of elements : MJD 60002.53207679 TDT (2023 Feb 27.5321) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#462023Feb09,0.56,2023,2,27,12.770008,0.033453,0.719518,17.838920,-0.810548,-0.004943,-0.000443,-0.000001,0.000000 -64.5224,-22.1130,-8.37,-8.32,False UCAC4 340-175407,18.91877247,-22.1414247,13.32,12.55,12.13,0.0,0,,18.94153645,-22.1130263,6.44,6.41,0,0,1 33074,1997 WP21,18.99,17.6,3.8853,0,0,2.906,-1.83,,1.8,0 0,136.1942,2023,2,27,33.8456,91.3614,17.9624,0.10135,3.17780,2.85573,12.58,5.0,0.15 1.521,0.0150,0.0024,101,0.0033,Known errors,-1.00,-1,-1,-1 20230227_175407,59990.86 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2023 Feb 15, 20:41 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org