IOTA/IOTA-ES occultation update for (86) Semele / UCAC4 326-152005 event on 2023 Jul 10, 19:24 UT Visible from SW Asia Summary ------- On 2023 Jul 10 UT, the 116.4 km diameter asteroid (86) Semele will occult a 12.5 mag star in the constellation Sagittarius for observers along a path across SW Asia. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.40 mag to 13.50 mag (the magnitude of the asteroid) for at most 8.770 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 Jul 10, 19:20 - 2023 Jul 10, 19:27 * geocentric midpoint of event [JD]: 2460136.30859500 * magnitude of target star: 12.45 * magnitude drop [mag]: 1.40 * estimated maximum duration [s]: 8.770 * Moon: 42 % sunlit, 112° distance * Sun: 168° distance * rough path description: SW Asia The occultation path -------------------- * approximate projected width [km]: 298 * 1 sigma uncertainty interval [path widths]: +/- 0.11 * 1 sigma uncertainty interval [seconds]: +/- 3.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.026, +/- 0.006) * 1 sigma uncertainty ellipse (major, minor, PA): (0.026", 0.006", 94°) * approx speed of asteroid's shadow [km/s]: 13.2739 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4 326-152005 by 86 Semele on 2023 Jul 10 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 1 0 0 .. .. .... .. .. .. .. .. .. .. .. .. 50 26 2 .. .. .. 50 3 36 .... 2 0 0 51 40 30 19 27 27.8 0 133 4 .. .. .. 49 52 59 .. .. .. 49 30 56 .... 3 0 0 51 6 27 19 27 27.6 1 133 3 .. .. .. 49 20 54 .. .. .. 48 59 12 -0.79 4 0 0 50 33 29 19 27 27.3 2 134 3 52 28 12 48 49 47 52 54 58 48 28 26 -1.59 5 0 0 50 1 36 19 27 26.6 3 135 2 51 53 59 48 19 37 52 20 7 47 58 36 -1.87 6 0 0 49 30 46 19 27 25.7 3 136 1 51 20 59 47 50 25 51 46 33 47 29 42 -2.01 7 0 0 49 0 59 19 27 24.6 4 136 0 50 49 11 47 22 10 51 14 13 47 1 43 -2.09 8 0 0 48 32 13 19 27 23.2 5 137 -1 50 18 33 46 54 50 50 43 6 46 34 40 -2.15 9 0 0 48 4 29 19 27 21.6 6 138 -1 49 49 4 46 28 27 50 13 9 46 8 32 -2.19 10 0 0 47 37 45 19 27 19.8 7 139 -2 49 20 42 46 2 59 49 44 22 45 43 18 -2.22 11 0 0 47 12 0 19 27 17.7 7 139 -3 48 53 26 45 38 26 49 16 42 45 18 59 -2.24 12 0 0 46 47 14 19 27 15.4 8 140 -4 48 27 14 45 14 48 48 50 9 44 55 34 -2.26 13 0 0 46 23 27 19 27 13.0 9 141 -5 48 2 7 44 52 4 48 24 41 44 33 2 -2.28 14 0 0 46 0 37 19 27 10.3 10 142 -5 47 38 2 44 30 14 48 0 17 44 11 23 -2.29 15 0 0 45 38 45 19 27 7.4 10 143 -6 47 14 59 44 9 17 47 36 57 43 50 38 -2.30 16 0 0 45 17 49 19 27 4.3 11 143 -7 46 52 58 43 49 14 47 14 39 43 30 45 -2.31 17 0 0 44 57 49 19 27 1.1 12 144 -8 46 31 57 43 30 4 46 53 23 43 11 45 -2.32 18 0 0 44 38 46 19 26 57.6 12 145 -8 46 11 56 43 11 47 46 33 8 42 53 37 -2.32 19 0 0 44 20 38 19 26 54.0 13 146 -9 45 52 55 42 54 23 46 13 53 42 36 21 -2.33 20 0 0 44 3 25 19 26 50.2 14 146 -10 45 34 52 42 37 51 45 55 38 42 19 57 -2.33 21 0 0 43 47 7 19 26 46.3 14 147 -10 45 17 47 42 22 11 45 38 21 42 4 24 -2.34 22 0 0 43 31 43 19 26 42.2 15 148 -11 45 1 40 42 7 23 45 22 3 41 49 43 -2.34 23 0 0 43 17 13 19 26 38.0 15 149 -12 44 46 30 41 53 26 45 6 44 41 35 53 -2.34 24 0 0 43 3 37 19 26 33.6 16 150 -13 44 32 17 41 40 21 44 52 22 41 22 54 -2.35 25 0 0 42 50 55 19 26 29.1 16 150 -13 44 19 0 41 28 8 44 38 56 41 10 46 -2.35 26 0 0 42 39 6 19 26 24.4 17 151 -14 44 6 39 41 16 45 44 26 28 40 59 28 -2.35 27 0 0 42 28 10 19 26 19.6 17 152 -14 43 55 14 41 6 13 44 14 55 40 49 1 -2.35 28 0 0 42 18 7 19 26 14.7 18 153 -15 43 44 44 40 56 32 44 4 19 40 39 25 -2.36 29 0 0 42 8 56 19 26 9.7 18 154 -16 43 35 10 40 47 42 43 54 39 40 30 38 -2.36 30 0 0 42 0 38 19 26 4.6 19 155 -16 43 26 30 40 39 42 43 45 53 40 22 41 -2.36 31 0 0 41 53 12 19 25 59.4 19 155 -17 43 18 45 40 32 32 43 38 3 40 15 35 -2.36 32 0 0 41 46 38 19 25 54.0 20 156 -17 43 11 54 40 26 12 43 31 9 40 9 18 -2.36 33 0 0 41 40 56 19 25 48.6 20 157 -18 43 5 57 40 20 42 43 25 8 40 3 51 -2.36 34 0 0 41 36 5 19 25 43.1 20 158 -18 43 0 54 40 16 3 43 20 2 39 59 13 -2.37 35 0 0 41 32 7 19 25 37.5 21 159 -19 42 56 45 40 12 13 43 15 51 39 55 25 -2.37 36 0 0 41 29 0 19 25 31.8 21 160 -19 42 53 30 40 9 13 43 12 33 39 52 26 -2.37 37 0 0 41 26 44 19 25 26.1 21 161 -20 42 51 8 40 7 2 43 10 10 39 50 17 -2.37 38 0 0 41 25 20 19 25 20.3 22 162 -20 42 49 40 40 5 41 43 8 41 39 48 57 -2.37 39 0 0 41 24 47 19 25 14.4 22 163 -20 42 49 5 40 5 10 43 8 5 39 48 26 -2.37 40 0 0 41 25 6 19 25 8.5 22 164 -21 42 49 23 40 5 28 43 8 24 39 48 44 -2.37 41 0 0 41 26 15 19 25 2.5 22 165 -21 42 50 35 40 6 36 43 9 35 39 49 52 -2.37 42 0 0 41 28 16 19 24 56.5 22 165 -21 42 52 39 40 8 34 43 11 41 39 51 48 -2.38 43 0 0 41 31 8 19 24 50.4 22 166 -22 42 55 38 40 11 21 43 14 41 39 54 34 -2.38 44 0 0 41 34 51 19 24 44.3 23 167 -22 42 59 30 40 14 57 43 18 36 39 58 9 -2.38 45 0 0 41 39 26 19 24 38.2 23 168 -22 43 4 16 40 19 23 43 23 24 40 2 33 -2.38 46 0 0 41 44 53 19 24 32.1 23 169 -22 43 9 55 40 24 39 43 29 6 40 7 47 -2.38 47 0 0 41 51 10 19 24 25.9 23 170 -23 43 16 28 40 30 44 43 35 43 40 13 50 -2.38 48 0 0 41 58 20 19 24 19.7 23 171 -23 43 23 54 40 37 39 43 43 13 40 20 42 -2.38 49 0 0 42 6 21 19 24 13.6 23 172 -23 43 32 14 40 45 23 43 51 38 40 28 23 -2.39 50 0 0 42 15 13 19 24 7.4 23 173 -23 43 41 28 40 53 58 44 0 57 40 36 54 -2.39 51 0 0 42 24 56 19 24 1.2 23 174 -23 43 51 36 41 3 21 44 11 11 40 46 14 -2.39 52 0 0 42 35 32 19 23 55.1 22 175 -23 44 2 38 41 13 34 44 22 20 40 56 22 -2.39 53 0 0 42 47 0 19 23 48.9 22 176 -23 44 14 35 41 24 38 44 34 24 41 7 21 -2.39 54 0 0 42 59 20 19 23 42.8 22 177 -23 44 27 27 41 36 31 44 47 23 41 19 9 -2.40 55 0 0 43 12 32 19 23 36.7 22 178 -23 44 41 14 41 49 15 45 1 19 41 31 47 -2.40 56 0 0 43 26 37 19 23 30.7 22 179 -23 44 55 56 42 2 49 45 16 10 41 45 15 -2.40 57 0 0 43 41 34 19 23 24.7 22 180 -23 45 11 34 42 17 13 45 31 58 41 59 33 -2.40 58 0 0 43 57 25 19 23 18.7 21 181 -23 45 28 8 42 32 28 45 48 43 42 14 41 -2.40 59 0 0 44 14 9 19 23 12.8 21 182 -23 45 45 38 42 48 34 46 6 25 42 30 40 -2.41 60 0 0 44 31 47 19 23 7.0 21 183 -23 46 4 6 43 5 31 46 25 5 42 47 28 -2.41 61 0 0 44 50 18 19 23 1.2 20 184 -23 46 23 31 43 23 18 46 44 43 43 5 8 -2.41 62 0 0 45 9 43 19 22 55.5 20 185 -22 46 43 53 43 41 58 47 5 20 43 23 38 -2.42 63 0 0 45 30 3 19 22 49.9 20 185 -22 47 5 15 44 1 28 47 26 57 43 42 59 -2.42 64 0 0 45 51 18 19 22 44.4 19 186 -22 47 27 35 44 21 50 47 49 33 44 3 11 -2.42 65 0 0 46 13 28 19 22 39.0 19 187 -22 47 50 55 44 43 5 48 13 11 44 24 14 -2.42 66 0 0 46 36 34 19 22 33.6 18 188 -21 48 15 15 45 5 11 48 37 50 44 46 9 -2.43 67 0 0 47 0 36 19 22 28.4 18 189 -21 48 40 37 45 28 10 49 3 32 45 8 56 -2.43 68 0 0 47 25 34 19 22 23.3 17 190 -20 49 7 0 45 52 1 49 30 18 45 32 35 -2.43 69 0 0 47 51 30 19 22 18.4 17 191 -20 49 34 27 46 16 45 49 58 8 45 57 6 -2.44 70 0 0 48 18 23 19 22 13.5 16 192 -20 50 2 58 46 42 23 50 27 4 46 22 29 -2.44 71 0 0 48 46 15 19 22 8.8 15 193 -19 50 32 35 47 8 55 50 57 8 46 48 45 -2.44 72 0 0 49 15 6 19 22 4.3 15 194 -19 51 3 18 47 36 20 51 28 20 47 15 55 -2.45 73 0 0 49 44 56 19 21 59.9 14 194 -18 51 35 9 48 4 39 52 0 43 47 43 57 -2.45 74 0 0 50 15 48 19 21 55.6 14 195 -18 52 8 9 48 33 54 52 34 18 48 12 53 -2.46 75 0 0 50 47 41 19 21 51.6 13 196 -17 52 42 22 49 4 3 53 9 7 48 42 44 -2.46 76 0 0 51 20 36 19 21 47.7 12 197 -16 53 17 47 49 35 8 53 45 13 49 13 28 -2.47 77 0 0 51 54 35 19 21 44.0 11 198 -16 53 54 28 50 7 9 54 22 39 49 45 8 -2.47 78 0 0 52 29 38 19 21 40.5 11 199 -15 54 32 28 50 40 7 55 1 27 50 17 43 -2.48 79 0 0 53 5 47 19 21 37.3 10 200 -15 55 11 49 51 14 2 55 41 42 50 51 13 -2.49 80 0 0 53 43 4 19 21 34.2 9 200 -14 55 52 35 51 48 54 56 23 27 51 25 40 -2.49 81 0 0 54 21 30 19 21 31.4 8 201 -13 56 34 51 52 24 45 57 6 49 52 1 3 -2.50 82 0 0 55 1 7 19 21 28.8 8 202 -12 57 18 40 53 1 35 57 51 52 52 37 23 -2.51 83 0 0 55 41 58 19 21 26.4 7 203 -12 58 4 10 53 39 25 58 38 46 53 14 42 -2.53 84 0 0 56 24 4 19 21 24.3 6 204 -11 58 51 26 54 18 15 59 27 38 53 52 58 -2.54 85 0 0 57 7 29 19 21 22.5 5 205 -10 59 40 39 54 58 7 60 18 41 54 32 14 -2.57 86 0 0 57 52 15 19 21 21.0 4 206 -9 60 31 59 55 39 2 61 12 10 55 12 30 -2.60 87 0 0 58 38 28 19 21 19.8 3 206 -8 61 25 41 56 21 1 .. .. .. 55 53 47 -2.66 88 0 0 59 26 11 19 21 18.9 2 207 -7 .. .. .. 57 4 6 .. .. .. 56 36 6 -2.76 89 0 0 60 15 31 19 21 18.3 1 208 -6 .. .. .. 57 48 18 .. .. .. 57 19 29 -3.04 90 0 0 61 6 35 19 21 18.1 0 209 -5 .. .. .. 58 33 38 .. .. .. 58 3 56 -5.70 91 0 0 .. .. .... .. .. .. .. .. .. .. .. .. 59 20 10 .. .. .. 58 49 29 .... 92 0 0 .. .. .... .. .. .. .. .. .. .. .. .. 60 7 55 .. .. .. 59 36 10 .... 93 0 0 .. .. .... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 60 24 2 .... Uncertainty in time = +/- 3 secs Prediction of 2023 May 14.2 Data for the target star ------------------------ * name: UCAC4 326-152005 * constellation : Sagittarius * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 18 24 33.3502 DE: -24 55 48.418 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 18 24 33.3502 DE: -24 55 48.418 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.200,0.200) * V mag [mag]: 12.5 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (86) Semele asteroid class: approx. diameter [km]: 116 approx. diameter ["]: 0.071 distance from Earth [AU]: 2.26410 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#119 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): 0.026", 0.006", 93.513° remarks: * orbital elements for (86)Semele : Mean anomaly = 268.2629156741 deg Arg. of pericenter = 308.9879787258 deg Long. of node = 86.0687965331 deg Inclination = 4.8220279409 deg Eccentricity = 0.2163163729 Semimajor axis = 3.1041131434 AU Perihelion dist = 2.4326426471 AU Mag: H = 8.77, G = 0.15 Epoch of elements : MJD 60135.80854167 TDT (2023 Jul 10.8085) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#1192023Apr24,8.77,2023,7,10,19.406280,-0.121938,0.912442,-7.426179,-0.992230,0.001174,0.000209,0.000001,0.000000 56.9510,-24.9177,-109.73,22.19,False UCAC4 326-152005,18.40926396,-24.9301162,0.00,12.45,0.00,0.0,0,,18.43363672,-24.9176695,1.40,0.00,0,0,0 86,Semele,13.50,116.4,2.2641,0,0,-2.120,-3.85,,5.8,0 0,268.1172,2023,7,10,308.9880,86.0688,4.8220,0.21632,3.10411,2.43264,8.80,5.0,0.15 1.109,0.0257,0.0060,94,0.0077,Known errors,-1.00,-1,-1,-1 20230710_152005,60078.17 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2023 May 14, 04:00 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org