IOTA/IOTA-ES occultation update for (10779) 1991 LW / UCAC4 315-117675 event on 2024 Oct 04, 03:30 UT Visible from Summary ------- On 2024 Oct 04 UT, the 12.6878925926232 km diameter asteroid (10779) 1991 LW will occult a 10.4 mag star in the constellation Ophiuchus for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 8.29 mag to 18.73 mag (the magnitude of the asteroid) for at most 0.470 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: 87 * date and approx. time of event: 2024 Oct 04, 03:28 - 2024 Oct 04, 03:32 * geocentric midpoint of event [JD]: 2460587.64619083 * magnitude of target star: 10.44 * magnitude drop [mag]: 8.29 * estimated maximum duration [s]: 0.470 * Moon: 2 % sunlit, 59° distance * Sun: 75° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 22 * 1 sigma uncertainty interval [path widths]: +/- 0.57 * 1 sigma uncertainty interval [seconds]: +/- 1.2 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.017, +/- 0.006) * 1 sigma uncertainty ellipse (major, minor, PA): (0.018", 0.002", 108°) * approx speed of asteroid's shadow [km/s]: 27.1925 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4 315-117675 by 10779 1991 LW on 2024 Oct 4 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 151 0 0 51 30 0 3 28 15.5 1 138 30 51 21 13 51 38 49 51 11 20 51 48 52 .... 152 0 0 50 49 40 3 28 15.6 1 138 30 50 40 58 50 58 24 50 31 11 51 8 21 -0.75 153 0 0 50 9 29 3 28 15.8 2 139 30 50 0 52 50 18 8 49 51 10 50 27 59 -1.00 154 0 0 49 29 28 3 28 16.1 3 140 31 49 20 57 49 38 3 49 11 20 49 47 48 -1.11 155 0 0 48 49 41 3 28 16.6 4 141 31 48 41 14 48 58 10 48 31 44 49 7 50 -1.17 156 0 0 48 10 10 3 28 17.1 5 142 31 48 1 48 48 18 34 47 52 22 48 28 8 -1.22 157 0 0 47 30 53 3 28 17.7 6 142 31 47 22 36 47 39 13 47 13 16 47 48 41 -1.24 158 0 0 46 51 55 3 28 18.5 7 143 31 46 43 43 47 0 10 46 34 28 47 9 33 -1.26 159 0 0 46 13 17 3 28 19.4 8 144 31 46 5 9 46 21 27 45 56 0 46 30 45 -1.28 160 0 0 45 35 1 3 28 20.3 9 145 31 45 26 58 45 43 6 45 17 53 45 52 18 -1.29 161 0 0 44 57 8 3 28 21.4 10 145 31 44 49 9 45 5 8 44 40 10 45 14 15 -1.30 162 0 0 44 19 39 3 28 22.6 11 146 31 44 11 45 44 27 35 44 2 50 44 36 37 -1.31 163 0 0 43 42 36 3 28 23.9 12 147 31 43 34 46 43 50 28 43 25 57 43 59 24 -1.32 164 0 0 43 6 1 3 28 25.3 13 148 31 42 58 15 43 13 48 42 49 31 43 22 39 -1.33 165 0 0 42 29 54 3 28 26.8 13 148 31 42 22 13 42 37 37 42 13 33 42 46 23 -1.33 166 0 0 41 54 17 3 28 28.4 14 149 31 41 46 40 42 1 56 41 38 5 42 10 38 -1.34 167 0 0 41 19 11 3 28 30.1 15 150 30 41 11 38 41 26 46 41 3 8 41 35 23 -1.34 168 0 0 40 44 38 3 28 31.9 16 151 30 40 37 9 40 52 9 40 28 43 41 0 41 -1.35 169 0 0 40 10 38 3 28 33.9 17 151 30 40 3 12 40 18 4 39 54 51 40 26 32 -1.35 170 0 0 39 37 12 3 28 35.9 18 152 30 39 29 50 39 44 35 39 21 33 39 52 58 -1.35 171 0 0 39 4 21 3 28 38.0 19 153 29 38 57 3 39 11 40 38 48 50 39 19 59 -1.36 172 0 0 38 32 6 3 28 40.2 20 154 29 38 24 52 38 39 22 38 16 43 38 47 37 -1.36 173 0 0 38 0 29 3 28 42.5 20 155 29 37 53 18 38 7 41 37 45 12 38 15 52 -1.36 174 0 0 37 29 29 3 28 44.8 21 155 28 37 22 22 37 36 37 37 14 20 37 44 44 -1.36 175 0 0 36 59 7 3 28 47.3 22 156 28 36 52 4 37 6 13 36 44 6 37 14 16 -1.37 176 0 0 36 29 25 3 28 49.8 23 157 27 36 22 25 36 36 27 36 14 30 36 44 27 -1.37 177 0 0 36 0 23 3 28 52.5 23 158 27 35 53 26 36 7 22 35 45 35 36 15 18 -1.37 178 0 0 35 32 2 3 28 55.2 24 159 26 35 25 7 35 38 58 35 17 20 35 46 50 -1.37 179 0 0 35 4 21 3 28 58.0 25 160 26 34 57 30 35 11 14 34 49 46 35 19 3 -1.37 -180 0 0 34 37 23 3 29 0.8 26 160 25 34 30 34 34 44 13 34 22 53 34 51 58 -1.38 -179 0 0 34 11 6 3 29 3.7 26 161 25 34 4 20 34 17 53 33 56 42 34 25 36 -1.38 -178 0 0 33 45 32 3 29 6.7 27 162 24 33 38 49 33 52 17 33 31 14 33 59 56 -1.38 -177 0 0 33 20 41 3 29 9.8 28 163 23 33 14 1 33 27 23 33 6 29 33 35 0 -1.38 -176 0 0 32 56 34 3 29 12.9 28 164 23 32 49 56 33 3 13 32 42 27 33 10 47 -1.38 -175 0 0 32 33 10 3 29 16.0 29 165 22 32 26 35 32 39 47 32 19 8 32 47 18 -1.39 -174 0 0 32 10 31 3 29 19.3 29 166 21 32 3 58 32 17 6 31 56 34 32 24 34 -1.39 -173 0 0 31 48 36 3 29 22.5 30 167 21 31 42 5 31 55 8 31 34 43 32 2 34 -1.39 -172 0 0 31 27 26 3 29 25.8 31 168 20 31 20 57 31 33 56 31 13 38 31 41 19 -1.39 -171 0 0 31 7 1 3 29 29.2 31 169 19 31 0 34 31 13 29 30 53 17 31 20 50 -1.39 -170 0 0 30 47 21 3 29 32.6 32 170 19 30 40 56 30 53 47 30 33 42 31 1 6 -1.39 -169 0 0 30 28 27 3 29 36.1 32 171 18 30 22 4 30 34 51 30 14 51 30 42 7 -1.39 -168 0 0 30 10 18 3 29 39.6 32 172 17 30 3 57 30 16 41 29 56 47 30 23 55 -1.39 -167 0 0 29 52 56 3 29 43.1 33 173 16 29 46 36 29 59 16 29 39 27 30 6 28 -1.40 -166 0 0 29 36 19 3 29 46.7 33 174 16 29 30 1 29 42 38 29 22 54 29 49 48 -1.40 -165 0 0 29 20 29 3 29 50.2 34 175 15 29 14 12 29 26 46 29 7 7 29 33 55 -1.40 -164 0 0 29 5 25 3 29 53.9 34 176 14 28 59 10 29 11 41 28 52 6 29 18 47 -1.40 -163 0 0 28 51 7 3 29 57.5 34 177 13 28 44 53 28 57 22 28 37 52 29 4 27 -1.40 -162 0 0 28 37 36 3 30 1.2 34 178 12 28 31 24 28 43 49 28 24 24 28 50 53 -1.40 -161 0 0 28 24 52 3 30 4.8 35 179 12 28 18 41 28 31 4 28 11 42 28 38 6 -1.40 -160 0 0 28 12 54 3 30 8.5 35 181 11 28 6 44 28 19 5 27 59 47 28 26 6 -1.40 -159 0 0 28 1 44 3 30 12.2 35 182 10 27 55 35 28 7 53 27 48 38 28 14 53 -1.40 -158 0 0 27 51 20 3 30 15.9 35 183 9 27 45 12 27 57 28 27 38 17 28 4 27 -1.40 -157 0 0 27 41 43 3 30 19.7 35 184 8 27 35 36 27 47 51 27 28 42 27 54 48 -1.40 -156 0 0 27 32 53 3 30 23.4 35 185 7 27 26 47 27 39 0 27 19 54 27 45 56 -1.41 -155 0 0 27 24 50 3 30 27.1 35 186 6 27 18 45 27 30 56 27 11 53 27 37 52 -1.41 -154 0 0 27 17 35 3 30 30.8 35 187 5 27 11 30 27 23 40 27 4 38 27 30 35 -1.41 -153 0 0 27 11 6 3 30 34.6 35 188 5 27 5 2 27 17 11 26 58 11 27 24 5 -1.41 -152 0 0 27 5 24 3 30 38.3 35 189 4 26 59 21 27 11 29 26 52 31 27 18 22 -1.41 -151 0 0 27 0 30 3 30 42.0 35 190 3 26 54 27 27 6 34 26 47 37 27 13 27 -1.41 -150 0 0 26 56 23 3 30 45.7 35 192 2 26 50 20 27 2 26 26 43 31 27 9 18 -1.41 -149 0 0 26 53 3 3 30 49.4 35 193 1 26 47 0 26 59 6 26 40 12 27 5 58 -1.41 -148 0 0 26 50 30 3 30 53.1 35 194 0 26 44 28 26 56 32 26 37 39 27 3 24 -1.41 -147 0 0 26 48 44 3 30 56.7 35 195 -1 26 42 42 26 54 46 26 35 54 27 1 38 -1.41 -146 0 0 26 47 45 3 31 0.3 34 196 -2 26 41 43 26 53 48 26 34 55 27 0 39 -1.41 -145 0 0 26 47 34 3 31 4.0 34 197 -3 26 41 32 26 53 36 26 34 44 27 0 27 -1.41 -144 0 0 26 48 9 3 31 7.5 34 198 -3 26 42 8 26 54 12 26 35 19 27 1 3 -1.41 -143 0 0 26 49 32 3 31 11.1 34 199 -4 26 43 30 26 55 34 26 36 42 27 2 26 -1.41 -142 0 0 26 51 42 3 31 14.6 33 200 -5 26 45 40 26 57 45 26 38 51 27 4 36 -1.41 -141 0 0 26 54 39 3 31 18.1 33 201 -6 26 48 36 27 0 42 26 41 47 27 7 34 -1.41 -140 0 0 26 58 22 3 31 21.6 33 202 -7 26 52 20 27 4 26 26 45 31 27 11 18 -1.41 -139 0 0 27 2 53 3 31 25.0 32 203 -8 26 56 50 27 8 57 26 50 1 27 15 50 -1.41 -138 0 0 27 8 11 3 31 28.4 32 204 -9 27 2 8 27 14 15 26 55 18 27 21 9 -1.41 -137 0 0 27 14 16 3 31 31.7 31 205 -10 27 8 12 27 20 21 27 1 21 27 27 15 -1.41 -136 0 0 27 21 8 3 31 35.0 31 206 -11 27 15 3 27 27 13 27 8 11 27 34 8 -1.41 -135 0 0 27 28 46 3 31 38.3 30 207 -12 27 22 41 27 34 52 27 15 48 27 41 48 -1.41 -134 0 0 27 37 11 3 31 41.5 30 208 -12 27 31 5 27 43 18 27 24 12 27 50 15 -1.41 -133 0 0 27 46 23 3 31 44.7 29 208 -13 27 40 16 27 52 31 27 33 22 27 59 29 -1.42 -132 0 0 27 56 22 3 31 47.8 29 209 -14 27 50 14 28 2 31 27 43 19 28 9 29 -1.42 -131 0 0 28 7 7 3 31 50.8 28 210 -15 28 0 58 28 13 17 27 54 2 28 20 16 -1.42 -130 0 0 28 18 38 3 31 53.8 27 211 -16 28 12 29 28 24 49 28 5 31 28 31 50 -1.42 -129 0 0 28 30 56 3 31 56.7 27 212 -17 28 24 45 28 37 8 28 17 46 28 44 11 -1.42 -128 0 0 28 44 1 3 31 59.6 26 213 -18 28 37 48 28 50 14 28 30 48 28 57 18 -1.42 -127 0 0 28 57 51 3 32 2.4 25 213 -19 28 51 37 29 4 6 28 44 36 29 11 11 -1.42 -126 0 0 29 12 27 3 32 5.1 25 214 -20 29 6 12 29 18 43 28 59 9 29 25 50 -1.42 -125 0 0 29 27 50 3 32 7.8 24 215 -20 29 21 33 29 34 7 29 14 28 29 41 16 -1.42 -124 0 0 29 43 58 3 32 10.4 23 216 -21 29 37 40 29 50 17 29 30 33 29 57 27 -1.42 -123 0 0 30 0 51 3 32 12.9 22 216 -22 29 54 32 30 7 12 29 47 23 30 14 24 -1.42 -122 0 0 30 18 30 3 32 15.4 22 217 -23 30 12 9 30 24 53 30 4 58 30 32 7 -1.42 -121 0 0 30 36 54 3 32 17.7 21 218 -24 30 30 31 30 43 19 30 23 19 30 50 35 -1.42 -120 0 0 30 56 4 3 32 20.0 20 219 -24 30 49 39 31 2 30 30 42 24 31 9 48 -1.42 -119 0 0 31 15 58 3 32 22.2 19 219 -25 31 9 31 31 22 26 31 2 14 31 29 46 -1.42 -118 0 0 31 36 36 3 32 24.3 19 220 -26 31 30 7 31 43 6 31 22 48 31 50 29 -1.42 -117 0 0 31 57 59 3 32 26.4 18 221 -27 31 51 27 32 4 31 31 44 6 32 11 56 -1.42 -116 0 0 32 20 5 3 32 28.3 17 221 -28 32 13 32 32 26 40 32 6 8 32 34 8 -1.42 -115 0 0 32 42 56 3 32 30.2 16 222 -28 32 36 20 32 49 33 32 28 54 32 57 4 -1.42 -114 0 0 33 6 30 3 32 31.9 15 223 -29 32 59 52 33 13 9 32 52 22 33 20 42 -1.42 -113 0 0 33 30 46 3 32 33.6 14 223 -30 33 24 6 33 37 28 33 16 34 33 45 4 -1.43 -112 0 0 33 55 46 3 32 35.2 13 224 -30 33 49 2 34 2 30 33 41 28 34 10 9 -1.43 -111 0 0 34 21 27 3 32 36.7 13 224 -31 34 14 41 34 28 14 34 7 3 34 35 56 -1.43 -110 0 0 34 47 50 3 32 38.0 12 225 -32 34 41 2 34 54 40 34 33 21 35 2 25 -1.43 -109 0 0 35 14 54 3 32 39.3 11 226 -32 35 8 3 35 21 47 35 0 19 35 29 36 -1.43 -108 0 0 35 42 40 3 32 40.5 10 226 -33 35 35 45 35 49 35 35 27 58 35 57 28 -1.44 -107 0 0 36 11 5 3 32 41.6 9 227 -34 36 4 8 36 18 4 35 56 17 36 25 59 -1.44 -106 0 0 36 40 10 3 32 42.5 8 228 -34 36 33 9 36 47 12 36 25 15 36 55 11 -1.44 -105 0 0 37 9 54 3 32 43.4 7 228 -35 37 2 50 37 16 59 36 54 52 37 25 2 -1.45 -104 0 0 37 40 16 3 32 44.2 6 229 -35 37 33 9 37 47 25 37 25 8 37 55 32 -1.46 -103 0 0 38 11 16 3 32 44.8 5 229 -36 38 4 6 38 18 28 37 56 0 38 26 39 -1.47 -102 0 0 38 42 53 3 32 45.3 4 230 -36 38 35 39 38 50 8 38 27 30 38 58 23 -1.48 -101 0 0 39 15 6 3 32 45.8 3 231 -37 39 7 48 39 22 25 38 59 35 39 30 44 -1.51 -100 0 0 39 47 54 3 32 46.1 2 231 -37 39 40 33 39 55 16 39 32 15 40 3 39 -1.55 - 99 0 0 40 21 16 3 32 46.3 1 232 -37 40 13 51 40 28 42 40 5 29 40 37 10 -1.65 - 98 0 0 40 55 11 3 32 46.4 0 233 -38 40 47 43 41 2 42 40 39 17 41 11 14 -2.17 Uncertainty in time = +/- 1 secs Prediction of 2023 Jul 15.6 Data for the target star ------------------------ * name: UCAC4 315-117675 * constellation : Ophiuchus * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 17 40 02.3994 DE: -27 03 20.378 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 17 40 02.3992 DE: -27 03 20.378 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.300,0.200) * V mag [mag]: 10.4 * B mag [mag]: 11.2 * Diameter [mas]: 0.10 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (10779) 1991 LW asteroid class: approx. diameter [km]: 13 approx. diameter ["]: 0.007 distance from Earth [AU]: 2.49710 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#42 date of fit: 2023 Apr 25 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): 0.018", 0.002", 107.624° remarks: * orbital elements for (10779)1991 LW : Mean anomaly = 62.6129416950 deg Arg. of pericenter = 115.5325889734 deg Long. of node = 90.9755551562 deg Inclination = 12.1172436750 deg Eccentricity = 0.1820437079 Semimajor axis = 2.5697000397 AU Perihelion dist = 2.1019023163 AU Mag: H = 13.71, G = 0.15 Epoch of elements : MJD 60587.14619067 TDT (2024 Oct 04.1462) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#422023Apr25,0.47,2024,10,4,3.508580,0.101727,0.807889,15.228489,-1.913381,0.005417,-0.000271,0.000000,0.000000 -160.5545,-27.0701,124.54,-4.51,False UCAC4 315-117675,17.66733321,-27.0556607,11.22,10.44,10.02,0.1,0,,17.69297295,-27.0701301,8.29,8.26,0,0,0 10779,1991 LW,18.73,12.869,2.4971,0,0,4.015,-6.73,,1.0,0 0,62.5780,2024,10,4,115.5326,90.9756,12.1172,0.18204,2.56970,2.10190,13.71,5.0,0.15 1.566,0.0180,0.0024,108,0.0040,Known errors,1.39,0,-1,-1 20241004_117675,60140.61 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2023 Jul 15, 14:36 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org