IOTA/IOTA-ES occultation update for (551) Ortrud / UCAC4 336-186030 event on 2020 Oct 06, 19:01 UT Visible from Europe Summary ------- On 2020 Oct 06 UT, the 81.5 km diameter asteroid (551) Ortrud will occult a 11.9 mag star in the constellation Sagittarius for observers along a path across Europe. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.52 mag to 15.40 mag (the magnitude of the asteroid) for at most 5.8 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Hugh Harris, astrometry for the asteroid kindly provided by Bill Owen, 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: 2020 Oct 06, 18:58 - 2020 Oct 06, 19:05 * geocentric midpoint of event [JD]: 2459129.29292083 * magnitude of target star: 11.92 * magnitude drop [mag]: 3.52 * estimated maximum duration [s]: 5.8 * Moon: 79 % sunlit, 142° distance * Sun: 92° distance * rough path description: Europe The occultation path -------------------- * approximate projected width [km]: 183 * 1 sigma uncertainty interval [path widths]: +/- 0.29 * 1 sigma uncertainty interval [seconds]: +/- 2.8 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.018, +/- 0.011) * 1 sigma uncertainty ellipse (major, minor, PA): (0.018", 0.011", 83°) * approx speed of asteroid's shadow [km/s]: 14.0849 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4 336-186030 by 551 Ortrud on 2020 Oct 6 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 ' " Longitude Longitude Longitude Longitude 25 53 50 61 0 0 19 5 8.2 0 217 -25 ... .. .. 23 45 44 ... .. .. 22 29 32 .... 24 20 49 60 0 0 19 5 7.9 1 215 -25 26 24 15 22 14 35 ... .. .. 20 59 27 -0.85 22 46 37 59 0 0 19 5 7.1 3 214 -25 24 48 25 20 41 55 25 58 20 19 27 37 -1.39 21 11 0 58 0 0 19 5 5.8 4 213 -25 23 11 29 19 7 31 24 20 36 17 53 51 -1.59 19 33 45 57 0 0 19 5 4.0 5 211 -25 21 33 15 17 31 7 22 41 43 16 17 53 -1.69 17 54 37 56 0 0 19 5 1.5 7 210 -25 19 53 26 15 52 29 21 1 26 14 39 27 -1.75 16 13 19 55 0 0 19 4 58.4 8 208 -24 18 11 47 14 11 19 19 19 31 12 58 15 -1.79 14 29 31 54 0 0 19 4 54.6 9 207 -24 16 28 0 12 27 16 17 35 38 11 13 55 -1.82 12 42 51 53 0 0 19 4 50.1 11 205 -23 14 41 44 10 39 54 15 49 30 9 26 0 -1.84 10 52 54 52 0 0 19 4 44.8 12 204 -23 12 52 37 8 48 47 14 0 44 7 33 59 -1.86 8 59 9 51 0 0 19 4 38.6 13 202 -22 11 0 11 6 53 17 12 8 54 5 37 14 -1.88 7 1 0 50 0 0 19 4 31.6 15 200 -21 9 3 54 4 52 42 10 13 31 3 34 56 -1.89 4 57 39 49 0 0 19 4 23.6 16 199 -20 7 3 8 2 46 7 8 13 58 1 26 2 -1.91 Latitude Latitude Latitude Latitude 3 0 0 48 5 21 19 4 15.3 18 197 -19 47 6 48 49 6 26 46 33 40 49 43 25 -1.92 2 0 0 47 38 29 19 4 10.8 18 196 -18 46 40 30 48 38 55 46 7 39 49 15 29 -1.96 1 0 0 47 12 18 19 4 6.2 19 195 -18 46 14 51 48 12 7 45 42 18 48 48 17 -1.96 0 0 0 46 46 48 19 4 1.5 19 194 -17 45 49 53 47 46 3 45 17 36 48 21 50 -1.97 - 1 0 0 46 22 1 19 3 56.6 20 193 -16 45 25 35 47 20 41 44 53 34 47 56 7 -1.97 - 2 0 0 45 57 56 19 3 51.6 20 192 -16 45 1 59 46 56 4 44 30 13 47 31 9 -1.97 - 3 0 0 45 34 34 19 3 46.5 21 191 -15 44 39 4 46 32 12 44 7 33 47 6 57 -1.98 - 4 0 0 45 11 55 19 3 41.2 21 190 -14 44 16 52 46 9 4 43 45 35 46 43 30 -1.98 - 5 0 0 44 50 0 19 3 35.9 22 189 -14 43 55 22 45 46 40 43 24 19 46 20 49 -1.98 - 6 0 0 44 28 49 19 3 30.4 22 188 -13 43 34 35 45 25 3 43 3 45 45 58 54 -1.99 - 7 0 0 44 8 23 19 3 24.9 23 187 -12 43 14 31 45 4 10 42 43 54 45 37 45 -1.99 - 8 0 0 43 48 41 19 3 19.3 23 186 -12 42 55 11 44 44 4 42 24 45 45 17 23 -1.99 - 9 0 0 43 29 43 19 3 13.5 24 185 -11 42 36 35 44 24 44 42 6 20 44 57 48 -1.99 - 10 0 0 43 11 31 19 3 7.7 24 184 -10 42 18 43 44 6 10 41 48 39 44 39 0 -2.00 - 11 0 0 42 54 5 19 3 1.9 24 183 -9 42 1 35 43 48 22 41 31 42 44 20 59 -2.00 - 12 0 0 42 37 24 19 2 55.9 25 182 -9 41 45 12 43 31 21 41 15 28 44 3 46 -2.00 - 13 0 0 42 21 29 19 2 49.9 25 181 -8 41 29 34 43 15 8 40 59 59 43 47 20 -2.00 - 14 0 0 42 6 20 19 2 43.9 25 180 -7 41 14 41 42 59 41 40 45 15 43 31 42 -2.01 - 15 0 0 41 51 56 19 2 37.8 25 179 -6 41 0 33 42 45 1 40 31 15 43 16 51 -2.01 - 16 0 0 41 38 20 19 2 31.6 26 178 -6 40 47 10 42 31 8 40 18 0 43 2 49 -2.01 - 17 0 0 41 25 29 19 2 25.5 26 177 -5 40 34 33 42 18 3 40 5 31 42 49 34 -2.01 - 18 0 0 41 13 25 19 2 19.2 26 176 -4 40 22 42 42 5 45 39 53 46 42 37 8 -2.01 - 19 0 0 41 2 8 19 2 13.0 26 175 -3 40 11 36 41 54 15 39 42 47 42 25 30 -2.02 - 20 0 0 40 51 38 19 2 6.8 26 174 -2 40 1 17 41 43 33 39 32 33 42 14 40 -2.02 - 21 0 0 40 41 54 19 2 0.5 26 173 -2 39 51 43 41 33 38 39 23 5 42 4 38 -2.02 - 22 0 0 40 32 57 19 1 54.2 26 172 -1 39 42 56 41 24 31 39 14 22 41 55 25 -2.02 - 23 0 0 40 24 47 19 1 48.0 26 170 0 39 34 54 41 16 12 39 6 25 41 47 0 -2.02 - 24 0 0 40 17 24 19 1 41.7 26 169 1 39 27 39 41 8 41 38 59 14 41 39 24 -2.02 - 25 0 0 40 10 49 19 1 35.4 26 168 1 39 21 10 41 1 58 38 52 49 41 32 36 -2.02 - 26 0 0 40 5 0 19 1 29.2 26 167 2 39 15 27 40 56 3 38 47 10 41 26 37 -2.02 - 27 0 0 39 59 58 19 1 23.0 26 166 3 39 10 31 40 50 55 38 42 16 41 21 26 -2.03 - 28 0 0 39 55 44 19 1 16.8 26 165 4 39 6 21 40 46 36 38 38 8 41 17 3 -2.03 - 29 0 0 39 52 16 19 1 10.7 26 164 5 39 2 57 40 43 5 38 34 47 41 13 29 -2.03 - 30 0 0 39 49 36 19 1 4.5 26 163 5 39 0 20 40 40 21 38 32 11 41 10 44 -2.03 - 31 0 0 39 47 43 19 0 58.5 25 162 6 38 58 29 40 38 26 38 30 21 41 8 47 -2.03 - 32 0 0 39 46 37 19 0 52.5 25 161 7 38 57 24 40 37 18 38 29 17 41 7 38 -2.03 - 33 0 0 39 46 18 19 0 46.5 25 160 8 38 57 6 40 36 59 38 28 59 41 7 18 -2.03 - 34 0 0 39 46 46 19 0 40.6 25 159 8 38 57 34 40 37 27 38 29 27 41 7 47 -2.03 - 35 0 0 39 48 1 19 0 34.8 24 158 9 38 58 48 40 38 43 38 30 41 41 9 3 -2.03 - 36 0 0 39 50 3 19 0 29.0 24 157 10 39 0 48 40 40 46 38 32 40 41 11 8 -2.03 - 37 0 0 39 52 52 19 0 23.3 24 156 11 39 3 35 40 43 38 38 35 26 41 14 1 -2.03 - 38 0 0 39 56 28 19 0 17.7 23 155 11 39 7 7 40 47 17 38 38 57 41 17 43 -2.03 - 39 0 0 40 0 50 19 0 12.2 23 154 12 39 11 26 40 51 44 38 43 13 41 22 12 -2.03 - 40 0 0 40 5 59 19 0 6.8 22 153 13 39 16 30 40 56 58 38 48 15 41 27 29 -2.03 - 41 0 0 40 11 55 19 0 1.5 22 152 14 39 22 21 41 3 0 38 54 2 41 33 35 -2.03 - 42 0 0 40 18 38 18 59 56.3 22 152 14 39 28 57 41 9 49 39 0 35 41 40 28 -2.03 - 43 0 0 40 26 6 18 59 51.2 21 151 15 39 36 19 41 17 25 39 7 53 41 48 10 -2.03 - 44 0 0 40 34 21 18 59 46.2 21 150 16 39 44 26 41 25 49 39 15 56 41 56 39 -2.03 - 45 0 0 40 43 23 18 59 41.3 20 149 16 39 53 19 41 35 0 39 24 44 42 5 55 -2.03 - 46 0 0 40 53 10 18 59 36.5 20 148 17 40 2 56 41 44 57 39 34 17 42 15 59 -2.04 - 47 0 0 41 3 43 18 59 31.9 19 147 18 40 13 20 41 55 42 39 44 34 42 26 51 -2.04 - 48 0 0 41 15 2 18 59 27.4 18 146 18 40 24 28 42 7 13 39 55 36 42 38 30 -2.04 - 49 0 0 41 27 7 18 59 23.0 18 145 19 40 36 20 42 19 30 40 7 23 42 50 55 -2.04 - 50 0 0 41 39 57 18 59 18.8 17 145 19 40 48 58 42 32 35 40 19 53 43 4 8 -2.04 - 51 0 0 41 53 32 18 59 14.7 17 144 20 41 2 20 42 46 25 40 33 8 43 18 8 -2.04 - 52 0 0 42 7 53 18 59 10.8 16 143 21 41 16 26 43 1 1 40 47 6 43 32 55 -2.04 - 53 0 0 42 22 58 18 59 7.0 15 142 21 41 31 16 43 16 24 41 1 48 43 48 28 -2.04 - 54 0 0 42 38 48 18 59 3.3 15 141 22 41 46 50 43 32 32 41 17 13 44 4 47 -2.04 - 55 0 0 42 55 23 18 58 59.9 14 141 22 42 3 7 43 49 25 41 33 21 44 21 53 -2.04 - 56 0 0 43 12 42 18 58 56.6 13 140 23 42 20 8 44 7 4 41 50 12 44 39 44 -2.04 - 57 0 0 43 30 45 18 58 53.4 12 139 23 42 37 52 44 25 28 42 7 46 44 58 22 -2.04 - 58 0 0 43 49 31 18 58 50.5 12 138 23 42 56 18 44 44 37 42 26 2 45 17 45 -2.04 - 59 0 0 44 9 1 18 58 47.7 11 137 24 43 15 27 45 4 30 42 44 59 45 37 53 -2.05 - 60 0 0 44 29 14 18 58 45.0 10 137 24 43 35 18 45 25 8 43 4 38 45 58 46 -2.05 - 61 0 0 44 50 10 18 58 42.6 10 136 25 43 55 51 45 46 29 43 24 59 46 20 24 -2.05 - 62 0 0 45 11 49 18 58 40.4 9 135 25 44 17 6 46 8 35 43 46 0 46 42 47 -2.06 - 63 0 0 45 34 9 18 58 38.3 8 134 25 44 39 1 46 31 24 44 7 42 47 5 54 -2.06 - 64 0 0 45 57 11 18 58 36.4 7 134 26 45 1 37 46 54 56 44 30 4 47 29 45 -2.07 - 65 0 0 46 20 55 18 58 34.7 6 133 26 45 24 53 47 19 10 44 53 5 47 54 20 -2.07 - 66 0 0 46 45 20 18 58 33.2 6 132 26 45 48 49 47 44 7 45 16 46 48 19 37 -2.08 - 67 0 0 47 10 25 18 58 31.9 5 131 26 46 13 25 48 9 46 45 41 6 48 45 38 -2.09 - 68 0 0 47 36 10 18 58 30.8 4 131 27 46 38 39 48 36 7 46 6 3 49 12 22 -2.11 - 69 0 0 48 2 35 18 58 29.9 3 130 27 47 4 31 49 3 8 46 31 38 49 39 47 -2.14 - 70 0 0 48 29 39 18 58 29.2 2 129 27 47 31 1 49 30 51 46 57 51 50 7 55 -2.18 - 71 0 0 48 57 22 18 58 28.7 2 128 27 47 58 9 49 59 13 47 24 39 50 36 43 -2.27 - 72 0 0 49 25 42 18 58 28.4 1 128 27 48 25 53 50 28 15 .. .. .. .. .. .. -2.52 - 73 0 0 49 54 40 18 58 28.3 0 127 27 48 54 13 .. .. .. .. .. .. .. .. .. -8.51 Uncertainty in time = +/- 3 secs Prediction of 2020 Aug 15.0 Data for the target star ------------------------ * name: UCAC4 336-186030 * constellation : Sagittarius * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 19 09 08.1856 DE: -22 51 44.110 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 19 09 08.1856 DE: -22 51 44.110 * position source: Gaia DR2 * standard error: RA,DE [mas]: (0.400,0.400) * V mag [mag]: 11.9 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (551) Ortrud asteroid class: approx. diameter [km]: 82 approx. diameter ["]: 0.038 distance from Earth [AU]: 2.97980 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: Preston date of fit: 2020 Aug 15 source of used astrometry: MPC, FASTT, TMO number of used observations: 3286 number of rejected observations: 24 time covered by the observations: 1960 Oct 27 - 2020 Jun 17 1 sigma uncertainty ellipse (major, minor, PA): 0.018", 0.011", 83.2° remarks: * orbital elements for (551)Ortrud : Mean anomaly = 240.05426179 deg Arg. of pericenter = 69.47126037 deg Long. of node = 5.62317698 deg Inclination = 0.39578939 deg Eccentricity = 0.11919375 Semimajor axis = 2.97342523 AU Perihelion dist = 2.61901152 AU Mag: H = 9.57, G = 0.15 Epoch of elements : MJD 59128.79300000 TDT (2020 Oct 06.7930) ------ occelmnt file for Occult BEGIN ----------------------------------- Preston2020Aug15,5.8,2020,10,6,19.0301,-0.12151,0.88646,7.87669,1.07647,0.00578,0.00070,0.00000,0.00000 -13.7547,-22.8286,-108.48,-5.51 UCAC4 336-186030,19.15227379,-22.8622527,0.00,11.92,0.00,0.0,0,,19.17275976,-22.8286496 551,Ortrud,15.40,81.5,2.9798,0,0,1.682,3.18,,4.4 0,239.9018,2020,10,6,69.4713,5.6232,0.3958,0.11919,2.97343,2.61901,9.57,5.0,0.15 1.292,0.0180,0.0110,83,0.0110,Known errors 20201006_186030,59076.00 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2020 Aug 15, 19:41 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org