IOTA/IOTA-ES occultation update for (3171) Wangshouguan / TYC 1974-00030-1 event on 2021 Jan 25, 15:17 UT Visible from N Australia, New Zealand Summary ------- On 2021 Jan 25 UT, the 38.7 km diameter asteroid (3171) Wangshouguan will occult a 10.5 mag star in the constellation Leo Minor for observers along a path across N Australia, New Zealand. In the case of an occultation, the combined light of the asteroid and the star will drop by 5.22 mag to 15.71 mag (the magnitude of the asteroid) for at most 3.3 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: 66 * date and approx. time of event: 2021 Jan 25, 15:10 - 2021 Jan 25, 15:23 * geocentric midpoint of event [JD]: 2459240.13692917 * magnitude of target star: 10.50 * magnitude drop [mag]: 5.22 * estimated maximum duration [s]: 3.3 * Moon: 90 % sunlit, 57° distance * Sun: 155° distance * rough path description: N Australia, New Zealand The occultation path -------------------- * approximate projected width [km]: 55 * 1 sigma uncertainty interval [path widths]: +/- 0.92 * 1 sigma uncertainty interval [seconds]: +/- 5.5 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.039, +/- 0.027) * 1 sigma uncertainty ellipse (major, minor, PA): (0.042", 0.023", 115°) * approx speed of asteroid's shadow [km/s]: 11.6860 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1974-00030-1 by 3171 Wangshouguan on 2021 Jan 25 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 -165 43 42 -57 0 0 15 10 48.1 1 331 0 -165 11 54 -166 15 34 ... .. .. -167 14 6 .... -166 46 21 -56 0 0 15 10 48.4 2 331 -1 -166 15 15 -167 17 29 ... .. .. -168 14 43 0.54 -167 48 14 -55 0 0 15 10 49.0 3 332 -2 -167 17 48 -168 18 43 -166 22 9 -169 14 46 0.74 -168 49 30 -54 0 0 15 10 49.9 4 333 -3 -168 19 41 -169 19 23 -167 25 10 -170 14 19 0.83 -169 50 16 -53 0 0 15 10 51.2 5 334 -4 -169 21 1 -170 19 35 -168 27 31 -171 13 30 0.88 -170 50 38 -52 0 0 15 10 52.7 6 335 -5 -170 21 53 -171 19 26 -169 29 22 -172 12 24 0.91 -171 50 41 -51 0 0 15 10 54.6 8 336 -6 -171 22 25 -172 19 0 -170 30 47 -173 11 6 0.93 -172 50 31 -50 0 0 15 10 56.8 9 336 -8 -172 22 42 -173 18 24 -171 31 52 -174 9 42 0.94 -173 50 13 -49 0 0 15 10 59.4 10 337 -9 -173 22 48 -174 17 42 -172 32 44 -175 8 16 0.96 -174 49 52 -48 0 0 15 11 2.3 11 338 -10 -174 22 50 -175 16 59 -173 33 27 -176 6 52 0.96 -175 49 33 -47 0 0 15 11 5.5 12 339 -11 -175 22 51 -176 16 19 -174 34 6 -177 5 36 0.97 -176 49 20 -46 0 0 15 11 9.1 13 339 -12 -176 22 57 -177 15 48 -175 34 46 -178 4 30 0.98 -177 49 17 -45 0 0 15 11 13.1 15 340 -13 -177 23 10 -178 15 28 -176 35 31 -179 3 40 0.98 -178 49 28 -44 0 0 15 11 17.4 16 341 -15 -178 23 37 -179 15 24 -177 36 26 179 56 51 0.99 -179 49 58 -43 0 0 15 11 22.0 17 342 -16 -179 24 21 179 44 19 -178 37 35 178 56 59 0.99 179 9 9 -42 0 0 15 11 27.0 18 343 -17 179 34 34 178 43 38 -179 39 3 177 56 39 1.00 178 7 49 -41 0 0 15 11 32.4 19 343 -18 178 33 4 177 42 29 179 19 7 176 55 49 1.00 177 5 58 -40 0 0 15 11 38.2 20 344 -20 177 31 4 176 40 47 178 16 51 175 54 22 1.00 176 3 32 -39 0 0 15 11 44.3 22 345 -21 176 28 30 175 38 28 177 14 3 174 52 17 1.00 175 0 27 -38 0 0 15 11 50.9 23 346 -22 175 25 19 174 35 29 176 10 40 173 49 27 1.01 173 56 37 -37 0 0 15 11 57.8 24 347 -23 174 21 25 173 31 44 175 6 37 172 45 50 1.01 172 51 59 -36 0 0 15 12 5.1 25 348 -25 173 16 44 172 27 8 174 1 50 171 41 19 1.01 171 46 28 -35 0 0 15 12 12.8 26 349 -26 172 11 11 171 21 38 172 56 14 170 35 50 1.01 170 39 58 -34 0 0 15 12 20.9 27 350 -27 171 4 41 170 15 8 171 49 43 169 29 19 1.01 169 32 24 -33 0 0 15 12 29.5 29 350 -29 169 57 9 169 7 32 170 42 14 168 21 39 1.01 168 23 41 -32 0 0 15 12 38.5 30 352 -30 168 48 30 167 58 45 169 33 40 167 12 44 1.01 167 13 42 -31 0 0 15 12 47.9 31 353 -31 167 38 36 166 48 41 168 23 55 166 2 28 1.01 166 2 21 -30 0 0 15 12 57.8 32 354 -33 166 27 22 165 37 12 167 12 53 164 50 45 1.01 164 49 30 -29 0 0 15 13 8.1 33 355 -34 165 14 40 164 24 12 166 0 27 163 37 26 1.01 163 35 2 -28 0 0 15 13 19.0 34 356 -36 164 0 23 163 9 32 164 46 29 162 22 23 1.01 162 18 47 -27 0 0 15 13 30.3 35 357 -37 162 44 22 161 53 3 163 30 52 161 5 26 1.01 161 0 37 -26 0 0 15 13 42.1 36 359 -39 161 26 28 160 34 35 162 13 26 159 46 26 1.01 159 40 19 -25 0 0 15 13 54.5 37 0 -40 160 6 29 159 13 58 160 54 1 158 25 10 1.01 158 17 42 -24 0 0 15 14 7.4 38 2 -41 158 44 15 157 50 58 159 32 25 157 1 25 1.01 156 52 32 -23 0 0 15 14 20.9 39 3 -43 157 19 31 156 25 20 158 8 26 155 34 56 1.01 155 24 32 -22 0 0 15 14 35.0 40 5 -44 155 52 1 154 56 49 156 41 49 154 5 24 1.01 153 53 23 -21 0 0 15 14 49.8 41 7 -46 154 21 27 153 25 4 155 12 17 152 32 28 1.01 152 18 44 -20 0 0 15 15 5.3 42 8 -47 152 47 29 151 49 42 153 39 29 150 55 44 1.01 150 40 7 -19 0 0 15 15 21.5 42 10 -49 151 9 40 150 10 16 152 3 3 149 14 42 1.01 148 57 1 -18 0 0 15 15 38.5 43 13 -51 149 27 30 148 26 12 150 22 30 147 28 43 1.01 147 8 46 -17 0 0 15 15 56.4 44 15 -52 147 40 21 146 36 47 148 37 15 145 37 3 1.01 145 14 32 -16 0 0 15 16 15.3 44 17 -54 145 47 26 144 41 10 146 46 37 143 38 42 1.01 143 13 15 -15 0 0 15 16 35.3 44 20 -55 143 47 46 142 38 11 144 49 40 141 32 21 1.01 Latitude Latitude Latitude Latitude 142 0 0 -14 25 36 15 16 47.3 45 21 -56 -14 9 7 -14 42 10 -13 39 9 -15 12 46 1.01 141 0 0 -13 58 27 15 16 57.2 45 23 -57 -13 42 5 -14 14 54 -13 12 18 -14 45 18 1.01 140 0 0 -13 32 13 15 17 7.0 45 24 -57 -13 15 57 -13 48 34 -12 46 22 -14 18 46 1.01 139 0 0 -13 6 54 15 17 16.7 45 25 -58 -12 50 45 -13 23 9 -12 21 20 -13 53 10 1.01 138 0 0 -12 42 30 15 17 26.4 45 26 -58 -12 26 26 -12 58 39 -11 57 12 -13 28 29 1.01 137 0 0 -12 19 1 15 17 36.1 45 27 -59 -12 3 2 -12 35 4 -11 33 58 -13 4 43 1.01 136 0 0 -11 56 26 15 17 45.7 44 29 -59 -11 40 32 -12 12 24 -11 11 37 -12 41 53 1.01 135 0 0 -11 34 45 15 17 55.2 44 30 -60 -11 18 56 -11 50 37 -10 50 10 -12 19 57 1.01 134 0 0 -11 13 57 15 18 4.7 44 31 -60 -10 58 14 -11 29 45 -10 29 36 -11 58 56 1.01 133 0 0 -10 54 4 15 18 14.1 44 32 -60 -10 38 25 -11 9 47 -10 9 55 -11 38 49 1.01 132 0 0 -10 35 4 15 18 23.4 44 33 -61 -10 19 29 -10 50 43 - 9 51 7 -11 19 36 1.01 131 0 0 -10 16 57 15 18 32.7 43 34 -61 -10 1 26 -10 32 32 - 9 33 12 -11 1 18 1.01 130 0 0 - 9 59 43 15 18 41.8 43 35 -61 - 9 44 16 -10 15 14 - 9 16 9 -10 43 53 1.01 129 0 0 - 9 43 22 15 18 50.9 43 36 -61 - 9 27 59 - 9 58 50 - 8 59 58 -10 27 21 1.01 128 0 0 - 9 27 54 15 18 59.9 42 37 -61 - 9 12 34 - 9 43 18 - 8 44 39 -10 11 43 1.01 127 0 0 - 9 13 19 15 19 8.9 42 38 -61 - 8 58 2 - 9 28 39 - 8 30 13 - 9 56 59 1.01 126 0 0 - 8 59 35 15 19 17.7 42 39 -61 - 8 44 22 - 9 14 53 - 8 16 38 - 9 43 7 1.01 125 0 0 - 8 46 45 15 19 26.4 41 40 -61 - 8 31 34 - 9 1 59 - 8 3 55 - 9 30 8 1.01 124 0 0 - 8 34 46 15 19 35.1 41 41 -61 - 8 19 37 - 8 49 58 - 7 52 3 - 9 18 2 1.01 123 0 0 - 8 23 39 15 19 43.6 40 42 -61 - 8 8 33 - 8 38 49 - 7 41 3 - 9 6 48 1.01 122 0 0 - 8 13 24 15 19 52.0 40 43 -61 - 7 58 20 - 8 28 32 - 7 30 54 - 8 56 27 1.01 121 0 0 - 8 4 1 15 20 0.3 39 44 -61 - 7 48 59 - 8 19 7 - 7 21 36 - 8 46 58 1.01 120 0 0 - 7 55 29 15 20 8.5 39 44 -60 - 7 40 29 - 8 10 33 - 7 13 9 - 8 38 21 1.01 119 0 0 - 7 47 49 15 20 16.6 38 45 -60 - 7 32 51 - 8 2 52 - 7 5 34 - 8 30 37 1.01 118 0 0 - 7 41 1 15 20 24.6 37 46 -60 - 7 26 4 - 7 56 2 - 6 58 49 - 8 23 45 1.01 117 0 0 - 7 35 4 15 20 32.5 37 46 -59 - 7 20 8 - 7 50 5 - 6 52 56 - 8 17 45 1.01 116 0 0 - 7 29 59 15 20 40.2 36 47 -59 - 7 15 4 - 7 44 58 - 6 47 53 - 8 12 37 1.01 115 0 0 - 7 25 46 15 20 47.9 35 48 -58 - 7 10 51 - 7 40 44 - 6 43 42 - 8 8 21 1.02 114 0 0 - 7 22 24 15 20 55.4 35 48 -58 - 7 7 30 - 7 37 21 - 6 40 21 - 8 4 58 1.02 113 0 0 - 7 19 53 15 21 2.7 34 49 -57 - 7 4 59 - 7 34 51 - 6 37 51 - 8 2 26 1.02 112 0 0 - 7 18 14 15 21 10.0 33 49 -57 - 7 3 21 - 7 33 11 - 6 36 13 - 8 0 47 1.02 111 0 0 - 7 17 27 15 21 17.1 33 50 -56 - 7 2 33 - 7 32 24 - 6 35 25 - 8 0 0 1.02 110 0 0 - 7 17 31 15 21 24.0 32 51 -56 - 7 2 38 - 7 32 29 - 6 35 29 - 8 0 5 1.02 109 0 0 - 7 18 28 15 21 30.9 31 51 -55 - 7 3 33 - 7 33 26 - 6 36 24 - 8 1 2 1.02 108 0 0 - 7 20 16 15 21 37.5 30 51 -54 - 7 5 21 - 7 35 15 - 6 38 11 - 8 2 53 1.02 107 0 0 - 7 22 56 15 21 44.1 30 52 -54 - 7 8 0 - 7 37 56 - 6 40 49 - 8 5 35 1.02 106 0 0 - 7 26 29 15 21 50.5 29 52 -53 - 7 11 32 - 7 41 29 - 6 44 18 - 8 9 11 1.02 105 0 0 - 7 30 54 15 21 56.7 28 53 -52 - 7 15 56 - 7 45 56 - 6 48 40 - 8 13 40 1.02 104 0 0 - 7 36 11 15 22 2.8 27 53 -51 - 7 21 12 - 7 51 15 - 6 53 53 - 8 19 1 1.03 103 0 0 - 7 42 21 15 22 8.7 26 54 -51 - 7 27 20 - 7 57 26 - 6 59 59 - 8 25 16 1.03 102 0 0 - 7 49 25 15 22 14.5 26 54 -50 - 7 34 22 - 8 4 32 - 7 6 57 - 8 32 25 1.03 101 0 0 - 7 57 21 15 22 20.1 25 54 -49 - 7 42 16 - 8 12 30 - 7 14 47 - 8 40 28 1.03 100 0 0 - 8 6 11 15 22 25.5 24 55 -48 - 7 51 3 - 8 21 22 - 7 23 31 - 8 49 24 1.03 99 0 0 - 8 15 54 15 22 30.7 23 55 -47 - 8 0 45 - 8 31 9 - 7 33 7 - 8 59 15 1.03 98 0 0 - 8 26 32 15 22 35.8 22 55 -46 - 8 11 19 - 8 41 49 - 7 43 37 - 9 10 1 1.03 97 0 0 - 8 38 4 15 22 40.7 21 56 -46 - 8 22 48 - 8 53 24 - 7 55 1 - 9 21 41 1.04 96 0 0 - 8 50 31 15 22 45.5 20 56 -45 - 8 35 12 - 9 5 54 - 8 7 18 - 9 34 17 1.04 95 0 0 - 9 3 52 15 22 50.0 19 56 -44 - 8 48 30 - 9 19 19 - 8 20 30 - 9 47 49 1.04 94 0 0 - 9 18 9 15 22 54.3 18 56 -43 - 9 2 43 - 9 33 39 - 8 34 37 -10 2 16 1.04 93 0 0 - 9 33 21 15 22 58.5 17 57 -42 - 9 17 51 - 9 48 56 - 8 49 38 -10 17 40 1.04 92 0 0 - 9 49 30 15 23 2.4 16 57 -41 - 9 33 56 -10 5 8 - 9 5 35 -10 34 1 1.05 91 0 0 -10 6 35 15 23 6.2 15 57 -40 - 9 50 56 -10 22 18 - 9 22 28 -10 51 19 1.05 90 0 0 -10 24 37 15 23 9.7 14 57 -39 -10 8 53 -10 40 24 - 9 40 16 -11 9 34 1.05 89 0 0 -10 43 36 15 23 13.0 13 58 -38 -10 27 48 -10 59 28 - 9 59 2 -11 28 47 1.05 88 0 0 -11 3 32 15 23 16.1 12 58 -37 -10 47 39 -11 19 30 -10 18 44 -11 48 59 1.06 87 0 0 -11 24 27 15 23 19.0 11 58 -36 -11 8 28 -11 40 31 -10 39 23 -12 10 10 1.06 86 0 0 -11 46 21 15 23 21.7 10 58 -35 -11 30 16 -12 2 30 -11 1 1 -12 32 20 1.06 85 0 0 -12 9 13 15 23 24.1 9 59 -34 -11 53 3 -12 25 28 -11 23 36 -12 55 30 1.07 84 0 0 -12 33 5 15 23 26.3 8 59 -33 -12 16 48 -12 49 27 -11 47 11 -13 19 40 1.07 83 0 0 -12 57 57 15 23 28.2 7 59 -32 -12 41 33 -13 14 25 -12 11 44 -13 44 52 1.08 82 0 0 -13 23 49 15 23 29.9 6 59 -31 -13 7 19 -13 40 25 -12 37 17 -14 11 4 1.09 81 0 0 -13 50 42 15 23 31.3 5 60 -30 -13 34 5 -14 7 25 -13 3 50 -14 38 18 1.10 80 0 0 -14 18 37 15 23 32.5 4 60 -29 -14 1 52 -14 35 27 -13 31 24 -15 6 35 1.12 79 0 0 -14 47 33 15 23 33.4 3 60 -28 -14 30 40 -15 4 32 .. .. .. -15 35 54 1.15 78 0 0 -15 17 32 15 23 34.1 2 60 -27 -15 0 30 -15 34 39 .. .. .. -16 6 17 1.21 77 0 0 -15 48 33 15 23 34.5 1 61 -26 -15 31 23 -16 5 49 .. .. .. -16 37 43 1.43 Uncertainty in time = +/- 6 secs Prediction of 2020 Dec 31.0 Data for the target star ------------------------ * name: TYC 1974-00030-1 * constellation : Leo Minor * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 10 12 16.0432 DE: +28 01 59.966 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 10 12 16.0433 DE: +28 01 59.966 * position source: Gaia EDR3 * standard error: RA,DE [mas]: (0.100,0.100) * V mag [mag]: 10.5 * B mag [mag]: 11.1 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (3171) Wangshouguan asteroid class: approx. diameter [km]: 39 approx. diameter ["]: 0.025 distance from Earth [AU]: 2.12410 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: Preston date of fit: 2020 Nov 29 source of used astrometry: MPC, FASTT, TMO number of used observations: 2440 number of rejected observations: 4 time covered by the observations: 1962 Nov 24 - 2020 Oct 21 1 sigma uncertainty ellipse (major, minor, PA): 0.042", 0.023", 115.2° remarks: * orbital elements for (3171)Wangshouguan : Mean anomaly = 64.98107089 deg Arg. of pericenter = 25.44285199 deg Long. of node = 31.72057955 deg Inclination = 11.41986519 deg Eccentricity = 0.14571262 Semimajor axis = 3.18211500 AU Perihelion dist = 2.71844068 AU Mag: H = 11.10, G = 0.15 Epoch of elements : MJD 59239.63700000 TDT (2021 Jan 25.6370) ------ occelmnt file for Occult BEGIN ----------------------------------- Preston2020Nov29,3.3,2021,1,25,15.2863,-0.32162,-0.63319,-5.88175,2.98515,-0.00239,-0.00071,0.00000,0.00000 158.9237,27.9279,-46.19,-18.80,False TYC 1974-00030-1,10.20445646,28.0333239,11.10,10.50,10.18,0.0,0,,10.22441675,27.9278682 3171,Wangshouguan,15.71,38.7,2.1241,0,0,-1.837,12.35,,2.6 0,64.8705,2021,1,25,25.4429,31.7206,11.4199,0.14571,3.18212,2.71844,11.10,5.0,0.15 1.917,0.0420,0.0230,115,0.0230,Known errors 20210125_0030-1,59214.00 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2020 Dec 31, 00:50 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org