IOTA/IOTA-ES occultation update for (267) Tirza / UCAC4 570-032454 event on 2023 Oct 13, 18:32 UT Visible from Australia Summary ------- On 2023 Oct 13 UT, the 53 km diameter asteroid (267) Tirza will occult a 12.1 mag star in the constellation Gemini for observers along a path across Australia. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.78 mag to 15.84 mag (the magnitude of the asteroid) for at most 5.570 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: 100 * date and approx. time of event: 2023 Oct 13, 18:25 - 2023 Oct 13, 18:38 * geocentric midpoint of event [JD]: 2460231.27236558 * magnitude of target star: 12.09 * magnitude drop [mag]: 3.78 * estimated maximum duration [s]: 5.570 * Moon: 1 % sunlit, 89° distance * Sun: 100° distance * rough path description: Australia The occultation path -------------------- * approximate projected width [km]: 99 * 1 sigma uncertainty interval [path widths]: +/- 0.04 * 1 sigma uncertainty interval [seconds]: +/- 1.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.008, +/- 0.000) * 1 sigma uncertainty ellipse (major, minor, PA): (0.008", 0.000", 88°) * approx speed of asteroid's shadow [km/s]: 9.5139 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4 570-032454 by 267 Tirza on 2023 Oct 13 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 114 0 0 .. .. .... .. .. .. .. .. .. .. .. .. -56 8 29 .. .. .. -56 5 44 .... 115 0 0 -56 11 1 18 26 15.2 1 42 -20 -56 50 17 -55 32 47 -56 53 9 -55 30 4 .... 116 0 0 -55 35 0 18 26 15.4 1 41 -20 -56 13 55 -54 57 4 -56 16 46 -54 54 22 0.90 117 0 0 -54 59 0 18 26 16.0 2 40 -20 -55 37 35 -54 21 22 -55 40 24 -54 18 42 1.13 118 0 0 -54 23 2 18 26 16.8 3 40 -20 -55 1 17 -53 45 44 -55 4 5 -53 43 4 1.24 119 0 0 -53 47 9 18 26 17.9 4 39 -20 -54 25 4 -53 10 9 -54 27 50 -53 7 32 1.30 120 0 0 -53 11 23 18 26 19.3 5 38 -20 -53 48 57 -52 34 42 -53 51 42 -52 32 5 1.34 121 0 0 -52 35 44 18 26 21.0 6 37 -20 -53 12 59 -51 59 22 -53 15 42 -51 56 47 1.37 122 0 0 -52 0 16 18 26 22.9 7 36 -20 -52 37 10 -51 24 12 -52 39 51 -51 21 38 1.40 123 0 0 -51 24 58 18 26 25.2 7 36 -20 -52 1 33 -50 49 13 -52 4 13 -50 46 40 1.41 124 0 0 -50 49 54 18 26 27.7 8 35 -20 -51 26 9 -50 14 27 -51 28 47 -50 11 56 1.43 125 0 0 -50 15 4 18 26 30.5 9 34 -20 -50 51 0 -49 39 55 -50 53 37 -49 37 25 1.44 126 0 0 -49 40 30 18 26 33.6 10 33 -20 -50 16 7 -49 5 39 -50 18 42 -49 3 11 1.45 127 0 0 -49 6 14 18 26 37.0 11 32 -20 -49 41 32 -48 31 41 -49 44 6 -48 29 13 1.46 128 0 0 -48 32 17 18 26 40.6 12 32 -20 -49 7 16 -47 58 1 -49 9 49 -47 55 35 1.47 129 0 0 -47 58 40 18 26 44.6 12 31 -19 -48 33 20 -47 24 42 -48 35 52 -47 22 16 1.47 130 0 0 -47 25 25 18 26 48.8 13 30 -19 -47 59 47 -46 51 43 -48 2 18 -46 49 19 1.48 131 0 0 -46 52 33 18 26 53.3 14 29 -19 -47 26 38 -46 19 8 -47 29 7 -46 16 45 1.48 132 0 0 -46 20 6 18 26 58.1 15 28 -19 -46 53 53 -45 46 57 -46 56 20 -45 44 35 1.49 133 0 0 -45 48 4 18 27 3.2 16 27 -18 -46 21 34 -45 15 11 -46 24 0 -45 12 50 1.49 134 0 0 -45 16 28 18 27 8.6 16 27 -18 -45 49 42 -44 43 52 -45 52 7 -44 41 32 1.50 135 0 0 -44 45 21 18 27 14.2 17 26 -18 -45 18 18 -44 13 0 -45 20 42 -44 10 41 1.50 136 0 0 -44 14 43 18 27 20.0 18 25 -17 -44 47 24 -43 42 36 -44 49 46 -43 40 19 1.50 137 0 0 -43 44 34 18 27 26.2 19 24 -17 -44 17 0 -43 12 43 -44 19 21 -43 10 27 1.51 138 0 0 -43 14 57 18 27 32.5 19 23 -17 -43 47 8 -42 43 20 -43 49 28 -42 41 5 1.51 139 0 0 -42 45 52 18 27 39.2 20 22 -16 -43 17 48 -42 14 29 -43 20 7 -42 12 15 1.51 140 0 0 -42 17 20 18 27 46.0 21 21 -16 -42 49 1 -41 46 11 -42 51 19 -41 43 58 1.52 141 0 0 -41 49 22 18 27 53.1 22 20 -15 -42 20 49 -41 18 26 -42 23 6 -41 16 14 1.52 142 0 0 -41 21 59 18 28 0.5 22 19 -15 -41 53 12 -40 51 16 -41 55 28 -40 49 4 1.52 143 0 0 -40 55 11 18 28 8.0 23 19 -14 -41 26 11 -40 24 41 -41 28 26 -40 22 30 1.53 144 0 0 -40 28 59 18 28 15.8 24 18 -14 -40 59 46 -39 58 41 -41 2 0 -39 56 31 1.53 145 0 0 -40 3 24 18 28 23.7 24 17 -13 -40 33 59 -39 33 19 -40 36 12 -39 31 10 1.53 146 0 0 -39 38 28 18 28 31.9 25 16 -13 -40 8 50 -39 8 33 -40 11 2 -39 6 25 1.53 147 0 0 -39 14 9 18 28 40.2 26 15 -12 -39 44 20 -38 44 26 -39 46 31 -38 42 19 1.54 148 0 0 -38 50 30 18 28 48.8 26 14 -11 -39 20 29 -38 20 58 -39 22 40 -38 18 51 1.54 149 0 0 -38 27 30 18 28 57.5 27 13 -11 -38 57 18 -37 58 9 -38 59 28 -37 56 3 1.54 150 0 0 -38 5 11 18 29 6.3 27 12 -10 -38 34 48 -37 36 0 -38 36 57 -37 33 55 1.54 151 0 0 -37 43 32 18 29 15.3 28 11 -9 -38 12 59 -37 14 31 -38 15 8 -37 12 27 1.55 152 0 0 -37 22 35 18 29 24.5 28 10 -9 -37 51 52 -36 53 43 -37 53 59 -36 51 39 1.55 153 0 0 -37 2 19 18 29 33.8 29 9 -8 -37 31 26 -36 33 36 -37 33 33 -36 31 33 1.55 154 0 0 -36 42 45 18 29 43.2 29 8 -7 -37 11 43 -36 14 11 -37 13 50 -36 12 9 1.55 155 0 0 -36 23 54 18 29 52.8 30 7 -7 -36 52 43 -35 55 28 -36 54 49 -35 53 26 1.55 156 0 0 -36 5 45 18 30 2.5 30 5 -6 -36 34 26 -35 37 28 -36 36 31 -35 35 27 1.56 157 0 0 -35 48 20 18 30 12.2 30 4 -5 -36 16 53 -35 20 11 -36 18 57 -35 18 10 1.56 158 0 0 -35 31 39 18 30 22.1 31 3 -4 -36 0 4 -35 3 36 -36 2 7 -35 1 36 1.56 159 0 0 -35 15 41 18 30 32.1 31 2 -3 -35 43 59 -34 47 46 -35 46 2 -34 45 46 1.56 160 0 0 -35 0 27 18 30 42.1 31 1 -3 -35 28 38 -34 32 39 -35 30 41 -34 30 39 1.56 161 0 0 -34 45 58 18 30 52.2 31 360 -2 -35 14 2 -34 18 16 -35 16 4 -34 16 17 1.57 162 0 0 -34 32 13 18 31 2.3 32 359 -1 -35 0 11 -34 4 37 -35 2 13 -34 2 39 1.57 163 0 0 -34 19 13 18 31 12.6 32 358 0 -34 47 5 -33 51 43 -34 49 6 -33 49 45 1.57 164 0 0 -34 6 59 18 31 22.8 32 357 1 -34 34 45 -33 39 34 -34 36 46 -33 37 36 1.57 165 0 0 -33 55 29 18 31 33.1 32 355 1 -34 23 10 -33 28 9 -34 25 10 -33 26 12 1.57 166 0 0 -33 44 45 18 31 43.4 32 354 2 -34 12 21 -33 17 30 -34 14 21 -33 15 33 1.57 167 0 0 -33 34 46 18 31 53.7 32 353 3 -34 2 18 -33 7 35 -34 4 17 -33 5 39 1.57 168 0 0 -33 25 33 18 32 4.1 32 352 4 -33 53 0 -32 58 26 -33 55 0 -32 56 30 1.58 169 0 0 -33 17 6 18 32 14.4 32 351 5 -33 44 29 -32 50 3 -33 46 28 -32 48 7 1.58 170 0 0 -33 9 24 18 32 24.7 32 350 6 -33 36 44 -32 42 25 -33 38 43 -32 40 29 1.58 171 0 0 -33 2 28 18 32 35.0 32 349 6 -33 29 45 -32 35 32 -33 31 44 -32 33 37 1.58 172 0 0 -32 56 19 18 32 45.3 32 348 7 -33 23 32 -32 29 25 -33 25 31 -32 27 30 1.58 173 0 0 -32 50 55 18 32 55.6 32 346 8 -33 18 6 -32 24 4 -33 20 4 -32 22 9 1.58 174 0 0 -32 46 17 18 33 5.8 32 345 9 -33 13 26 -32 19 29 -33 15 24 -32 17 34 1.58 175 0 0 -32 42 26 18 33 16.0 32 344 10 -33 9 33 -32 15 39 -33 11 31 -32 13 44 1.58 176 0 0 -32 39 20 18 33 26.1 32 343 11 -33 6 26 -32 12 35 -33 8 24 -32 10 40 1.58 177 0 0 -32 37 1 18 33 36.1 31 342 12 -33 4 5 -32 10 17 -33 6 3 -32 8 22 1.58 178 0 0 -32 35 28 18 33 46.1 31 341 13 -33 2 31 -32 8 44 -33 4 29 -32 6 50 1.58 179 0 0 -32 34 40 18 33 55.9 31 340 13 -33 1 43 -32 7 58 -33 3 41 -32 6 3 1.58 180 0 0 -32 34 39 18 34 5.7 31 339 14 -33 1 41 -32 7 57 -33 3 39 -32 6 2 1.58 -179 0 0 -32 35 24 18 34 15.4 30 338 15 -33 2 26 -32 8 41 -33 4 24 -32 6 47 1.58 -178 0 0 -32 36 55 18 34 25.0 30 337 16 -33 3 58 -32 10 12 -33 5 56 -32 8 18 1.58 -177 0 0 -32 39 11 18 34 34.5 29 336 17 -33 6 15 -32 12 28 -33 8 12 -32 10 33 1.58 -176 0 0 -32 42 13 18 34 43.9 29 335 18 -33 9 17 -32 15 28 -33 11 15 -32 13 34 1.58 -175 0 0 -32 46 0 18 34 53.1 29 334 19 -33 13 6 -32 19 15 -33 15 4 -32 17 20 1.58 -174 0 0 -32 50 34 18 35 2.2 28 333 20 -33 17 41 -32 23 46 -33 19 39 -32 21 51 1.58 -173 0 0 -32 55 52 18 35 11.2 28 332 20 -33 23 2 -32 29 3 -33 25 0 -32 27 8 1.58 -172 0 0 -33 1 56 18 35 20.0 27 331 21 -33 29 8 -32 35 4 -33 31 6 -32 33 9 1.58 -171 0 0 -33 8 45 18 35 28.7 27 330 22 -33 35 59 -32 41 51 -33 37 58 -32 39 55 1.58 -170 0 0 -33 16 19 18 35 37.2 26 329 23 -33 43 36 -32 49 22 -33 45 35 -32 47 26 1.58 -169 0 0 -33 24 37 18 35 45.5 26 328 24 -33 51 58 -32 57 37 -33 53 57 -32 55 41 1.58 -168 0 0 -33 33 41 18 35 53.7 25 327 25 -34 1 5 -33 6 37 -34 3 4 -33 4 41 1.58 -167 0 0 -33 43 28 18 36 1.6 24 327 25 -34 10 57 -33 16 21 -34 12 56 -33 14 24 1.58 -166 0 0 -33 54 0 18 36 9.4 24 326 26 -34 21 33 -33 26 48 -34 23 33 -33 24 52 1.58 -165 0 0 -34 5 16 18 36 17.0 23 325 27 -34 32 53 -33 38 0 -34 34 54 -33 36 3 1.58 -164 0 0 -34 17 16 18 36 24.4 22 324 28 -34 44 58 -33 49 55 -34 46 59 -33 47 57 1.58 -163 0 0 -34 29 59 18 36 31.6 22 323 29 -34 57 46 -34 2 33 -34 59 47 -34 0 35 1.58 -162 0 0 -34 43 25 18 36 38.6 21 322 30 -35 11 18 -34 15 54 -35 13 20 -34 13 56 1.58 -161 0 0 -34 57 35 18 36 45.4 20 322 30 -35 25 34 -34 29 57 -35 27 36 -34 27 59 1.58 -160 0 0 -35 12 26 18 36 51.9 20 321 31 -35 40 32 -34 44 43 -35 42 34 -34 42 44 1.58 -159 0 0 -35 28 1 18 36 58.2 19 320 32 -35 56 13 -35 0 11 -35 58 16 -34 58 12 1.58 -158 0 0 -35 44 17 18 37 4.3 18 319 33 -36 12 37 -35 16 21 -36 14 40 -35 14 21 1.58 -157 0 0 -36 1 15 18 37 10.1 17 319 33 -36 29 42 -35 33 12 -36 31 46 -35 31 11 1.58 -156 0 0 -36 18 55 18 37 15.7 17 318 34 -36 47 29 -35 50 44 -36 49 33 -35 48 43 1.58 -155 0 0 -36 37 15 18 37 21.1 16 317 35 -37 5 57 -36 8 56 -37 8 2 -36 6 55 1.58 -154 0 0 -36 56 16 18 37 26.2 15 316 35 -37 25 7 -36 27 49 -37 27 12 -36 25 47 1.58 -153 0 0 -37 15 57 18 37 31.0 14 316 36 -37 44 56 -36 47 22 -37 47 3 -36 45 19 1.58 -152 0 0 -37 36 17 18 37 35.6 13 315 37 -38 5 26 -37 7 34 -38 7 33 -37 5 30 1.58 -151 0 0 -37 57 17 18 37 39.9 13 314 37 -38 26 35 -37 28 24 -38 28 43 -37 26 20 1.58 -150 0 0 -38 18 55 18 37 43.9 12 314 38 -38 48 23 -37 49 53 -38 50 32 -37 47 49 1.58 -149 0 0 -38 41 12 18 37 47.7 11 313 38 -39 10 50 -38 12 0 -39 12 59 -38 9 55 1.59 -148 0 0 -39 4 6 18 37 51.2 10 312 39 -39 33 55 -38 34 44 -39 36 5 -38 32 38 1.59 -147 0 0 -39 27 37 18 37 54.4 9 312 40 -39 57 37 -38 58 5 -39 59 48 -38 55 58 1.59 -146 0 0 -39 51 45 18 37 57.3 8 311 40 -40 21 56 -39 22 2 -40 24 8 -39 19 54 1.59 -145 0 0 -40 16 29 18 38 0.0 8 310 41 -40 46 51 -39 46 34 -40 49 4 -39 44 26 1.60 -144 0 0 -40 41 47 18 38 2.3 7 310 41 -41 12 22 -40 11 41 -41 14 35 -40 9 33 1.60 -143 0 0 -41 7 41 18 38 4.4 6 309 41 -41 38 28 -40 37 23 -41 40 42 -40 35 13 1.61 -142 0 0 -41 34 8 18 38 6.2 5 308 42 -42 5 8 -41 3 38 -42 7 23 -41 1 27 1.62 -141 0 0 -42 1 8 18 38 7.6 4 308 42 -42 32 21 -41 30 25 -42 34 37 -41 28 14 1.64 -140 0 0 -42 28 40 18 38 8.8 3 307 43 -43 0 7 -41 57 45 -43 2 24 -41 55 33 1.66 -139 0 0 -42 56 44 18 38 9.7 2 306 43 -43 28 25 -42 25 36 -43 30 43 -42 23 22 1.70 -138 0 0 -43 25 19 18 38 10.4 1 306 43 -43 57 13 -42 53 57 -43 59 33 -42 51 42 1.79 -137 0 0 -43 54 23 18 38 10.7 1 305 43 -44 26 33 -43 22 47 -44 28 53 -43 20 32 2.14 -136 0 0 .. .. .... .. .. .. .. .. .. .. .. .. -43 52 6 .. .. .. -43 49 50 .... Uncertainty in time = +/- 2 secs Prediction of 2023 Aug 27.0 Data for the target star ------------------------ * name: UCAC4 570-032454 * constellation : Gemini * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 06 41 34.7570 DE: +23 56 32.538 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 06 41 34.7571 DE: +23 56 32.538 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.100,0.100) * V mag [mag]: 12.1 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (267) Tirza asteroid class: approx. diameter [km]: 53 approx. diameter ["]: 0.027 distance from Earth [AU]: 2.70930 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#128 date of fit: 2023 Aug 23 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): 0.008", 0.000", 88.194° remarks: * orbital elements for (267)Tirza : Mean anomaly = 168.1823638186 deg Arg. of pericenter = 196.8712794855 deg Long. of node = 73.5858984178 deg Inclination = 6.0094981371 deg Eccentricity = 0.1018713681 Semimajor axis = 2.7731237631 AU Perihelion dist = 2.4906218514 AU Mag: H = 10.29, G = 0.15 Epoch of elements : MJD 60230.77243056 TDT (2023 Oct 13.7724) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#1282023Aug23,5.57,2023,10,13,18.536774,0.118737,-0.834924,5.316364,0.756462,-0.005761,0.000412,0.000000,0.000000 160.6445,23.9205,-101.49,-7.88,False UCAC4 570-032454,6.69298805,23.9423716,0.00,12.09,0.00,0.0,0,,6.71707953,23.9204808,3.78,0.00,0,0,0 267,Tirza,15.84,53.000,2.7093,0,0,1.258,2.45,,2.4,0 0,168.0175,2023,10,13,196.8713,73.5859,6.0095,0.10187,2.77312,2.49062,10.29,5.0,0.15 1.036,0.0083,0.0003,88,0.0083,Known errors,-1.00,0,-1,-1 20231013_032454,60183.00 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2023 Aug 26, 23:58 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org