IOTA/IOTA-ES occultation update for (2685) Masursky / TYC 0730-02388-1 event on 2012 Dec 07, 15:27 UT Visible from Tasmania Summary ------- On 2012 Dec 07 UT, the 13 km diameter asteroid (2685) Masursky will occult a 9.4 mag star in the constellation Orion for observers along a path across Tasmania. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.0 mag to 15.4 mag (the magnitude of the asteroid) for at most 1.2 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 13 * date and approx. time of event: 2012 Dec 07, 15:21 - 2012 Dec 07, 15:34 UT * geocentric midpoint of event [JD]: 2456269.14406667 * magnitude of target star: 9.4 * magnitude drop [mag]: 6.0 * estimated maximum duration [s]: 1.2 * Moon: 40 % sunlit, 84° distance * Sun: 157° distance * rough path description: Tasmania The occultation path -------------------- * approximate projected width [km]: 19 * 1 sigma uncertainty interval [path widths]: +/- 5.23 * 1 sigma uncertainty interval [seconds]: +/- 7.8 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .083 +/- .054) * 1 sigma uncertainty ellipse (major, minor, PA): ( .084", .053", 96° ) * approx speed of asteroid's shadow [km/s]: 10.2417 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 0730-02388-1 by 2685 Masursky on 2012 Dec 7 Centre Star Star Sun Path Limits Error Limits E. Longitude Latitude U.T. Alt Az Alt Limit 1 Limit 2 Limit 3 Limit 4 o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " Latitude Latitude Latitude Latitude 97 0 0 -64 43 2 15 34 25 10 46 0 -64 36 57 -64 49 8 -63 34 8 -65 53 41 98 0 0 -64 25 55 15 34 24 11 45 -1 -64 19 49 -64 32 2 -63 16 44 -65 36 52 99 0 0 -64 8 24 15 34 22 11 44 -1 -64 2 16 -64 14 32 -62 58 55 -65 19 39 100 0 0 -63 50 27 15 34 21 12 43 -2 -63 44 18 -63 56 37 -62 40 42 -65 2 1 101 0 0 -63 32 6 15 34 19 12 42 -2 -63 25 55 -63 38 18 -62 22 5 -64 43 57 102 0 0 -63 13 19 15 34 17 13 41 -2 -63 7 7 -63 19 32 -62 3 2 -64 25 28 103 0 0 -62 54 7 15 34 15 13 41 -3 -62 47 54 -63 0 22 -61 43 34 -64 6 33 104 0 0 -62 34 30 15 34 13 14 40 -3 -62 28 15 -62 40 46 -61 23 41 -63 47 12 105 0 0 -62 14 27 15 34 11 14 39 -4 -62 8 10 -62 20 44 -61 3 23 -63 27 26 106 0 0 -61 53 58 15 34 9 15 38 -4 -61 47 40 -62 0 17 -60 42 40 -63 7 13 107 0 0 -61 33 4 15 34 6 15 37 -5 -61 26 44 -61 39 23 -60 21 32 -62 46 33 108 0 0 -61 11 43 15 34 4 16 36 -5 -61 5 23 -61 18 4 -59 59 58 -62 25 28 109 0 0 -60 49 57 15 34 1 17 35 -6 -60 43 36 -60 56 20 -59 37 59 -62 3 56 110 0 0 -60 27 46 15 33 59 17 34 -6 -60 21 23 -60 34 9 -59 15 36 -61 41 58 111 0 0 -60 5 9 15 33 56 18 33 -7 -59 58 45 -60 11 33 -58 52 47 -61 19 33 112 0 0 -59 42 6 15 33 53 18 32 -7 -59 35 42 -59 48 32 -58 29 33 -60 56 43 113 0 0 -59 18 39 15 33 49 19 31 -8 -59 12 13 -59 25 5 -58 5 55 -60 33 27 114 0 0 -58 54 46 15 33 46 19 30 -8 -58 48 19 -59 1 13 -57 41 53 -60 9 44 115 0 0 -58 30 28 15 33 43 20 30 -9 -58 24 1 -58 36 56 -57 17 26 -59 45 36 116 0 0 -58 5 46 15 33 39 21 29 -9 -57 59 18 -58 12 15 -56 52 36 -59 21 3 117 0 0 -57 40 39 15 33 35 21 28 -10 -57 34 11 -57 47 9 -56 27 22 -58 56 5 118 0 0 -57 15 9 15 33 31 22 27 -10 -57 8 40 -57 21 39 -56 1 45 -58 30 41 119 0 0 -56 49 15 15 33 27 23 26 -11 -56 42 45 -56 55 46 -55 35 46 -58 4 54 120 0 0 -56 22 58 15 33 23 23 25 -11 -56 16 28 -56 29 29 -55 9 24 -57 38 43 121 0 0 -55 56 19 15 33 19 24 24 -11 -55 49 48 -56 2 50 -54 42 40 -57 12 8 122 0 0 -55 29 18 15 33 14 24 23 -12 -55 22 47 -55 35 49 -54 15 36 -56 45 10 123 0 0 -55 1 55 15 33 10 25 22 -12 -54 55 24 -55 8 27 -53 48 11 -56 17 50 124 0 0 -54 34 11 15 33 5 26 21 -13 -54 27 40 -54 40 44 -53 20 26 -55 50 8 125 0 0 -54 6 8 15 33 0 26 20 -13 -53 59 37 -54 12 40 -52 52 22 -55 22 5 126 0 0 -53 37 45 15 32 54 27 19 -14 -53 31 14 -53 44 17 -52 23 59 -54 53 42 127 0 0 -53 9 3 15 32 49 28 18 -14 -53 2 32 -53 15 35 -51 55 19 -54 24 59 128 0 0 -52 40 4 15 32 43 28 17 -15 -52 33 33 -52 46 36 -51 26 21 -53 55 58 129 0 0 -52 10 47 15 32 38 29 16 -15 -52 4 17 -52 17 19 -50 57 7 -53 26 38 130 0 0 -51 41 15 15 32 32 30 15 -16 -51 34 44 -51 47 46 -50 27 38 -52 57 1 131 0 0 -51 11 26 15 32 26 30 14 -16 -51 4 56 -51 17 57 -49 57 55 -52 27 8 132 0 0 -50 41 24 15 32 19 31 13 -17 -50 34 54 -50 47 54 -49 27 58 -51 57 0 133 0 0 -50 11 8 15 32 13 31 12 -17 -50 4 39 -50 17 38 -48 57 48 -51 26 38 134 0 0 -49 40 40 15 32 6 32 11 -17 -49 34 11 -49 47 9 -48 27 26 -50 56 2 135 0 0 -49 10 0 15 31 59 33 10 -18 -49 3 32 -49 16 28 -47 56 54 -50 25 14 136 0 0 -48 39 9 15 31 52 33 9 -18 -48 32 42 -48 45 37 -47 26 12 -49 54 14 137 0 0 -48 8 10 15 31 45 34 8 -19 -48 1 43 -48 14 36 -46 55 21 -49 23 4 138 0 0 -47 37 1 15 31 38 34 6 -19 -47 30 36 -47 43 27 -46 24 23 -48 51 45 139 0 0 -47 5 46 15 31 30 35 5 -19 -46 59 22 -47 12 11 -45 53 18 -48 20 19 140 0 0 -46 34 24 15 31 23 36 4 -20 -46 28 1 -46 40 48 -45 22 7 -47 48 45 141 0 0 -46 2 57 15 31 15 36 3 -20 -45 56 35 -46 9 20 -44 50 52 -47 17 5 142 0 0 -45 31 26 15 31 7 37 2 -20 -45 25 5 -45 37 48 -44 19 33 -46 45 21 143 0 0 -44 59 52 15 30 59 37 1 -21 -44 53 32 -45 6 13 -43 48 12 -46 13 33 144 0 0 -44 28 17 15 30 51 38 359 -21 -44 21 58 -44 34 36 -43 16 50 -45 41 43 145 0 0 -43 56 40 15 30 42 38 358 -21 -43 50 23 -44 2 59 -42 45 27 -45 9 52 146 0 0 -43 25 4 15 30 34 39 357 -21 -43 18 48 -43 31 21 -42 14 5 -44 38 0 147 0 0 -42 53 29 15 30 25 39 356 -22 -42 47 15 -42 59 45 -41 42 45 -44 6 10 148 0 0 -42 21 57 15 30 16 40 354 -22 -42 15 44 -42 28 12 -41 11 28 -43 34 22 149 0 0 -41 50 29 15 30 8 40 353 -22 -41 44 17 -41 56 42 -40 40 15 -43 2 37 150 0 0 -41 19 5 15 29 59 41 352 -22 -41 12 54 -41 25 17 -40 9 6 -42 30 56 151 0 0 -40 47 47 15 29 49 41 350 -22 -40 41 38 -40 53 57 -39 38 4 -41 59 21 152 0 0 -40 16 36 15 29 40 41 349 -23 -40 10 28 -40 22 44 -39 7 9 -41 27 52 153 0 0 -39 45 32 15 29 31 42 348 -23 -39 39 26 -39 51 39 -38 36 22 -40 56 31 154 0 0 -39 14 38 15 29 21 42 346 -23 -39 8 33 -39 20 43 -38 5 44 -40 25 18 155 0 0 -38 43 53 15 29 12 42 345 -23 -38 37 50 -38 49 57 -37 35 16 -39 54 16 156 0 0 -38 13 19 15 29 2 43 344 -23 -38 7 17 -38 19 22 -37 4 59 -39 23 23 157 0 0 -37 42 57 15 28 53 43 342 -23 -37 36 56 -37 48 58 -36 34 53 -38 52 43 158 0 0 -37 12 47 15 28 43 43 341 -23 -37 6 48 -37 18 47 -36 5 1 -38 22 15 159 0 0 -36 42 51 15 28 33 43 339 -23 -36 36 54 -36 48 49 -35 35 22 -37 52 1 160 0 0 -36 13 10 15 28 23 44 338 -23 -36 7 14 -36 19 6 -35 5 57 -37 22 1 161 0 0 -35 43 44 15 28 13 44 337 -23 -35 37 50 -35 49 39 -34 36 48 -36 52 17 162 0 0 -35 14 34 15 28 3 44 335 -23 -35 8 41 -35 20 27 -34 7 56 -36 22 49 163 0 0 -34 45 41 15 27 53 44 334 -23 -34 39 50 -34 51 33 -33 39 20 -35 53 38 164 0 0 -34 17 6 15 27 43 44 332 -23 -34 11 17 -34 22 57 -33 11 2 -35 24 45 165 0 0 -33 48 50 15 27 33 44 331 -23 -33 43 2 -33 54 39 -32 43 2 -34 56 10 166 0 0 -33 20 53 15 27 23 44 329 -22 -33 15 7 -33 26 40 -32 15 22 -34 27 55 167 0 0 -32 53 16 15 27 13 44 328 -22 -32 47 31 -32 59 2 -31 48 2 -34 0 1 168 0 0 -32 26 0 15 27 3 44 327 -22 -32 20 17 -32 31 45 -31 21 2 -33 32 27 169 0 0 -31 59 6 15 26 53 44 325 -22 -31 53 24 -32 4 49 -30 54 24 -33 5 15 170 0 0 -31 32 33 15 26 43 44 324 -22 -31 26 53 -31 38 15 -30 28 8 -32 38 26 171 0 0 -31 6 24 15 26 33 44 322 -21 -31 0 45 -31 12 4 -30 2 14 -32 11 59 172 0 0 -30 40 38 15 26 23 43 321 -21 -30 35 0 -30 46 16 -29 36 43 -31 45 56 173 0 0 -30 15 16 15 26 13 43 320 -21 -30 9 39 -30 20 53 -29 11 37 -31 20 17 174 0 0 -29 50 18 15 26 3 43 318 -20 -29 44 43 -29 55 54 -28 46 55 -30 55 3 175 0 0 -29 25 46 15 25 53 43 317 -20 -29 20 12 -29 31 20 -28 22 37 -30 30 15 176 0 0 -29 1 39 15 25 44 43 316 -20 -28 56 6 -29 7 12 -27 58 45 -30 5 52 177 0 0 -28 37 58 15 25 34 42 315 -19 -28 32 27 -28 43 30 -27 35 19 -29 41 56 178 0 0 -28 14 44 15 25 24 42 313 -19 -28 9 15 -28 20 15 -27 12 19 -29 18 27 179 0 0 -27 51 58 15 25 14 41 312 -19 -27 46 29 -27 57 27 -26 49 47 -28 55 25 180 0 0 -27 29 38 15 25 5 41 311 -18 -27 24 11 -27 35 6 -26 27 41 -28 32 52 -179 0 0 -27 7 47 15 24 55 41 310 -18 -27 2 21 -27 13 14 -26 6 3 -28 10 46 -178 0 0 -26 46 24 15 24 46 40 309 -17 -26 40 59 -26 51 50 -25 44 54 -27 49 9 -177 0 0 -26 25 30 15 24 37 40 308 -17 -26 20 7 -26 30 55 -25 24 13 -27 28 2 -176 0 0 -26 5 6 15 24 27 39 306 -16 -25 59 43 -26 10 29 -25 4 0 -27 7 24 -175 0 0 -25 45 11 15 24 18 39 305 -16 -25 39 49 -25 50 33 -24 44 18 -26 47 16 -174 0 0 -25 25 46 15 24 9 38 304 -15 -25 20 25 -25 31 7 -24 25 4 -26 27 38 -173 0 0 -25 6 51 15 24 0 38 303 -15 -25 1 31 -25 12 11 -24 6 21 -26 8 31 -172 0 0 -24 48 26 15 23 52 37 302 -14 -24 43 8 -24 53 45 -23 48 8 -25 49 55 -171 0 0 -24 30 33 15 23 43 37 301 -14 -24 25 16 -24 35 51 -23 30 25 -25 31 50 -170 0 0 -24 13 11 15 23 34 36 301 -13 -24 7 54 -24 18 28 -23 13 14 -25 14 17 -169 0 0 -23 56 20 15 23 26 35 300 -12 -23 51 5 -24 1 37 -22 56 34 -24 57 15 -168 0 0 -23 40 2 15 23 18 35 299 -12 -23 34 47 -23 45 17 -22 40 25 -24 40 46 -167 0 0 -23 24 15 15 23 10 34 298 -11 -23 19 1 -23 29 29 -22 24 47 -24 24 49 -166 0 0 -23 9 1 15 23 2 33 297 -11 -23 3 47 -23 14 14 -22 9 42 -24 9 25 -165 0 0 -22 54 19 15 22 54 33 296 -10 -22 49 6 -22 59 31 -21 55 9 -23 54 34 -164 0 0 -22 40 10 15 22 46 32 296 -9 -22 34 58 -22 45 22 -21 41 8 -23 40 16 -163 0 0 -22 26 33 15 22 38 31 295 -9 -22 21 23 -22 31 45 -21 27 40 -23 26 32 -162 0 0 -22 13 31 15 22 31 31 294 -8 -22 8 20 -22 18 41 -21 14 45 -23 13 21 -161 0 0 -22 1 1 15 22 24 30 294 -7 -21 55 52 -22 6 11 -21 2 23 -23 0 44 -160 0 0 -21 49 5 15 22 17 29 293 -7 -21 43 56 -21 54 15 -20 50 34 -22 48 40 -159 0 0 -21 37 43 15 22 10 28 292 -6 -21 32 35 -21 42 52 -20 39 18 -22 37 12 -158 0 0 -21 26 55 15 22 3 28 292 -5 -21 21 48 -21 32 4 -20 28 37 -22 26 17 -157 0 0 -21 16 42 15 21 56 27 291 -4 -21 11 34 -21 21 49 -20 18 29 -22 15 57 -156 0 0 -21 7 2 15 21 50 26 290 -4 -21 1 55 -21 12 9 -20 8 55 -22 6 12 -155 0 0 -20 57 57 15 21 44 25 290 -3 -20 52 51 -21 3 4 -19 59 55 -21 57 2 -154 0 0 -20 49 27 15 21 38 24 289 -2 -20 44 21 -20 54 34 -19 51 29 -21 48 27 -153 0 0 -20 41 32 15 21 32 24 289 -1 -20 36 26 -20 46 38 -19 43 38 -21 40 27 -152 0 0 -20 34 12 15 21 26 23 288 -1 -20 29 6 -20 39 17 -19 36 22 -21 33 3 Uncertainty in time = +/- 9 secs Prediction of 2012 Dec 3.0 Data for the target star ------------------------ * name: TYC 0730-02388-1 * constellation : Orion * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 06 11 18.0283 DE: +07 49 22.756 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .024, .025 ) * V mag [mag]: 9.4 * B mag [mag]: 9.7 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (2685) Masursky approx. diameter [km]: 13 approx. diameter ["]: .012 distance from Earth [AU]: 1.45600 * orbital information: orbit source: Preston date of fit: 2012 Jul 10 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 819 number of rejected observations: 16 time covered by the observations: 1973 Aug 28 - 2011 Dec 25 1 sigma uncertainty ellipse (major, minor, PA): 0.080, 0.047, 97° remarks: * orbital elements for (2685) Masursky : Mean anomaly = 313.38511922 deg Arg. of pericenter = 287.76530031 deg Long. of node = 215.39886878 deg Inclination = 12.12892074 deg Eccentricity = 0.11011938 Semimajor axis = 2.56992302 AU Perihelion dist = 2.28692468 AU Mag: H = 12.03, G = 0.15 Epoch of elements : MJD 56268.64400000 TDT (2012 Dec 07.644) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Dec 7 2685 Masursky 15h 27.5m UT 9.4 6 11 18.028 7 49 22.76TYC 0730-02388-1 9.7 15.4 13 1.2 1.456 -2.131 -14.72 144.1574 7.826 -53.93 -22.69 15.4576 0.30252 -0.64997 -5.24129 -2.43836 -0.00171 0.00152 2000 311.31717620121129.00000287.765300215.398869 12.1289210.11011938 2.5699230 2.286924712.1 5.00.15 RATE 2.3923450 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.084 0.053 96 6.23 0.064 0 0 3-4 056264.0020121207_2388-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Jul 10, 04:43 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org