IOTA/IOTA-ES occultation update for (36) Atalante / UCAC2 14889639 event on 2009 Oct 11, 10:30 UT Visible from Summary ------- On 2009 Oct 11 UT, the 106 km diameter asteroid (36) Atalante will occult a 11.8 mag star in the constellation Scorpius for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 2.7 mag to 14.4 mag (the magnitude of the asteroid) for at most 3.8 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: 76 * date and approx. time of event: 2009 Oct 11, 10:31 - 2009 Oct 11, 10:33 UT * magnitude of target star: 11.8 * magnitude drop [mag]: 2.7 * estimated maximum duration [s]: 3.8 * Moon: 50 % sunlit, 151° distance * Sun: 66° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 113 * 1 sigma uncertainty interval [path widths]: +/- 0.73 * 1 sigma uncertainty interval [seconds]: +/- 2.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .036 +/- .032) * 1 sigma uncertainty ellipse (major, minor, PA): ( .036", .032", 92° ) * approx speed of asteroid's shadow [km/s]: 27.7400 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC2 14889639 by 36 Atalante on 2009 Oct 11 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 119 0 0 -51 23 28 10 31 19 62 281 -1 -52 0 47 -50 46 20 -52 55 34 -49 52 26 120 0 0 -50 56 51 10 31 22 62 279 -1 -51 34 24 -50 19 29 -52 29 33 -49 25 14 121 0 0 -50 29 28 10 31 25 61 277 -2 -51 7 15 -49 51 52 -52 2 46 -48 57 16 122 0 0 -50 1 19 10 31 28 61 275 -3 -50 39 21 -49 23 28 -51 35 13 -48 28 32 123 0 0 -49 32 22 10 31 31 60 274 -4 -50 10 38 -48 54 17 -51 6 52 -47 59 1 124 0 0 -49 2 38 10 31 34 59 272 -4 -49 41 9 -48 24 18 -50 37 44 -47 28 41 125 0 0 -48 32 5 10 31 37 59 270 -5 -49 10 50 -47 53 31 -50 7 47 -46 57 33 126 0 0 -48 0 42 10 31 40 58 269 -6 -48 39 42 -47 21 54 -49 37 1 -46 25 36 127 0 0 -47 28 30 10 31 43 57 267 -7 -48 7 45 -46 49 28 -49 5 25 -45 52 49 128 0 0 -46 55 28 10 31 47 57 266 -8 -47 34 57 -46 16 11 -48 32 59 -45 19 12 129 0 0 -46 21 35 10 31 50 56 264 -9 -47 1 18 -45 42 4 -47 59 42 -44 44 45 130 0 0 -45 46 51 10 31 53 55 263 -9 -46 26 48 -45 7 6 -47 25 33 -44 9 26 131 0 0 -45 11 15 10 31 56 54 261 -10 -45 51 27 -44 31 17 -46 50 32 -43 33 17 132 0 0 -44 34 48 10 32 0 54 260 -11 -45 15 13 -43 54 36 -46 14 39 -42 56 17 133 0 0 -43 57 28 10 32 3 53 258 -12 -44 38 7 -43 17 3 -45 37 54 -42 18 25 134 0 0 -43 19 17 10 32 6 52 257 -13 -44 0 9 -42 38 39 -45 0 15 -41 39 42 135 0 0 -42 40 14 10 32 9 51 256 -14 -43 21 19 -41 59 22 -44 21 44 -41 0 8 136 0 0 -42 0 18 10 32 13 50 255 -15 -42 41 36 -41 19 15 -43 42 21 -40 19 42 137 0 0 -41 19 31 10 32 16 49 253 -16 -42 1 1 -40 38 15 -43 2 4 -39 38 26 138 0 0 -40 37 53 10 32 19 48 252 -17 -41 19 34 -39 56 25 -42 20 55 -38 56 19 139 0 0 -39 55 23 10 32 23 47 251 -18 -40 37 16 -39 13 45 -41 38 54 -38 13 22 140 0 0 -39 12 3 10 32 26 46 250 -19 -39 54 7 -38 30 14 -40 56 1 -37 29 36 141 0 0 -38 27 53 10 32 29 45 249 -20 -39 10 7 -37 45 54 -40 12 17 -36 45 2 142 0 0 -37 42 54 10 32 33 44 248 -21 -38 25 18 -37 0 45 -39 27 42 -35 59 40 143 0 0 -36 57 7 10 32 36 43 247 -22 -37 39 40 -36 14 49 -38 42 18 -35 13 31 144 0 0 -36 10 33 10 32 39 42 246 -23 -36 53 15 -35 28 7 -37 56 5 -34 26 36 145 0 0 -35 23 13 10 32 43 41 245 -24 -36 6 3 -34 40 39 -37 9 5 -33 38 58 146 0 0 -34 35 9 10 32 46 40 244 -25 -35 18 6 -33 52 28 -36 21 18 -32 50 37 147 0 0 -33 46 22 10 32 49 39 243 -26 -34 29 25 -33 3 35 -35 32 47 -32 1 35 148 0 0 -32 56 53 10 32 52 38 243 -28 -33 40 2 -32 14 1 -34 43 33 -31 11 53 149 0 0 -32 6 46 10 32 55 37 242 -29 -32 50 0 -31 23 48 -33 53 38 -30 21 34 150 0 0 -31 16 0 10 32 58 36 241 -30 -31 59 18 -30 32 59 -33 3 3 -29 30 39 151 0 0 -30 24 40 10 33 1 34 240 -31 -31 8 1 -29 41 35 -32 11 51 -28 39 10 152 0 0 -29 32 46 10 33 4 33 240 -32 -30 16 10 -28 49 39 -31 20 3 -27 47 11 153 0 0 -28 40 21 10 33 7 32 239 -34 -29 23 47 -27 57 13 -30 27 42 -26 54 42 154 0 0 -27 47 28 10 33 10 31 238 -35 -28 30 54 -27 4 18 -29 34 51 -26 1 47 155 0 0 -26 54 9 10 33 13 30 238 -36 -27 37 35 -26 10 59 -28 41 32 -25 8 28 156 0 0 -26 0 26 10 33 15 28 237 -37 -26 43 51 -25 17 18 -27 47 47 -24 14 48 157 0 0 -25 6 23 10 33 18 27 236 -38 -25 49 46 -24 23 16 -26 53 40 -23 20 49 158 0 0 -24 12 2 10 33 20 26 236 -40 -24 55 23 -23 28 58 -25 59 12 -22 26 34 159 0 0 -23 17 26 10 33 23 25 235 -41 -24 0 43 -22 34 25 -25 4 28 -21 32 6 160 0 0 -22 22 38 10 33 25 23 235 -42 -23 5 51 -21 39 41 -24 9 29 -20 37 28 161 0 0 -21 27 40 10 33 27 22 234 -44 -22 10 49 -20 44 48 -23 14 20 -19 42 42 162 0 0 -20 32 37 10 33 29 21 234 -45 -21 15 39 -19 49 50 -22 19 2 -18 47 52 163 0 0 -19 37 30 10 33 31 19 234 -46 -20 20 26 -18 54 50 -21 23 39 -17 53 1 164 0 0 -18 42 22 10 33 33 18 233 -47 -19 25 12 -17 59 49 -20 28 14 -16 58 10 165 0 0 -17 47 17 10 33 35 17 233 -49 -18 29 59 -17 4 52 -19 32 49 -16 3 24 166 0 0 -16 52 18 10 33 36 15 232 -50 -17 34 51 -16 10 1 -18 37 29 -15 8 45 167 0 0 -15 57 27 10 33 38 14 232 -51 -16 39 51 -15 15 19 -17 42 15 -14 14 16 168 0 0 -15 2 47 10 33 39 13 232 -53 -15 45 1 -14 20 49 -16 47 11 -13 19 59 169 0 0 -14 8 21 10 33 40 12 232 -54 -14 50 25 -13 26 32 -15 52 19 -12 25 57 170 0 0 -13 14 11 10 33 41 10 231 -55 -13 56 4 -12 32 33 -14 57 42 -11 32 13 171 0 0 -12 20 20 10 33 42 9 231 -57 -13 2 2 -11 38 54 -14 3 24 -10 38 49 172 0 0 -11 26 51 10 33 43 8 231 -58 -12 8 21 -10 45 36 -13 9 26 - 9 45 48 173 0 0 -10 33 46 10 33 44 6 231 -59 -11 15 4 - 9 52 43 -12 15 50 - 8 53 12 174 0 0 - 9 41 7 10 33 44 5 231 -61 -10 22 13 - 9 0 16 -11 22 40 - 8 1 2 175 0 0 - 8 48 56 10 33 45 4 230 -62 - 9 29 49 - 8 8 18 -10 29 58 - 7 9 22 176 0 0 - 7 57 16 10 33 45 2 230 -63 - 8 37 56 - 7 16 51 - 9 37 45 - 6 18 14 177 0 0 - 7 6 9 10 33 45 1 230 -64 - 7 46 35 - 6 25 56 - 8 46 5 .. .. .. Uncertainty in time = +/- 3 secs [Prediction of 2008 Mar 20.0] Data for the target star ------------------------ * name: UCAC2 14889639 * constellation : Scorpius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 17 23 14.8618 DE: -39 42 06.449 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .030, .030 ) * V mag [mag]: 11.8 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (36) Atalante approx. diameter [km]: 106 approx. diameter ["]: .044 distance from Earth [AU]: 3.29300 * orbital information: orbit source: Preston date of fit: 2008 Mar 20 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 615 number of rejected observations: 50 time covered by the observations: 1901 Sep 22 - 2008 Feb 16 1 sigma uncertainty ellipse (major, minor, PA): 0.020, 0.011, 98° remarks: * orbital elements for (36) Atalante : Mean anomaly = 267.17362461 deg Arg. of pericenter = 46.96655353 deg Long. of node = 358.46116462 deg Inclination = 18.43424022 deg Eccentricity = 0.30339063 Semimajor axis = 2.74680082 AU Perihelion dist = 1.91344719 AU Mag: H = 8.58, G = 0.15 Epoch of elements : MJD 55115.43800000 TDT (2009 Oct 11.438) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Oct 11 36 Atalante 10h 30.1m UT 11.8 17 23 14.862-39 42 6.45UCAC2 14889639 0.0 14.4 106 3.8 3.293 3.547 8.54 83.1256 -39.704 19.15 -7.16 10.5025 0.06912 -0.33732 15.32727 3.19737 0.00522 -0.00105 2000 265.996283200910 6.00000 46.966554358.461165 18.4342400.30339063 2.7468008 1.9134472 8.5 5.00.15 RATE 2.1650270 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.036 0.032 92 1.73 0.032 0 54545.5020091011_889639 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 20, 14:34 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org