IOTA/IOTA-ES occultation update for (270) Anahita / 2UCAC 39994976 event on 2008 Oct 16, 18:53 UT Visible from S Australia Summary ------- On 2008 Oct 16 UT, the 51 km diameter asteroid (270) Anahita will occult a 13.4 mag star in the constellation Gemini for observers along a path across S Australia. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.5 mag to 12.8 mag (the magnitude of the asteroid) for at most 6.5 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, TMO astrometry for the asteroid kindly provided by Bill Owen, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 51 * date and approx. time of event: 2008 Oct 16, 18:46 - 2008 Oct 16, 18:56 UT * magnitude of target star: 13.4 * magnitude drop [mag]: 0.5 * estimated maximum duration [s]: 6.5 * Moon: 94 % sunlit, 47° distance * Sun: 106° distance * rough path description: S Australia The occultation path -------------------- * approximate projected width [km]: 93 * 1 sigma uncertainty interval [path widths]: +/- 1.26 * 1 sigma uncertainty interval [seconds]: +/- 8.2 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .057 +/- .053) * 1 sigma uncertainty ellipse (major, minor, PA): ( .057", .053", 90° ) * approx speed of asteroid's shadow [km/s]: 7.8062 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 39994976 by 270 Anahita on 2008 Oct 16 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 ' " Longitude Longitude Longitude Longitude Latitude Latitude Latitude Latitude 155 0 0 -36 41 23 18 56 43 30 353 0 -37 8 52 -36 14 15 -38 19 50 -35 7 22 154 0 0 -36 21 53 18 56 31 30 354 -1 -36 49 14 -35 54 53 -37 59 49 -34 48 19 153 0 0 -36 3 4 18 56 19 31 355 -2 -36 30 17 -35 36 12 -37 40 32 -34 29 56 152 0 0 -35 44 58 18 56 7 31 356 -3 -36 12 4 -35 18 13 -37 21 57 -34 12 15 151 0 0 -35 27 35 18 55 55 31 357 -4 -35 54 33 -35 0 57 -37 4 7 -33 55 15 150 0 0 -35 10 55 18 55 43 32 358 -5 -35 37 46 -34 44 24 -36 47 1 -33 38 58 149 0 0 -34 54 58 18 55 30 32 360 -6 -35 21 43 -34 28 33 -36 30 39 -33 23 23 148 0 0 -34 39 45 18 55 18 32 1 -7 -35 6 23 -34 13 27 -36 15 3 -33 8 30 147 0 0 -34 25 16 18 55 5 32 2 -7 -34 51 48 -33 59 4 -36 0 11 -32 54 21 146 0 0 -34 11 32 18 54 53 32 3 -8 -34 37 58 -33 45 25 -35 46 6 -32 40 55 145 0 0 -33 58 32 18 54 40 33 4 -9 -34 24 52 -33 32 30 -35 32 45 -32 28 13 144 0 0 -33 46 16 18 54 27 33 5 -10 -34 12 32 -33 20 20 -35 20 11 -32 16 15 143 0 0 -33 34 46 18 54 14 33 7 -11 -34 0 57 -33 8 54 -35 8 23 -32 5 0 142 0 0 -33 24 1 18 54 2 33 8 -12 -33 50 7 -32 58 13 -34 57 21 -31 54 30 141 0 0 -33 14 1 18 53 49 33 9 -13 -33 40 3 -32 48 17 -34 47 6 -31 44 44 140 0 0 -33 4 47 18 53 36 33 10 -14 -33 30 45 -32 39 7 -34 37 37 -31 35 42 139 0 0 -32 56 18 18 53 23 33 11 -15 -33 22 12 -32 30 41 -34 28 54 -31 27 25 138 0 0 -32 48 34 18 53 11 33 12 -15 -33 14 26 -32 23 1 -34 20 59 -31 19 52 137 0 0 -32 41 37 18 52 58 33 13 -16 -33 7 25 -32 16 7 -34 13 50 -31 13 5 136 0 0 -32 35 25 18 52 45 33 15 -17 -33 1 10 -32 9 57 -34 7 28 -31 7 2 135 0 0 -32 29 59 18 52 33 33 16 -18 -32 55 42 -32 4 34 -34 1 54 -31 1 44 134 0 0 -32 25 19 18 52 20 32 17 -19 -32 51 0 -31 59 56 -33 57 6 -30 57 11 133 0 0 -32 21 25 18 52 8 32 18 -20 -32 47 4 -31 56 3 -33 53 5 -30 53 23 132 0 0 -32 18 17 18 51 55 32 19 -20 -32 43 54 -31 52 57 -33 49 51 -30 50 19 131 0 0 -32 15 54 18 51 43 32 20 -21 -32 41 30 -31 50 35 -33 47 24 -30 48 1 130 0 0 -32 14 18 18 51 31 31 21 -22 -32 39 53 -31 49 0 -33 45 44 -30 46 28 129 0 0 -32 13 27 18 51 19 31 22 -23 -32 39 2 -31 48 10 -33 44 51 -30 45 39 128 0 0 -32 13 22 18 51 7 31 23 -24 -32 38 56 -31 48 5 -33 44 44 -30 45 35 127 0 0 -32 14 3 18 50 55 30 24 -24 -32 39 37 -31 48 46 -33 45 25 -30 46 16 126 0 0 -32 15 29 18 50 43 30 25 -25 -32 41 3 -31 50 12 -33 46 52 -30 47 42 125 0 0 -32 17 41 18 50 32 30 26 -26 -32 43 16 -31 52 23 -33 49 6 -30 49 52 124 0 0 -32 20 38 18 50 20 29 27 -27 -32 46 14 -31 55 20 -33 52 6 -30 52 46 123 0 0 -32 24 20 18 50 9 29 28 -27 -32 49 57 -31 59 1 -33 55 52 -30 56 25 122 0 0 -32 28 48 18 49 58 28 29 -28 -32 54 26 -32 3 27 -34 0 25 -31 0 48 121 0 0 -32 34 1 18 49 47 28 30 -29 -32 59 41 -32 8 38 -34 5 44 -31 5 55 120 0 0 -32 39 58 18 49 36 27 31 -29 -33 5 40 -32 14 34 -34 11 49 -31 11 46 119 0 0 -32 46 40 18 49 26 27 32 -30 -33 12 24 -32 21 14 -34 18 39 -31 18 21 118 0 0 -32 54 7 18 49 16 26 33 -31 -33 19 53 -32 28 38 -34 26 15 -31 25 39 117 0 0 -33 2 18 18 49 6 25 34 -31 -33 28 7 -32 36 46 -34 34 37 -31 33 41 116 0 0 -33 11 13 18 48 56 25 35 -32 -33 37 5 -32 45 38 -34 43 43 -31 42 26 115 0 0 -33 20 51 18 48 46 24 36 -32 -33 46 47 -32 55 13 -34 53 35 -31 51 53 114 0 0 -33 31 14 18 48 37 24 36 -33 -33 57 14 -33 5 32 -35 4 11 -32 2 4 113 0 0 -33 42 19 18 48 28 23 37 -34 -34 8 23 -33 16 34 -35 15 31 -32 12 56 112 0 0 -33 54 8 18 48 19 22 38 -34 -34 20 16 -33 28 18 -35 27 36 -32 24 31 111 0 0 -34 6 40 18 48 10 21 39 -35 -34 32 52 -33 40 45 -35 40 24 -32 36 47 110 0 0 -34 19 54 18 48 2 21 40 -35 -34 46 11 -33 53 55 -35 53 56 -32 49 45 109 0 0 -34 33 50 18 47 54 20 40 -35 -35 0 13 -34 7 46 -36 8 12 -33 3 25 108 0 0 -34 48 27 18 47 46 19 41 -36 -35 14 56 -34 22 18 -36 23 10 -33 17 45 107 0 0 -35 3 47 18 47 39 19 42 -36 -35 30 21 -34 37 32 -36 38 51 -33 32 45 106 0 0 -35 19 47 18 47 31 18 43 -37 -35 46 27 -34 53 27 -36 55 14 -33 48 26 105 0 0 -35 36 28 18 47 25 17 43 -37 -36 3 15 -35 10 2 -37 12 18 -34 4 46 104 0 0 -35 53 50 18 47 18 16 44 -37 -36 20 43 -35 27 16 -37 30 5 -34 21 46 103 0 0 -36 11 51 18 47 12 15 45 -37 -36 38 51 -35 45 11 -37 48 32 -34 39 25 102 0 0 -36 30 31 18 47 6 15 46 -38 -36 57 39 -36 3 44 -38 7 39 -34 57 42 101 0 0 -36 49 51 18 47 0 14 46 -38 -37 17 6 -36 22 57 -38 27 27 -35 16 37 100 0 0 -37 9 49 18 46 55 13 47 -38 -37 37 12 -36 42 47 -38 47 54 -35 36 9 99 0 0 -37 30 24 18 46 50 12 48 -38 -37 57 56 -37 3 15 -39 9 0 -35 56 18 98 0 0 -37 51 37 18 46 45 11 48 -38 -38 19 17 -37 24 20 -39 30 45 -36 17 4 97 0 0 -38 13 27 18 46 41 10 49 -38 -38 41 16 -37 46 1 -39 53 8 -36 38 26 96 0 0 -38 35 53 18 46 37 10 50 -38 -39 3 51 -38 8 19 -40 16 8 -37 0 23 95 0 0 -38 58 55 18 46 33 9 50 -38 -39 27 2 -38 31 11 -40 39 44 -37 22 54 94 0 0 -39 22 32 18 46 30 8 51 -38 -39 50 49 -38 54 39 -41 3 57 -37 46 0 93 0 0 -39 46 43 18 46 27 7 52 -38 -40 15 10 -39 18 40 -41 28 46 -38 9 39 92 0 0 -40 11 28 18 46 24 6 52 -38 -40 40 5 -39 43 15 -41 54 9 -38 33 51 91 0 0 -40 36 45 18 46 22 5 53 -38 -41 5 33 -40 8 23 -42 20 7 .. .. .. 90 0 0 -41 2 35 18 46 20 4 54 -38 -41 31 34 -40 34 2 -42 46 38 .. .. .. 89 0 0 -41 28 57 18 46 19 4 54 -38 -41 58 7 -41 0 13 -43 13 41 .. .. .. 88 0 0 -41 55 49 18 46 17 3 55 -38 -42 25 10 -41 26 54 -43 41 16 .. .. .. 87 0 0 -42 23 11 18 46 16 2 56 -37 -42 52 44 -41 54 4 -44 9 23 .. .. .. 86 0 0 -42 51 2 18 46 16 1 56 -37 -43 20 47 -42 21 44 -44 37 59 .. .. .. 85 0 0 -43 19 21 18 46 16 0 57 -37 .. .. .. -42 49 51 .. .. .. .. .. .. Uncertainty in time = +/- 9 secs [Prediction of 2008 Oct 1.0] Data for the target star ------------------------ * name: 2UCAC 39994976 * constellation : Gemini * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 06 32 06.4113 DE: +23 24 14.052 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .056, .053 ) * V mag [mag]: 13.4 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (270) Anahita approx. diameter [km]: 51 approx. diameter ["]: .042 distance from Earth [AU]: 1.68700 * orbital information: orbit source: Preston date of fit: 2008 Sep 30 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 944 number of rejected observations: 127 time covered by the observations: 1900 Sep 20 - 2008 Sep 25 1 sigma uncertainty ellipse (major, minor, PA): 0.012, 0.007, 96° remarks: * orbital elements for (270) Anahita : Mean anomaly = 79.32472760 deg Arg. of pericenter = 80.27783304 deg Long. of node = 254.55433963 deg Inclination = 2.36576859 deg Eccentricity = 0.15023939 Semimajor axis = 2.19842646 AU Perihelion dist = 1.86813621 AU Mag: H = 8.71, G = 0.15 Epoch of elements : MJD 54755.78700000 TDT (2008 Oct 16.787) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Oct 16 270 Anahita 18h 53.7m UT 13.4 6 32 6.411 23 24 14.052UCAC 39994976 0.0 12.8 51 6.5 1.687 1.648 -3.52 148.9491 23.404 -107.06 -9.23 18.8945 -0.12779 -0.82772 4.35404 -0.67486 -0.00524 0.00028 2000 77.57492320081011.00000 80.277833254.554340 2.3657690.15023939 2.1984265 1.8681362 8.8 5.00.15 RATE 3.0236820 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.057 0.053 90 2.26 0.053 0 54740.5020081016_994976 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Oct 01, 05:02 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org