IOTA/IOTA-ES occultation update for (212) Medea / 2UCAC 21615068 event on 2008 Nov 06, 11:01 UT Visible from Australia Summary ------- On 2008 Nov 06 UT, the 136 km diameter asteroid (212) Medea will occult a 12.5 mag star in the constellation Sagittarius 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 2.2 mag to 14.6 mag (the magnitude of the asteroid) for at most 3.9 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: 59 * date and approx. time of event: 2008 Nov 06, 11:02 - 2008 Nov 06, 11:03 UT * midpoint of event [JD]: 2454776.9589 * magnitude of target star: 12.5 * magnitude drop [mag]: 2.2 * estimated maximum duration [s]: 3.9 * Moon: 53 % sunlit, 45° distance * Sun: 49° distance * rough path description: Australia The occultation path -------------------- * approximate projected width [km]: 145 * 1 sigma uncertainty interval [path widths]: +/- 1.05 * 1 sigma uncertainty interval [seconds]: +/- 3.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .052 +/- .051) * 1 sigma uncertainty ellipse (major, minor, PA): ( .052", .051", 90° ) * approx speed of asteroid's shadow [km/s]: 35.1227 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 21615068 by 212 Medea on 2008 Nov 6 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 113 0 0 -35 50 18 11 2 39 45 269 -1 -36 33 27 -35 7 21 -38 4 52 -33 37 51 114 0 0 -35 28 40 11 2 41 44 268 -1 -36 11 55 -34 45 38 -37 43 30 -33 15 57 115 0 0 -35 6 41 11 2 43 44 267 -2 -35 50 1 -34 23 34 -37 21 47 -32 53 43 116 0 0 -34 44 21 11 2 45 43 266 -3 -35 27 46 -34 1 10 -36 59 43 -32 31 9 117 0 0 -34 21 42 11 2 47 42 266 -4 -35 5 12 -33 38 25 -36 37 19 -32 8 14 118 0 0 -33 58 42 11 2 49 41 265 -5 -34 42 17 -33 15 21 -36 14 34 -31 45 1 119 0 0 -33 35 22 11 2 52 40 264 -6 -34 19 2 -32 51 57 -35 51 30 -31 21 27 120 0 0 -33 11 44 11 2 54 39 263 -7 -33 55 27 -32 28 14 -35 28 5 -30 57 35 121 0 0 -32 47 46 11 2 56 38 262 -8 -33 31 34 -32 4 12 -35 4 21 -30 33 24 122 0 0 -32 23 29 11 2 58 38 262 -9 -33 7 22 -31 39 51 -34 40 18 -30 8 55 123 0 0 -31 58 54 11 2 59 37 261 -10 -32 42 51 -31 15 12 -34 15 56 -29 44 8 124 0 0 -31 34 2 11 3 1 36 260 -11 -32 18 2 -30 50 15 -33 51 15 -29 19 3 125 0 0 -31 8 52 11 3 3 35 259 -12 -31 52 56 -30 25 2 -33 26 17 -28 53 42 126 0 0 -30 43 24 11 3 5 34 259 -13 -31 27 32 -29 59 31 -33 1 2 -28 28 4 127 0 0 -30 17 41 11 3 7 33 258 -14 -31 1 52 -29 33 44 -32 35 29 -28 2 10 128 0 0 -29 51 41 11 3 9 32 257 -15 -30 35 56 -29 7 41 -32 9 39 -27 36 1 129 0 0 -29 25 26 11 3 10 31 257 -16 -30 9 44 -28 41 23 -31 43 34 -27 9 36 130 0 0 -28 58 56 11 3 12 30 256 -17 -29 43 16 -28 14 50 -31 17 13 -26 42 58 131 0 0 -28 32 12 11 3 14 29 256 -18 -29 16 35 -27 48 3 -30 50 37 -26 16 6 132 0 0 -28 5 14 11 3 15 28 255 -19 -28 49 39 -27 21 3 -30 23 47 -25 49 0 133 0 0 -27 38 2 11 3 17 27 254 -20 -28 22 30 -26 53 49 -29 56 42 -25 21 42 134 0 0 -27 10 39 11 3 18 26 254 -21 -27 55 8 -26 26 24 -29 29 25 -24 54 12 135 0 0 -26 43 3 11 3 20 25 253 -22 -27 27 34 -25 58 46 -29 1 55 -24 26 31 136 0 0 -26 15 16 11 3 21 24 253 -23 -26 59 49 -25 30 58 -28 34 13 -23 58 40 137 0 0 -25 47 19 11 3 23 23 252 -24 -26 31 53 -25 2 59 -28 6 20 -23 30 38 138 0 0 -25 19 11 11 3 24 22 252 -25 -26 3 47 -24 34 51 -27 38 16 -23 2 28 139 0 0 -24 50 55 11 3 25 21 251 -26 -25 35 31 -24 6 33 -27 10 3 -22 34 9 140 0 0 -24 22 30 11 3 27 20 251 -27 -25 7 7 -23 38 8 -26 41 41 -22 5 42 141 0 0 -23 53 58 11 3 28 19 250 -28 -24 38 36 -23 9 35 -26 13 10 -21 37 8 142 0 0 -23 25 19 11 3 29 18 250 -29 -24 9 57 -22 40 56 -25 44 31 -21 8 28 143 0 0 -22 56 33 11 3 30 17 249 -30 -23 41 11 -22 12 10 -25 15 46 -20 39 43 144 0 0 -22 27 43 11 3 31 16 249 -31 -23 12 20 -21 43 20 -24 46 55 -20 10 53 145 0 0 -21 58 48 11 3 32 15 249 -32 -22 43 25 -21 14 25 -24 17 58 -19 42 0 146 0 0 -21 29 49 11 3 33 14 248 -33 -22 14 25 -20 45 27 -23 48 57 -19 13 3 147 0 0 -21 0 47 11 3 34 13 248 -34 -21 45 23 -20 16 27 -23 19 52 -18 44 4 148 0 0 -20 31 43 11 3 35 12 247 -35 -21 16 18 -19 47 24 -22 50 45 -18 15 4 149 0 0 -20 2 38 11 3 35 11 247 -36 -20 47 11 -19 18 20 -22 21 36 -17 46 3 150 0 0 -19 33 33 11 3 36 10 247 -37 -20 18 4 -18 49 16 -21 52 25 -17 17 2 151 0 0 -19 4 28 11 3 36 9 246 -38 -19 48 57 -18 20 13 -21 23 14 -16 48 3 152 0 0 -18 35 24 11 3 37 8 246 -39 -19 19 52 -17 51 11 -20 54 4 -16 19 5 153 0 0 -18 6 22 11 3 37 7 246 -40 -18 50 48 -17 22 12 -20 24 55 -15 50 10 154 0 0 -17 37 23 11 3 38 6 245 -41 -18 21 46 -16 53 15 -19 55 49 -15 21 18 155 0 0 -17 8 28 11 3 38 4 245 -42 -17 52 48 -16 24 22 -19 26 45 -14 52 31 156 0 0 -16 39 37 11 3 38 3 245 -43 -17 23 55 -15 55 34 -18 57 46 -14 23 49 157 0 0 -16 10 52 11 3 39 2 245 -44 -16 55 6 -15 26 52 -18 28 51 .. .. .. 158 0 0 -15 42 13 11 3 39 1 244 -45 -16 26 24 -14 58 16 -18 0 2 .. .. .. 159 0 0 -15 13 40 11 3 39 0 244 -46 -15 57 48 .. .. .. -17 31 19 .. .. .. Uncertainty in time = +/- 4 secs [Prediction of 2008 Oct 1.0] Data for the target star ------------------------ * name: 2UCAC 21615068 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 18 14 56.1337 DE: -25 03 22.239 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .051, .051 ) * V mag [mag]: 12.5 * B mag [mag]: 0.0 * Apparent position with proper motion RA(deg): 273.8694225969 DE(deg): -25.0548395896 * Equation of equinoxes (radians) : 0.000048454491909 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (212) Medea approx. diameter [km]: 136 approx. diameter ["]: .049 distance from Earth [AU]: 3.85900 * orbital information: orbit source: Preston date of fit: 2008 Sep 30 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 862 number of rejected observations: 99 time covered by the observations: 1902 Mar 03 - 2008 Aug 02 1 sigma uncertainty ellipse (major, minor, PA): 0.009, 0.007, 84° remarks: * orbital elements for (212) Medea : Mean anomaly = 244.06718897 deg Arg. of pericenter = 99.36876660 deg Long. of node = 313.57811395 deg Inclination = 4.26890762 deg Eccentricity = 0.10913853 Semimajor axis = 3.12056259 AU Perihelion dist = 2.77998899 AU Mag: H = 8.22, G = 0.15 Epoch of elements : MJD 54776.45900000 TDT (2008 Nov 06.459) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Nov 6 212 Medea 11h 0.8m UT 12.5 18 14 56.134-25 3 22.242UCAC 21615068 0.0 14.6 136 3.9 3.859 3.316 3.24 62.4952 -25.057 10.71 -16.16 11.0136 0.02526 -0.35373 19.77331 1.41988 0.00449 0.00000 2000 242.91235420081031.00000 99.368767313.578114 4.2689080.10913853 3.1205626 2.7799890 8.3 5.00.15 RATE 1.7879470 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.052 0.051 90 2.05 0.051 0 54740.5020081106_615068 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Oct 01, 23:53 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org