IOTA/IOTA-ES occultation update for (245) Vera / TYC 6173-00458-1 event on 2012 Sep 14, 17:46 UT Visible from S Africa Summary ------- On 2012 Sep 14 UT, the 73 km diameter asteroid (245) Vera will occult a 10.0 mag star in the constellation Libra for observers along a path across S Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 4.4 mag to 14.4 mag (the magnitude of the asteroid) for at most 2.4 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Hugh Harris, 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: 2012 Sep 14, 17:48 - 2012 Sep 14, 17:49 UT * geocentric midpoint of event [JD]: 2456185.24044167 * magnitude of target star: 10.0 * magnitude drop [mag]: 4.4 * estimated maximum duration [s]: 2.4 * Moon: 2 % sunlit, 74° distance * Sun: 57° distance * rough path description: S Africa The occultation path -------------------- * approximate projected width [km]: 73 * 1 sigma uncertainty interval [path widths]: +/- 1.06 * 1 sigma uncertainty interval [seconds]: +/- 2.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .031 +/- .026) * 1 sigma uncertainty ellipse (major, minor, PA): ( .031", .026", 92° ) * approx speed of asteroid's shadow [km/s]: 30.0610 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6173-00458-1 by 245 Vera on 2012 Sep 14 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 1 0 0 -25 31 11 17 48 11 56 276 -1 -25 51 2 -25 11 20 -26 33 8 -24 29 15 2 0 0 -25 35 53 17 48 14 55 276 -2 -25 55 43 -25 16 3 -26 37 47 -24 34 0 3 0 0 -25 40 10 17 48 16 55 275 -2 -26 0 0 -25 20 21 -26 42 2 -24 38 19 4 0 0 -25 44 2 17 48 19 54 275 -3 -26 3 51 -25 24 14 -26 45 52 -24 42 13 5 0 0 -25 47 30 17 48 22 53 274 -4 -26 7 18 -25 27 42 -26 49 18 -24 45 42 6 0 0 -25 50 33 17 48 25 52 274 -5 -26 10 21 -25 30 45 -26 52 19 -24 48 47 7 0 0 -25 53 11 17 48 27 51 273 -6 -26 12 58 -25 33 23 -26 54 56 -24 51 26 8 0 0 -25 55 24 17 48 30 50 273 -7 -26 15 11 -25 35 37 -26 57 8 -24 53 41 9 0 0 -25 57 13 17 48 32 49 272 -8 -26 16 59 -25 37 26 -26 58 55 -24 55 30 10 0 0 -25 58 36 17 48 35 48 272 -9 -26 18 23 -25 38 50 -27 0 19 -24 56 55 11 0 0 -25 59 36 17 48 37 47 272 -10 -26 19 22 -25 39 49 -27 1 17 -24 57 54 12 0 0 -26 0 10 17 48 40 46 271 -11 -26 19 56 -25 40 24 -27 1 51 -24 58 29 13 0 0 -26 0 20 17 48 42 45 271 -12 -26 20 6 -25 40 34 -27 2 1 -24 58 39 14 0 0 -26 0 5 17 48 45 45 270 -12 -26 19 51 -25 40 19 -27 1 47 -24 58 24 15 0 0 -25 59 26 17 48 47 44 270 -13 -26 19 12 -25 39 39 -27 1 8 -24 57 44 16 0 0 -25 58 22 17 48 49 43 269 -14 -26 18 8 -25 38 35 -27 0 4 -24 56 40 17 0 0 -25 56 53 17 48 52 42 269 -15 -26 16 40 -25 37 6 -26 58 36 -24 55 10 18 0 0 -25 55 0 17 48 54 41 268 -16 -26 14 47 -25 35 13 -26 56 44 -24 53 16 19 0 0 -25 52 42 17 48 56 40 268 -17 -26 12 30 -25 32 55 -26 54 27 -24 50 57 20 0 0 -25 50 0 17 48 58 39 268 -18 -26 9 48 -25 30 12 -26 51 46 -24 48 13 21 0 0 -25 46 53 17 49 0 38 267 -19 -26 6 41 -25 27 4 -26 48 41 -24 45 5 22 0 0 -25 43 21 17 49 2 37 267 -20 -26 3 10 -25 23 32 -26 45 11 -24 41 31 23 0 0 -25 39 25 17 49 4 36 266 -21 -25 59 15 -25 19 35 -26 41 17 -24 37 33 24 0 0 -25 35 4 17 49 6 35 266 -22 -25 54 55 -25 15 14 -26 36 59 -24 33 10 25 0 0 -25 30 19 17 49 8 34 265 -22 -25 50 10 -25 10 28 -26 32 16 -24 28 23 26 0 0 -25 25 9 17 49 10 34 265 -23 -25 45 1 -25 5 17 -26 27 9 -24 23 10 27 0 0 -25 19 35 17 49 12 33 264 -24 -25 39 28 -24 59 42 -26 21 37 -24 17 33 28 0 0 -25 13 36 17 49 14 32 264 -25 -25 33 30 -24 53 42 -26 15 42 -24 11 31 29 0 0 -25 7 13 17 49 16 31 264 -26 -25 27 8 -24 47 18 -26 9 21 -24 5 4 30 0 0 -25 0 25 17 49 17 30 263 -27 -25 20 21 -24 40 29 -26 2 37 -23 58 13 31 0 0 -24 53 12 17 49 19 29 263 -28 -25 13 10 -24 33 15 -25 55 28 -23 50 57 32 0 0 -24 45 36 17 49 21 28 262 -29 -25 5 34 -24 25 37 -25 47 55 -23 43 17 33 0 0 -24 37 34 17 49 22 27 262 -30 -24 57 34 -24 17 35 -25 39 58 -23 35 11 34 0 0 -24 29 8 17 49 24 26 261 -31 -24 49 10 -24 9 7 -25 31 36 -23 26 41 35 0 0 -24 20 18 17 49 25 25 261 -32 -24 40 21 -24 0 16 -25 22 50 -23 17 47 36 0 0 -24 11 4 17 49 27 24 261 -33 -24 31 8 -23 51 0 -25 13 40 -23 8 28 37 0 0 -24 1 25 17 49 28 23 260 -34 -24 21 30 -23 41 19 -25 4 6 -22 58 44 38 0 0 -23 51 21 17 49 29 22 260 -34 -24 11 28 -23 31 14 -24 54 7 -22 48 36 39 0 0 -23 40 54 17 49 31 22 259 -35 -24 1 2 -23 20 45 -24 43 45 -22 38 3 40 0 0 -23 30 2 17 49 32 21 259 -36 -23 50 12 -23 9 51 -24 32 58 -22 27 6 41 0 0 -23 18 45 17 49 33 20 259 -37 -23 38 57 -22 58 33 -24 21 47 -22 15 45 42 0 0 -23 7 5 17 49 34 19 258 -38 -23 27 18 -22 46 51 -24 10 12 -22 3 59 43 0 0 -22 55 0 17 49 35 18 258 -39 -23 15 15 -22 34 45 -23 58 12 -21 51 48 44 0 0 -22 42 31 17 49 36 17 257 -40 -23 2 49 -22 22 14 -23 45 49 -21 39 14 45 0 0 -22 29 39 17 49 37 16 257 -41 -22 49 58 -22 9 20 -23 33 2 -21 26 15 46 0 0 -22 16 22 17 49 38 15 257 -42 -22 36 43 -21 56 1 -23 19 51 -21 12 53 47 0 0 -22 2 41 17 49 39 14 256 -43 -22 23 4 -21 42 18 -23 6 17 -20 59 6 48 0 0 -21 48 36 17 49 40 13 256 -44 -22 9 1 -21 28 12 -22 52 18 -20 44 55 49 0 0 -21 34 8 17 49 41 12 256 -45 -21 54 35 -21 13 41 -22 37 56 -20 30 21 50 0 0 -21 19 16 17 49 42 11 255 -46 -21 39 45 -20 58 47 -22 23 11 -20 15 22 51 0 0 -21 4 1 17 49 42 10 255 -47 -21 24 31 -20 43 30 -22 8 2 -20 0 0 52 0 0 -20 48 22 17 49 43 9 254 -48 -21 8 55 -20 27 49 -21 52 29 -19 44 15 53 0 0 -20 32 19 17 49 43 8 254 -49 -20 52 54 -20 11 44 -21 36 33 -19 28 6 54 0 0 -20 15 54 17 49 44 7 254 -50 -20 36 31 -19 55 17 -21 20 14 -19 11 34 55 0 0 -19 59 5 17 49 44 6 253 -51 -20 19 45 -19 38 26 -21 3 33 -18 54 39 56 0 0 -19 41 54 17 49 45 5 253 -52 -20 2 35 -19 21 12 -20 46 28 -18 37 21 57 0 0 -19 24 20 17 49 45 4 253 -53 -19 45 3 -19 3 36 -20 29 0 -18 19 40 58 0 0 -19 6 23 17 49 45 3 252 -54 -19 27 9 -18 45 37 -20 11 10 -18 1 36 59 0 0 -18 48 4 17 49 45 2 252 -55 -19 8 52 -18 27 16 -19 52 58 -17 43 10 60 0 0 -18 29 22 17 49 46 1 252 -56 -18 50 13 -18 8 32 -19 34 24 -17 24 22 61 0 0 -18 10 19 17 49 46 0 251 -57 -18 31 11 -17 49 27 -19 15 27 .. .. .. Uncertainty in time = +/- 3 secs Prediction of 2012 Jul 21.0 Data for the target star ------------------------ * name: TYC 6173-00458-1 * constellation : Libra * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 15 06 44.1877 DE: -17 37 39.754 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .030, .025 ) * V mag [mag]: 10.0 * B mag [mag]: 11.6 * Apparent position with proper motion RA(deg): 226.8646310851 DE(deg): -17.6756400747 * Equation of equinoxes (radians) : 0.000067902836778 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (245) Vera approx. diameter [km]: 73 approx. diameter ["]: .025 distance from Earth [AU]: 4.01300 * orbital information: orbit source: Preston date of fit: 2012 Jul 21 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 918 number of rejected observations: 117 time covered by the observations: 1902 Feb 27 - 2012 Jun 22 1 sigma uncertainty ellipse (major, minor, PA): 0.009, 0.006, 111° remarks: * orbital elements for (245) Vera : Mean anomaly = 226.23628499 deg Arg. of pericenter = 328.82569884 deg Long. of node = 61.41547648 deg Inclination = 5.15975179 deg Eccentricity = 0.19402949 Semimajor axis = 3.10106718 AU Perihelion dist = 2.49936868 AU Mag: H = 7.66, G = 0.15 Epoch of elements : MJD 56184.74000000 TDT (2012 Sep 14.740) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 14 245 Vera 17h 46.2m UT 10.0 15 6 44.188-17 37 39.75TYC 6173-00458-1 11.6 14.4 73 2.4 4.013 2.471 -11.63 -33.9798 -17.624 -87.73 3.05 17.7706 -0.00075 -0.01220 16.11625 -5.30608 0.00473 -0.00135 2000 225.3807942012 910.00000328.825699 61.415476 5.1597520.19402949 3.1010672 2.4993687 7.8 5.00.15 RATE 1.8048340 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.031 0.026 92 2.06 0.027 0 0-3-4 056129.0020120914_0458-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Jul 22, 03:48 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org