IOTA/IOTA-ES occultation update for (14) Irene / 2UCAC 40652494 event on 2008 May 10, 19:54 UT Visible from Europe Summary ------- On 2008 May 10 UT, the 182 km diameter asteroid (14) Irene will occult a 12.5 mag star in the constellation Taurus for observers along a path across Europe. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.4 mag to 11.6 mag (the magnitude of the asteroid) for at most 4.4 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: 86 * date and approx. time of event: 2008 May 10, 19:56 - 2008 May 10, 19:56 UT * midpoint of event [JD]: 2454597.32965 * magnitude of target star: 12.5 * magnitude drop [mag]: 0.4 * estimated maximum duration [s]: 4.4 * Moon: 36 % sunlit, 36° distance * Sun: 37° distance * rough path description: Europe The occultation path -------------------- * approximate projected width [km]: 224 * 1 sigma uncertainty interval [path widths]: +/- 0.59 * 1 sigma uncertainty interval [seconds]: +/- 2.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .048 +/- .047) * 1 sigma uncertainty ellipse (major, minor, PA): ( .048", .047", 90° ) * approx speed of asteroid's shadow [km/s]: 41.0310 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 40652494 by 14 Irene on 2008 May 10 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 - 6 0 0 51 17 29 19 56 23 29 275 0 50 8 49 52 27 17 48 49 8 53 51 14 - 5 0 0 50 56 33 19 56 24 28 276 -1 49 47 42 52 6 32 48 27 49 53 30 43 - 4 0 0 50 35 14 19 56 26 27 277 -2 49 26 12 51 45 24 48 6 7 53 9 48 - 3 0 0 50 13 31 19 56 27 27 278 -2 49 4 20 51 23 52 47 44 4 52 48 30 - 2 0 0 49 51 26 19 56 28 26 279 -3 48 42 5 51 1 58 47 21 38 52 26 49 - 1 0 0 49 28 59 19 56 29 25 280 -4 48 19 28 50 39 40 46 58 50 52 4 44 0 0 0 49 6 9 19 56 30 25 281 -5 47 56 28 50 17 0 46 35 40 51 42 16 1 0 0 48 42 56 19 56 31 24 282 -5 47 33 7 49 53 57 46 12 8 51 19 25 2 0 0 48 19 22 19 56 32 23 283 -6 47 9 24 49 30 32 45 48 15 50 56 11 3 0 0 47 55 26 19 56 33 22 283 -7 46 45 19 49 6 44 45 24 2 50 32 34 4 0 0 47 31 8 19 56 34 22 284 -8 46 20 54 48 42 35 44 59 27 50 8 35 5 0 0 47 6 29 19 56 35 21 285 -9 45 56 7 48 18 4 44 34 32 49 44 14 6 0 0 46 41 29 19 56 36 20 286 -9 45 31 0 47 53 11 44 9 17 49 19 31 7 0 0 46 16 9 19 56 37 19 287 -10 45 5 33 47 27 58 43 43 43 48 54 27 8 0 0 45 50 28 19 56 38 19 287 -11 44 39 46 47 2 24 43 17 49 48 29 1 9 0 0 45 24 28 19 56 39 18 288 -12 44 13 41 46 36 30 42 51 37 48 3 15 10 0 0 44 58 9 19 56 39 17 289 -13 43 47 16 46 10 17 42 25 6 47 37 8 11 0 0 44 31 31 19 56 40 16 290 -13 43 20 33 45 43 44 41 58 18 47 10 42 12 0 0 44 4 35 19 56 41 15 291 -14 42 53 33 45 16 53 41 31 13 46 43 56 13 0 0 43 37 21 19 56 42 14 291 -15 42 26 15 44 49 43 41 3 51 46 16 52 14 0 0 43 9 51 19 56 43 14 292 -16 41 58 41 44 22 16 40 36 13 45 49 29 15 0 0 42 42 4 19 56 43 13 293 -17 41 30 51 43 54 32 40 8 20 45 21 49 16 0 0 42 14 1 19 56 44 12 293 -18 41 2 46 43 26 32 39 40 12 44 53 52 17 0 0 41 45 43 19 56 44 11 294 -18 40 34 27 42 58 16 39 11 51 44 25 39 18 0 0 41 17 11 19 56 45 10 295 -19 40 5 53 42 29 45 38 43 16 43 57 10 19 0 0 40 48 25 19 56 45 9 295 -20 39 37 6 42 1 0 38 14 28 43 28 26 20 0 0 40 19 27 19 56 46 8 296 -21 39 8 8 41 32 2 37 45 29 42 59 28 21 0 0 39 50 16 19 56 46 7 297 -22 38 38 57 41 2 51 37 16 19 42 30 16 22 0 0 39 20 54 19 56 47 7 297 -23 38 9 36 40 33 28 36 46 59 42 0 53 23 0 0 38 51 22 19 56 47 6 298 -24 37 40 5 40 3 54 36 17 29 41 31 17 24 0 0 38 21 40 19 56 47 5 299 -25 37 10 25 39 34 11 .. .. .. 41 1 31 25 0 0 37 51 49 19 56 48 4 299 -25 36 40 37 39 4 17 .. .. .. 40 31 35 26 0 0 37 21 51 19 56 48 3 300 -26 36 10 41 38 34 16 .. .. .. 40 1 30 27 0 0 36 51 46 19 56 48 2 301 -27 35 40 40 38 4 7 .. .. .. 39 31 16 28 0 0 36 21 34 19 56 48 1 301 -28 35 10 32 37 33 52 .. .. .. 39 0 56 29 0 0 35 51 18 19 56 48 0 302 -29 .. .. .. 37 3 31 .. .. .. 38 30 30 Uncertainty in time = +/- 3 secs [Prediction of 2008 Mar 31.0] Data for the target star ------------------------ * name: 2UCAC 40652494 * constellation : Taurus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 05 48 57.5501 DE: +25 18 09.064 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .048, .046 ) * V mag [mag]: 12.5 * B mag [mag]: 0.0 * Apparent position with proper motion RA(deg): 87.3667053922 DE(deg): 25.3067891181 * Equation of equinoxes (radians) : 0.000041094185667 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (14) Irene approx. diameter [km]: 182 approx. diameter ["]: .079 distance from Earth [AU]: 3.17400 * orbital information: orbit source: Preston date of fit: 2008 Mar 28 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1544 number of rejected observations: 186 time covered by the observations: 1907 Nov 30 - 2008 Feb 11 1 sigma uncertainty ellipse (major, minor, PA): 0.007, 0.005, 80° remarks: * orbital elements for (14) Irene : Mean anomaly = 297.86050706 deg Arg. of pericenter = 96.30657002 deg Long. of node = 86.45761263 deg Inclination = 9.10725115 deg Eccentricity = 0.16769322 Semimajor axis = 2.58579485 AU Perihelion dist = 2.15217459 AU Mag: H = 6.32, G = 0.15 Epoch of elements : MJD 54596.83000000 TDT (2008 May 10.830) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 10 14 Irene 19h 54.7m UT 12.5 5 48 57.550 25 18 9.062UCAC 40652494 0.0 11.6 182 4.4 3.174 4.717 5.08 -80.4182 25.302 -119.57 17.88 19.9116 -0.04634 0.57977 23.08612 1.83663 0.00329 0.00021 2000 296.2415562008 5 4.00000 96.306570 86.457613 9.1072510.16769322 2.5857949 2.1521746 6.3 5.00.15 RATE 2.3703530 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.048 0.047 90 1.59 0.047 0 54556.5020080510_652494 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 31, 04:30 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org