IOTA/IOTA-ES occultation update for (440) Theodora / TYC 1401-01744-1 event on 2008 May 08, 23:21 UT Visible from Chile, Argentina Summary ------- On 2008 May 08 UT, the 16 km diameter asteroid (440) Theodora will occult a 9.6 mag star in the constellation Cancer for observers along a path across Chile, Argentina. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.1 mag to 15.7 mag (the magnitude of the asteroid) for at most 0.7 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: 31 * date and approx. time of event: 2008 May 08, 23:21 - 2008 May 08, 23:25 UT * magnitude of target star: 9.6 * magnitude drop [mag]: 6.1 * estimated maximum duration [s]: 0.7 * Moon: 17 % sunlit, 39° distance * Sun: 86° distance * rough path description: Chile, Argentina The occultation path -------------------- * approximate projected width [km]: 20 * 1 sigma uncertainty interval [path widths]: +/- 2.16 * 1 sigma uncertainty interval [seconds]: +/- 1.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .031 +/- .026) * 1 sigma uncertainty ellipse (major, minor, PA): ( .031", .026", 101° ) * approx speed of asteroid's shadow [km/s]: 21.1742 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1401-01744-1 by 440 Theodora on 2008 May 8 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 - 88 0 0 -23 14 46 23 21 55 51 11 -1 -23 20 39 -23 8 54 -23 46 11 -22 43 36 - 87 0 0 -23 34 19 23 22 0 51 10 -2 -23 40 13 -23 28 26 -24 5 48 -23 3 5 - 86 0 0 -23 54 14 23 22 5 51 8 -3 -24 0 9 -23 48 20 -24 25 47 -23 22 55 - 85 0 0 -24 14 31 23 22 11 51 6 -4 -24 20 27 -24 8 36 -24 46 9 -23 43 8 - 84 0 0 -24 35 10 23 22 16 50 5 -5 -24 41 6 -24 29 14 -25 6 52 -24 3 43 - 83 0 0 -24 56 10 23 22 21 50 3 -6 -25 2 7 -24 50 13 -25 27 56 -24 24 38 - 82 0 0 -25 17 30 23 22 26 50 2 -7 -25 23 28 -25 11 33 -25 49 21 -24 45 54 - 81 0 0 -25 39 11 23 22 31 49 0 -8 -25 45 10 -25 33 12 -26 11 6 -25 7 30 - 80 0 0 -26 1 10 23 22 36 49 359 -9 -26 7 10 -25 55 11 -26 33 11 -25 29 25 - 79 0 0 -26 23 29 23 22 41 49 357 -10 -26 29 30 -26 17 29 -26 55 34 -25 51 40 - 78 0 0 -26 46 6 23 22 46 48 356 -11 -26 52 7 -26 40 5 -27 18 15 -26 14 12 - 77 0 0 -27 9 0 23 22 51 48 354 -12 -27 15 2 -27 2 58 -27 41 14 -26 37 2 - 76 0 0 -27 32 11 23 22 56 47 353 -13 -27 38 14 -27 26 8 -28 4 29 -27 0 8 - 75 0 0 -27 55 38 23 23 1 47 351 -14 -28 1 42 -27 49 35 -28 28 1 -27 23 31 - 74 0 0 -28 19 21 23 23 5 46 350 -15 -28 25 26 -28 13 17 -28 51 48 -27 47 10 - 73 0 0 -28 43 19 23 23 10 46 349 -16 -28 49 24 -28 37 14 -29 15 50 -28 11 4 - 72 0 0 -29 7 31 23 23 15 45 347 -17 -29 13 37 -29 1 25 -29 40 6 -28 35 11 - 71 0 0 -29 31 56 23 23 20 44 346 -18 -29 38 3 -29 25 49 -30 4 36 -28 59 32 - 70 0 0 -29 56 34 23 23 24 44 345 -18 -30 2 42 -29 50 27 -30 29 18 -29 24 6 - 69 0 0 -30 21 24 23 23 29 43 344 -19 -30 27 32 -30 15 16 -30 54 12 -29 48 52 - 68 0 0 -30 46 25 23 23 33 43 343 -20 -30 52 34 -30 40 16 -31 19 17 -30 13 49 - 67 0 0 -31 11 36 23 23 37 42 341 -21 -31 17 46 -31 5 27 -31 44 32 -30 38 57 - 66 0 0 -31 36 57 23 23 42 41 340 -22 -31 43 8 -31 30 47 -32 9 57 -31 4 14 - 65 0 0 -32 2 27 23 23 46 40 339 -23 -32 8 39 -31 56 16 -32 35 31 -31 29 40 - 64 0 0 -32 28 5 23 23 50 40 338 -24 -32 34 17 -32 21 53 -33 1 12 -31 55 14 - 63 0 0 -32 53 50 23 23 54 39 337 -25 -33 0 3 -32 47 38 -33 27 1 -32 20 56 - 62 0 0 -33 19 41 23 23 58 38 336 -26 -33 25 55 -33 13 29 -33 52 56 -32 46 44 - 61 0 0 -33 45 39 23 24 2 38 335 -27 -33 51 53 -33 39 25 -34 18 56 -33 12 38 - 60 0 0 -34 11 41 23 24 6 37 334 -28 -34 17 55 -34 5 26 -34 45 1 -33 38 37 - 59 0 0 -34 37 46 23 24 10 36 333 -28 -34 44 2 -34 31 32 -35 11 10 -34 4 40 - 58 0 0 -35 3 55 23 24 13 35 332 -29 -35 10 11 -34 57 40 -35 37 22 -34 30 46 - 57 0 0 -35 30 7 23 24 17 35 331 -30 -35 36 23 -35 23 51 -36 3 36 -34 56 55 - 56 0 0 -35 56 20 23 24 21 34 330 -31 -36 2 37 -35 50 4 -36 29 52 -35 23 5 - 55 0 0 -36 22 33 23 24 24 33 329 -32 -36 28 51 -36 16 17 -36 56 8 -35 49 17 - 54 0 0 -36 48 47 23 24 27 32 328 -32 -36 55 5 -36 42 30 -37 22 23 -36 15 28 - 53 0 0 -37 15 0 23 24 31 31 327 -33 -37 21 18 -37 8 42 -37 48 38 -36 41 39 - 52 0 0 -37 41 11 23 24 34 31 326 -34 -37 47 29 -37 34 53 -38 14 51 -37 7 48 - 51 0 0 -38 7 19 23 24 37 30 326 -35 -38 13 38 -38 1 1 -38 41 1 -37 33 55 - 50 0 0 -38 33 25 23 24 40 29 325 -36 -38 39 44 -38 27 6 -39 7 8 -37 59 59 - 49 0 0 -38 59 26 23 24 43 28 324 -36 -39 5 45 -38 53 7 -39 33 11 -38 25 58 - 48 0 0 -39 25 22 23 24 46 27 323 -37 -39 31 42 -39 19 4 -39 59 9 -38 51 54 - 47 0 0 -39 51 13 23 24 48 26 322 -38 -39 57 33 -39 44 54 -40 25 1 -39 17 44 - 46 0 0 -40 16 58 23 24 51 26 321 -38 -40 23 18 -40 10 39 -40 50 47 -39 43 28 - 45 0 0 -40 42 36 23 24 53 25 321 -39 -40 48 56 -40 36 17 -41 16 25 -40 9 5 - 44 0 0 -41 8 6 23 24 56 24 320 -40 -41 14 27 -41 1 47 -41 41 56 -40 34 35 - 43 0 0 -41 33 28 23 24 58 23 319 -40 -41 39 49 -41 27 9 -42 7 18 -40 59 57 - 42 0 0 -41 58 41 23 25 0 22 318 -41 -42 5 2 -41 52 22 -42 32 31 -41 25 10 - 41 0 0 -42 23 45 23 25 3 22 317 -42 -42 30 5 -42 17 25 -42 57 34 -41 50 13 - 40 0 0 -42 48 38 23 25 5 21 317 -42 -42 54 58 -42 42 19 -43 22 27 -42 15 7 - 39 0 0 -43 13 20 23 25 7 20 316 -43 -43 19 40 -43 7 1 -43 47 9 -42 39 50 - 38 0 0 -43 37 51 23 25 8 19 315 -43 -43 44 11 -43 31 32 -44 11 39 -43 4 21 - 37 0 0 -44 2 10 23 25 10 18 314 -44 -44 8 30 -43 55 51 -44 35 57 -43 28 41 - 36 0 0 -44 26 17 23 25 12 18 314 -44 -44 32 36 -44 19 58 -45 0 3 -43 52 48 - 35 0 0 -44 50 10 23 25 14 17 313 -45 -44 56 29 -44 43 52 -45 23 55 -44 16 43 - 34 0 0 -45 13 50 23 25 15 16 312 -45 -45 20 9 -45 7 32 -45 47 34 -44 40 24 - 33 0 0 -45 37 16 23 25 17 15 311 -46 -45 43 35 -45 30 58 -46 10 58 -45 3 52 - 32 0 0 -46 0 27 23 25 18 14 310 -46 -46 6 46 -45 54 10 -46 34 7 -45 27 5 - 31 0 0 -46 23 24 23 25 19 14 310 -47 -46 29 42 -46 17 7 -46 57 2 -45 50 3 - 30 0 0 -46 46 5 23 25 20 13 309 -47 -46 52 23 -46 39 48 -47 19 41 -46 12 47 - 29 0 0 -47 8 31 23 25 22 12 308 -48 -47 14 48 -47 2 14 -47 42 5 -46 35 15 - 28 0 0 -47 30 40 23 25 23 11 307 -48 -47 36 57 -47 24 24 -48 4 12 -46 57 27 - 27 0 0 -47 52 34 23 25 24 11 307 -48 -47 58 50 -47 46 18 -48 26 2 -47 19 22 - 26 0 0 -48 14 10 23 25 24 10 306 -49 -48 20 26 -48 7 55 -48 47 36 -47 41 1 - 25 0 0 -48 35 30 23 25 25 9 305 -49 -48 41 45 -48 29 15 -49 8 53 -48 2 24 - 24 0 0 -48 56 32 23 25 26 8 304 -49 -49 2 47 -48 50 18 -49 29 52 -48 23 29 - 23 0 0 -49 17 17 23 25 27 8 304 -50 -49 23 31 -49 11 3 -49 50 34 -48 44 17 - 22 0 0 -49 37 44 23 25 27 7 303 -50 -49 43 57 -49 31 31 -50 10 58 -49 4 47 - 21 0 0 -49 57 53 23 25 28 6 302 -50 -50 4 6 -49 51 41 -50 31 3 -49 25 0 - 20 0 0 -50 17 44 23 25 28 5 301 -50 -50 23 56 -50 11 32 -50 50 51 -49 44 54 - 19 0 0 -50 37 17 23 25 29 5 301 -51 -50 43 28 -50 31 6 -51 10 20 -50 4 30 - 18 0 0 -50 56 31 23 25 29 4 300 -51 -51 2 42 -50 50 21 -51 29 30 -50 23 48 - 17 0 0 -51 15 27 23 25 29 3 299 -51 -51 21 37 -51 9 17 -51 48 22 -50 42 48 - 16 0 0 -51 34 4 23 25 30 3 298 -51 -51 40 13 -51 27 55 -52 6 55 -51 1 28 - 15 0 0 -51 52 22 23 25 30 2 297 -51 -51 58 30 -51 46 14 -52 25 10 .. .. .. - 14 0 0 -52 10 21 23 25 30 1 297 -51 -52 16 29 -52 4 14 -52 43 5 .. .. .. - 13 0 0 -52 28 1 23 25 30 1 296 -51 -52 34 8 -52 21 55 -53 0 41 .. .. .. Uncertainty in time = +/- 2 secs [Prediction of 2008 Apr 23.0] Data for the target star ------------------------ * name: TYC 1401-01744-1 * constellation : Cancer * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 09 06 50.5720 DE: +15 06 21.484 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .021, .021 ) * V mag [mag]: 9.6 * B mag [mag]: 10.1 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (440) Theodora approx. diameter [km]: 16 approx. diameter ["]: .012 distance from Earth [AU]: 1.85600 * orbital information: orbit source: Preston date of fit: 2008 Apr 22 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 920 number of rejected observations: 61 time covered by the observations: 1900 Mar 29 - 2008 Apr 08 1 sigma uncertainty ellipse (major, minor, PA): 0.023, 0.015, 109° remarks: * orbital elements for (440) Theodora : Mean anomaly = 43.78933953 deg Arg. of pericenter = 178.59095130 deg Long. of node = 292.26824879 deg Inclination = 1.59877023 deg Eccentricity = 0.10796988 Semimajor axis = 2.21010663 AU Perihelion dist = 1.97148168 AU Mag: H = 11.49, G = 0.15 Epoch of elements : MJD 54594.97300000 TDT (2008 May 08.973) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 8 440 Theodora 23h 21.6m UT 9.6 9 6 50.572 15 6 21.48TYC 1401-01744-1 10.1 15.7 16 0.7 1.856 3.746 -16.18 -80.8381 15.110 -171.28 17.40 23.3597 -0.17923 -0.59682 11.45302 -3.41495 0.00499 -0.00152 2000 42.2975672008 5 4.00000178.590951292.268249 1.5987700.10796988 2.2101066 1.971481711.5 5.00.15 RATE 2.9997440 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.031 0.026 101 3.16 0.026 0 54579.5020080508_1744-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 23, 04:14 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org