IOTA/IOTA-ES occultation update for (18) Melpomene / UCAC2 32475087 event on 2009 Jul 06, 05:16 UT Visible from Summary ------- On 2009 Jul 06 UT, the 141 km diameter asteroid (18) Melpomene will occult a 11.9 mag star in the constellation Cetus for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 0.2 mag to 10.0 mag (the magnitude of the asteroid) for at most 7.6 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: 99 * date and approx. time of event: 2009 Jul 06, 05:12 - 2009 Jul 06, 05:17 UT * magnitude of target star: 11.9 * magnitude drop [mag]: 0.2 * estimated maximum duration [s]: 7.6 * Moon: 99 % sunlit, 97° distance * Sun: 96° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 186 * 1 sigma uncertainty interval [path widths]: +/- 0.20 * 1 sigma uncertainty interval [seconds]: +/- 1.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .030 +/- .026) * 1 sigma uncertainty ellipse (major, minor, PA): ( .030", .026", 87° ) * approx speed of asteroid's shadow [km/s]: 18.4892 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC2 32475087 by 18 Melpomene on 2009 Jul 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 - 81 0 0 -50 15 56 5 12 9 0 86 -62 -51 6 44 -49 25 47 -51 27 14 -49 5 53 - 80 0 0 -50 13 27 5 12 9 1 85 -62 -51 4 15 -49 23 17 -51 24 46 -49 3 23 - 79 0 0 -50 10 49 5 12 9 2 84 -62 -51 1 38 -49 20 38 -51 22 9 -49 0 45 - 78 0 0 -50 8 2 5 12 10 2 84 -62 -50 58 52 -49 17 51 -51 19 23 -48 57 57 - 77 0 0 -50 5 7 5 12 10 3 83 -63 -50 55 57 -49 14 55 -51 16 29 -48 55 1 - 76 0 0 -50 2 3 5 12 10 4 82 -63 -50 52 54 -49 11 50 -51 13 26 -48 51 56 - 75 0 0 -49 58 50 5 12 10 4 81 -63 -50 49 42 -49 8 37 -51 10 14 -48 48 42 - 74 0 0 -49 55 29 5 12 11 5 81 -63 -50 46 22 -49 5 15 -51 6 54 -48 45 19 - 73 0 0 -49 51 59 5 12 11 6 80 -63 -50 42 53 -49 1 44 -51 3 26 -48 41 48 - 72 0 0 -49 48 21 5 12 12 6 79 -63 -50 39 15 -48 58 4 -50 59 48 -48 38 8 - 71 0 0 -49 44 33 5 12 12 7 78 -63 -50 35 29 -48 54 16 -50 56 3 -48 34 20 - 70 0 0 -49 40 38 5 12 13 8 78 -62 -50 31 34 -48 50 20 -50 52 8 -48 30 23 - 69 0 0 -49 36 33 5 12 14 8 77 -62 -50 27 31 -48 46 14 -50 48 6 -48 26 17 - 68 0 0 -49 32 21 5 12 15 9 76 -62 -50 23 20 -48 42 1 -50 43 54 -48 22 3 - 67 0 0 -49 27 59 5 12 15 10 75 -62 -50 18 59 -48 37 38 -50 39 35 -48 17 40 - 66 0 0 -49 23 30 5 12 16 10 74 -62 -50 14 31 -48 33 8 -50 35 7 -48 13 9 - 65 0 0 -49 18 52 5 12 17 11 74 -62 -50 9 54 -48 28 28 -50 30 30 -48 8 29 - 64 0 0 -49 14 5 5 12 18 11 73 -62 -50 5 9 -48 23 41 -50 25 45 -48 3 41 - 63 0 0 -49 9 10 5 12 19 12 72 -61 -50 0 15 -48 18 45 -50 20 52 -47 58 45 - 62 0 0 -49 4 7 5 12 21 13 71 -61 -49 55 13 -48 13 40 -50 15 51 -47 53 40 - 61 0 0 -48 58 56 5 12 22 13 71 -61 -49 50 3 -48 8 28 -50 10 41 -47 48 27 - 60 0 0 -48 53 36 5 12 23 14 70 -61 -49 44 44 -48 3 7 -50 5 23 -47 43 6 - 59 0 0 -48 48 8 5 12 24 15 69 -60 -49 39 18 -47 57 38 -49 59 57 -47 37 36 - 58 0 0 -48 42 32 5 12 26 15 68 -60 -49 33 43 -47 52 0 -49 54 23 -47 31 58 - 57 0 0 -48 36 48 5 12 27 16 67 -60 -49 28 0 -47 46 15 -49 48 41 -47 26 12 - 56 0 0 -48 30 56 5 12 29 17 67 -59 -49 22 9 -47 40 21 -49 42 50 -47 20 18 - 55 0 0 -48 24 56 5 12 30 17 66 -59 -49 16 11 -47 34 20 -49 36 52 -47 14 16 - 54 0 0 -48 18 48 5 12 32 18 65 -59 -49 10 4 -47 28 11 -49 30 46 -47 8 6 - 53 0 0 -48 12 32 5 12 34 19 64 -58 -49 3 49 -47 21 53 -49 24 32 -47 1 49 - 52 0 0 -48 6 8 5 12 35 19 63 -58 -48 57 27 -47 15 28 -49 18 10 -46 55 23 - 51 0 0 -47 59 36 5 12 37 20 63 -57 -48 50 57 -47 8 55 -49 11 41 -46 48 49 - 50 0 0 -47 52 57 5 12 39 21 62 -57 -48 44 19 -47 2 15 -49 5 3 -46 42 8 - 49 0 0 -47 46 10 5 12 41 21 61 -56 -48 37 33 -46 55 26 -48 58 18 -46 35 19 - 48 0 0 -47 39 16 5 12 43 22 60 -56 -48 30 40 -46 48 30 -48 51 26 -46 28 23 - 47 0 0 -47 32 14 5 12 45 23 59 -55 -48 23 40 -46 41 27 -48 44 26 -46 21 19 - 46 0 0 -47 25 4 5 12 47 23 58 -55 -48 16 32 -46 34 17 -48 37 19 -46 14 8 - 45 0 0 -47 17 48 5 12 49 24 58 -54 -48 9 17 -46 26 58 -48 30 4 -46 6 50 - 44 0 0 -47 10 24 5 12 52 24 57 -54 -48 1 54 -46 19 33 -48 22 42 -45 59 24 - 43 0 0 -47 2 53 5 12 54 25 56 -53 -47 54 24 -46 12 1 -48 15 13 -45 51 51 - 42 0 0 -46 55 14 5 12 56 26 55 -53 -47 46 48 -46 4 21 -48 7 37 -45 44 11 - 41 0 0 -46 47 29 5 12 59 26 54 -52 -47 39 4 -45 56 35 -47 59 53 -45 36 24 - 40 0 0 -46 39 37 5 13 1 27 53 -52 -47 31 13 -45 48 42 -47 52 3 -45 28 30 - 39 0 0 -46 31 39 5 13 4 28 52 -51 -47 23 16 -45 40 42 -47 44 7 -45 20 30 - 38 0 0 -46 23 33 5 13 7 28 51 -51 -47 15 12 -45 32 35 -47 36 3 -45 12 22 - 37 0 0 -46 15 21 5 13 9 29 50 -50 -47 7 1 -45 24 22 -47 27 53 -45 4 9 - 36 0 0 -46 7 3 5 13 12 30 49 -49 -46 58 44 -45 16 2 -47 19 36 -44 55 48 - 35 0 0 -45 58 38 5 13 15 30 49 -49 -46 50 20 -45 7 36 -47 11 13 -44 47 22 - 34 0 0 -45 50 7 5 13 18 31 48 -48 -46 41 51 -44 59 4 -47 2 44 -44 38 49 - 33 0 0 -45 41 30 5 13 21 31 47 -48 -46 33 15 -44 50 25 -46 54 9 -44 30 10 - 32 0 0 -45 32 47 5 13 24 32 46 -47 -46 24 33 -44 41 41 -46 45 27 -44 21 26 - 31 0 0 -45 23 58 5 13 27 33 45 -46 -46 15 45 -44 32 51 -46 36 40 -44 12 35 - 30 0 0 -45 15 3 5 13 30 33 44 -46 -46 6 51 -44 23 55 -46 27 47 -44 3 39 - 29 0 0 -45 6 3 5 13 33 34 43 -45 -45 57 52 -44 14 54 -46 18 48 -43 54 37 - 28 0 0 -44 56 57 5 13 37 34 42 -44 -45 48 48 -44 5 47 -46 9 44 -43 45 30 - 27 0 0 -44 47 46 5 13 40 35 41 -44 -45 39 38 -43 56 35 -46 0 34 -43 36 17 - 26 0 0 -44 38 30 5 13 43 36 40 -43 -45 30 22 -43 47 17 -45 51 19 -43 26 59 - 25 0 0 -44 29 8 5 13 47 36 39 -42 -45 21 2 -43 37 55 -45 42 0 -43 17 37 - 24 0 0 -44 19 42 5 13 50 37 38 -42 -45 11 37 -43 28 28 -45 32 35 -43 8 9 - 23 0 0 -44 10 11 5 13 54 37 37 -41 -45 2 7 -43 18 56 -45 23 5 -42 58 37 - 22 0 0 -44 0 36 5 13 58 38 35 -40 -44 52 32 -43 9 20 -45 13 31 -42 49 1 - 21 0 0 -43 50 56 5 14 1 38 34 -39 -44 42 54 -42 59 40 -45 3 53 -42 39 20 - 20 0 0 -43 41 12 5 14 5 39 33 -39 -44 33 10 -42 49 55 -44 54 10 -42 29 35 - 19 0 0 -43 31 24 5 14 9 39 32 -38 -44 23 23 -42 40 6 -44 44 23 -42 19 46 - 18 0 0 -43 21 32 5 14 13 40 31 -37 -44 13 32 -42 30 13 -44 34 32 -42 9 53 - 17 0 0 -43 11 36 5 14 17 41 30 -37 -44 3 37 -42 20 17 -44 24 37 -41 59 56 - 16 0 0 -43 1 37 5 14 21 41 29 -36 -43 53 38 -42 10 17 -44 14 39 -41 49 56 - 15 0 0 -42 51 35 5 14 25 42 27 -35 -43 43 37 -42 0 14 -44 4 37 -41 39 53 - 14 0 0 -42 41 29 5 14 29 42 26 -34 -43 33 31 -41 50 8 -43 54 32 -41 29 47 - 13 0 0 -42 31 21 5 14 33 42 25 -34 -43 23 23 -41 39 59 -43 44 24 -41 19 37 - 12 0 0 -42 21 9 5 14 37 43 24 -33 -43 13 12 -41 29 47 -43 34 14 -41 9 26 - 11 0 0 -42 10 55 5 14 41 43 22 -32 -43 2 59 -41 19 33 -43 24 0 -40 59 11 - 10 0 0 -42 0 39 5 14 45 44 21 -31 -42 52 43 -41 9 16 -43 13 45 -40 48 54 - 9 0 0 -41 50 21 5 14 50 44 20 -31 -42 42 25 -40 58 58 -43 3 27 -40 38 36 - 8 0 0 -41 40 0 5 14 54 45 18 -30 -42 32 5 -40 48 37 -42 53 7 -40 28 15 - 7 0 0 -41 29 38 5 14 58 45 17 -29 -42 21 43 -40 38 15 -42 42 45 -40 17 53 - 6 0 0 -41 19 15 5 15 3 45 16 -28 -42 11 19 -40 27 51 -42 32 21 -40 7 29 - 5 0 0 -41 8 50 5 15 7 46 14 -27 -42 0 55 -40 17 26 -42 21 57 -39 57 4 - 4 0 0 -40 58 24 5 15 12 46 13 -27 -41 50 29 -40 7 0 -42 11 31 -39 46 38 - 3 0 0 -40 47 57 5 15 16 47 11 -26 -41 40 2 -39 56 33 -42 1 4 -39 36 11 - 2 0 0 -40 37 29 5 15 21 47 10 -25 -41 29 34 -39 46 6 -41 50 36 -39 25 43 - 1 0 0 -40 27 1 5 15 26 47 9 -24 -41 19 6 -39 35 38 -41 40 8 -39 15 15 0 0 0 -40 16 33 5 15 30 47 7 -23 -41 8 37 -39 25 9 -41 29 39 -39 4 47 1 0 0 -40 6 5 5 15 35 48 6 -23 -40 58 9 -39 14 41 -41 19 11 -38 54 19 2 0 0 -39 55 37 5 15 40 48 4 -22 -40 47 41 -39 4 14 -41 8 42 -38 43 52 3 0 0 -39 45 9 5 15 44 48 3 -21 -40 37 13 -38 53 46 -40 58 14 -38 33 24 4 0 0 -39 34 42 5 15 49 48 1 -20 -40 26 46 -38 43 20 -40 47 47 -38 22 58 5 0 0 -39 24 16 5 15 54 48 360 -19 -40 16 19 -38 32 54 -40 37 21 -38 12 33 6 0 0 -39 13 52 5 15 59 49 358 -19 -40 5 54 -38 22 30 -40 26 55 -38 2 9 7 0 0 -39 3 28 5 16 4 49 356 -18 -39 55 30 -38 12 7 -40 16 31 -37 51 46 8 0 0 -38 53 7 5 16 9 49 355 -17 -39 45 8 -38 1 46 -40 6 9 -37 41 25 9 0 0 -38 42 47 5 16 14 49 353 -16 -39 34 48 -37 51 27 -39 55 48 -37 31 6 10 0 0 -38 32 29 5 16 18 49 352 -15 -39 24 29 -37 41 10 -39 45 29 -37 20 49 11 0 0 -38 22 14 5 16 23 49 350 -15 -39 14 13 -37 30 55 -39 35 13 -37 10 35 12 0 0 -38 12 1 5 16 28 49 349 -14 -39 4 0 -37 20 43 -39 24 59 -37 0 23 13 0 0 -38 1 51 5 16 33 49 347 -13 -38 53 49 -37 10 34 -39 14 48 -36 50 14 14 0 0 -37 51 44 5 16 38 49 345 -12 -38 43 41 -37 0 28 -39 4 40 -36 40 8 15 0 0 -37 41 40 5 16 43 49 344 -11 -38 33 37 -36 50 25 -38 54 35 -36 30 5 16 0 0 -37 31 40 5 16 48 49 342 -11 -38 23 36 -36 40 25 -38 44 34 -36 20 6 17 0 0 -37 21 44 5 16 53 49 341 -10 -38 13 38 -36 30 30 -38 34 36 -36 10 11 18 0 0 -37 11 51 5 16 58 49 339 -9 -38 3 45 -36 20 39 -38 24 42 -36 0 20 19 0 0 -37 2 3 5 17 3 49 338 -8 -37 53 56 -36 10 51 -38 14 53 -35 50 33 20 0 0 -36 52 20 5 17 8 48 336 -7 -37 44 11 -36 1 9 -38 5 8 -35 40 51 21 0 0 -36 42 41 5 17 13 48 335 -6 -37 34 31 -35 51 31 -37 55 27 -35 31 13 22 0 0 -36 33 6 5 17 18 48 333 -6 -37 24 56 -35 41 58 -37 45 51 -35 21 41 23 0 0 -36 23 37 5 17 23 48 332 -5 -37 15 26 -35 32 30 -37 36 21 -35 12 13 24 0 0 -36 14 14 5 17 28 47 330 -4 -37 6 1 -35 23 7 -37 26 56 -35 2 51 25 0 0 -36 4 56 5 17 33 47 329 -3 -36 56 42 -35 13 50 -37 17 36 -34 53 35 26 0 0 -35 55 44 5 17 38 47 327 -2 -36 47 28 -35 4 39 -37 8 22 -34 44 24 27 0 0 -35 46 37 5 17 42 47 326 -2 -36 38 21 -34 55 34 -36 59 14 -34 35 20 28 0 0 -35 37 37 5 17 47 46 324 -1 -36 29 20 -34 46 35 -36 50 12 -34 26 21 Uncertainty in time = +/- 2 secs [Prediction of 2008 Mar 20.0] Data for the target star ------------------------ * name: UCAC2 32475087 * constellation : Cetus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 00 31 32.5201 DE: +02 08 38.312 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .025, .024 ) * V mag [mag]: 11.9 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (18) Melpomene approx. diameter [km]: 141 approx. diameter ["]: .131 distance from Earth [AU]: 1.48200 * orbital information: orbit source: Preston date of fit: 2008 Mar 20 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 3744 number of rejected observations: 304 time covered by the observations: 1901 Aug 14 - 2008 Feb 17 1 sigma uncertainty ellipse (major, minor, PA): 0.016, 0.009, 78° remarks: * orbital elements for (18) Melpomene : Mean anomaly = 332.45519286 deg Arg. of pericenter = 227.76678047 deg Long. of node = 150.51393797 deg Inclination = 10.12875521 deg Eccentricity = 0.21842673 Semimajor axis = 2.29603637 AU Perihelion dist = 1.79452065 AU Mag: H = 6.51, G = 0.25 Epoch of elements : MJD 55018.22000000 TDT (2009 Jul 06.220) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Jul 6 18 Melpomene 5h 16.5m UT 11.9 0 31 32.520 2 8 38.31UCAC2 32475087 0.0 10.0 141 7.6 1.482 4.077 10.03 4.4328 2.140 102.07 22.67 5.2750 0.10667 -0.64374 10.29788 1.69099 -0.00447 -0.00190 2000 330.1265242009 628.00000227.766780150.513938 10.1287550.21842673 2.2960364 1.7945207 6.5 5.00.25 RATE 2.8329310 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.030 0.026 87 1.20 0.026 0 54545.5020090706_475087 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 20, 10:21 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org