IOTA/IOTA-ES occultation update for (488) Kreusa / TYC 1927-01777-1 event on 2012 Oct 29, 20:47 UT Visible from SE Asia Summary ------- On 2012 Oct 29 UT, the 173 km diameter asteroid (488) Kreusa will occult a 11.1 mag star in the constellation Cancer for observers along a path across SE Asia. In the case of an occultation, the combined light of the asteroid and the star will drop by 2.1 mag to 13.1 mag (the magnitude of the asteroid) for at most 11.7 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: 99 * date and approx. time of event: 2012 Oct 29, 20:40 - 2012 Oct 29, 20:48 UT * geocentric midpoint of event [JD]: 2456230.36660417 * magnitude of target star: 11.1 * magnitude drop [mag]: 2.1 * estimated maximum duration [s]: 11.7 * Moon: 100 % sunlit, 82° distance * Sun: 97° distance * rough path description: SE Asia Additional comments ------------------- 9" double star The occultation path -------------------- * approximate projected width [km]: 174 * 1 sigma uncertainty interval [path widths]: +/- 0.30 * 1 sigma uncertainty interval [seconds]: +/- 3.8 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .033 +/- .029) * 1 sigma uncertainty ellipse (major, minor, PA): ( .033", .029", 91° ) * approx speed of asteroid's shadow [km/s]: 14.6911 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1927-01777-1 by 488 Kreusa on 2012 Oct 29 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 50 0 0 -12 56 40 20 40 45 0 66 -63 .. .. .. -12 5 0 .. .. .. -11 34 3 51 0 0 -12 30 13 20 40 45 1 66 -63 -13 22 1 -11 38 31 -13 53 8 -11 7 31 52 0 0 -12 3 35 20 40 46 2 65 -63 -12 55 26 -11 11 51 -13 26 35 -10 40 50 53 0 0 -11 36 48 20 40 46 3 65 -64 -12 28 41 -10 45 1 -12 59 51 -10 13 59 54 0 0 -11 9 52 20 40 47 4 65 -64 -12 1 47 -10 18 3 -12 32 58 - 9 47 0 55 0 0 -10 42 48 20 40 47 5 65 -64 -11 34 44 - 9 50 57 -12 5 57 - 9 19 52 56 0 0 -10 15 35 20 40 48 7 65 -64 -11 7 34 - 9 23 43 -11 38 47 - 8 52 37 57 0 0 - 9 48 16 20 40 49 8 64 -64 -10 40 16 - 8 56 22 -11 11 30 - 8 25 15 58 0 0 - 9 20 50 20 40 50 9 64 -64 -10 12 51 - 8 28 55 -10 44 7 - 7 57 48 59 0 0 - 8 53 19 20 40 52 10 64 -64 - 9 45 21 - 8 1 22 -10 16 37 - 7 30 14 60 0 0 - 8 25 42 20 40 53 11 64 -64 - 9 17 46 - 7 33 45 - 9 49 2 - 7 2 37 61 0 0 - 7 58 2 20 40 55 12 64 -63 - 8 50 6 - 7 6 3 - 9 21 23 - 6 34 55 62 0 0 - 7 30 18 20 40 57 13 64 -63 - 8 22 22 - 6 38 19 - 8 53 39 - 6 7 10 63 0 0 - 7 2 30 20 40 59 14 64 -63 - 7 54 35 - 6 10 31 - 8 25 53 - 5 39 22 64 0 0 - 6 34 41 20 41 1 15 63 -63 - 7 26 46 - 5 42 42 - 7 58 4 - 5 11 33 65 0 0 - 6 6 51 20 41 3 16 63 -62 - 6 58 55 - 5 14 52 - 7 30 13 - 4 43 42 66 0 0 - 5 39 0 20 41 6 18 63 -62 - 6 31 4 - 4 47 1 - 7 2 21 - 4 15 52 67 0 0 - 5 11 8 20 41 8 19 63 -62 - 6 3 12 - 4 19 10 - 6 34 29 - 3 48 2 68 0 0 - 4 43 18 20 41 11 20 63 -61 - 5 35 21 - 3 51 21 - 6 6 38 - 3 20 13 69 0 0 - 4 15 30 20 41 14 21 63 -61 - 5 7 32 - 3 23 33 - 5 38 48 - 2 52 26 70 0 0 - 3 47 44 20 41 17 22 63 -60 - 4 39 44 - 2 55 48 - 5 11 0 - 2 24 41 71 0 0 - 3 20 1 20 41 20 23 63 -60 - 4 12 0 - 2 28 7 - 4 43 15 - 1 57 0 72 0 0 - 2 52 21 20 41 24 24 63 -59 - 3 44 19 - 2 0 29 - 4 15 33 - 1 29 24 73 0 0 - 2 24 47 20 41 27 25 63 -58 - 3 16 43 - 1 32 56 - 3 47 56 - 1 1 52 74 0 0 - 1 57 18 20 41 31 26 62 -58 - 2 49 12 - 1 5 29 - 3 20 24 - 0 34 26 75 0 0 - 1 29 55 20 41 35 27 62 -57 - 2 21 47 - 0 38 9 - 2 52 57 - 0 7 7 76 0 0 - 1 2 39 20 41 39 29 62 -56 - 1 54 29 - 0 10 55 - 2 25 37 0 20 5 77 0 0 - 0 35 31 20 41 43 30 62 -56 - 1 27 18 0 16 11 - 1 58 25 0 47 10 78 0 0 - 0 8 30 20 41 47 31 62 -55 - 1 0 15 0 43 8 - 1 31 20 1 14 5 79 0 0 0 18 21 20 41 51 32 62 -54 - 0 33 21 1 9 56 - 1 4 25 1 40 52 80 0 0 0 45 2 20 41 56 33 62 -53 - 0 6 36 1 36 35 - 0 37 38 2 7 28 81 0 0 1 11 33 20 42 1 34 62 -53 0 19 58 2 3 2 - 0 11 2 2 33 53 82 0 0 1 37 52 20 42 6 35 62 -52 0 46 21 2 29 18 0 15 23 3 0 8 83 0 0 2 4 0 20 42 10 36 62 -51 1 12 32 2 55 23 0 41 37 3 26 10 84 0 0 2 29 56 20 42 16 37 62 -50 1 38 31 3 21 14 1 7 38 3 51 59 85 0 0 2 55 38 20 42 21 39 62 -49 2 4 18 3 46 53 1 33 27 4 17 35 86 0 0 3 21 6 20 42 26 40 62 -49 2 29 50 4 12 17 1 59 2 4 42 57 87 0 0 3 46 20 20 42 31 41 62 -48 2 55 9 4 37 27 2 24 22 5 8 4 88 0 0 4 11 20 20 42 37 42 62 -47 3 20 12 5 2 22 2 49 28 5 32 57 89 0 0 4 36 3 20 42 43 43 62 -46 3 45 0 5 27 1 3 14 19 5 57 33 90 0 0 5 0 31 20 42 48 44 62 -45 4 9 32 5 51 24 3 38 54 6 21 53 91 0 0 5 24 41 20 42 54 45 62 -44 4 33 47 6 15 30 4 3 12 6 45 57 92 0 0 5 48 35 20 43 0 46 62 -43 4 57 46 6 39 18 4 27 13 7 9 42 93 0 0 6 12 11 20 43 6 47 62 -42 5 21 26 7 2 49 4 50 57 7 33 10 94 0 0 6 35 28 20 43 13 48 62 -41 5 44 49 7 26 2 5 14 22 7 56 20 95 0 0 6 58 27 20 43 19 49 62 -41 6 7 52 7 48 56 5 37 29 8 19 11 96 0 0 7 21 6 20 43 25 51 62 -40 6 30 37 8 11 30 6 0 16 8 41 42 97 0 0 7 43 26 20 43 32 52 62 -39 6 53 2 8 33 45 6 22 44 9 3 53 98 0 0 8 5 26 20 43 38 53 61 -38 7 15 7 8 55 39 6 44 52 9 25 45 99 0 0 8 27 5 20 43 45 54 61 -37 7 36 51 9 17 13 7 6 40 9 47 16 100 0 0 8 48 23 20 43 51 55 61 -36 7 58 15 9 38 26 7 28 7 10 8 25 101 0 0 9 9 20 20 43 58 56 61 -35 8 19 17 9 59 18 7 49 12 10 29 14 102 0 0 9 29 55 20 44 5 57 61 -34 8 39 57 10 19 47 8 9 56 10 49 41 103 0 0 9 50 8 20 44 12 58 61 -33 9 0 16 10 39 55 8 30 17 11 9 45 104 0 0 10 9 59 20 44 19 59 61 -32 9 20 12 10 59 41 8 50 17 11 29 27 105 0 0 10 29 27 20 44 26 60 61 -31 9 39 45 11 19 4 9 9 54 11 48 47 106 0 0 10 48 32 20 44 33 61 60 -30 9 58 56 11 38 3 9 29 7 12 7 44 107 0 0 11 7 14 20 44 40 62 60 -29 10 17 43 11 56 40 9 47 58 12 26 17 108 0 0 11 25 32 20 44 47 63 60 -28 10 36 7 12 14 53 10 6 24 12 44 27 109 0 0 11 43 27 20 44 54 64 60 -27 10 54 7 12 32 42 10 24 27 13 2 13 110 0 0 12 0 58 20 45 1 65 59 -26 11 11 42 12 50 8 10 42 6 13 19 35 111 0 0 12 18 4 20 45 9 66 59 -26 11 28 54 13 7 9 10 59 21 13 36 33 112 0 0 12 34 46 20 45 16 67 58 -25 11 45 41 13 23 45 11 16 11 13 53 7 113 0 0 12 51 3 20 45 23 68 58 -24 12 2 3 13 39 57 11 32 36 14 9 16 114 0 0 13 6 55 20 45 31 69 57 -23 12 18 0 13 55 45 11 48 36 14 25 0 115 0 0 13 22 22 20 45 38 70 57 -22 12 33 32 14 11 7 12 4 12 14 40 20 116 0 0 13 37 24 20 45 46 71 56 -21 12 48 39 14 26 4 12 19 21 14 55 14 117 0 0 13 52 1 20 45 53 72 55 -20 13 3 21 14 40 36 12 34 6 15 9 43 118 0 0 14 6 12 20 46 0 73 54 -19 13 17 37 14 54 43 12 48 25 15 23 47 119 0 0 14 19 58 20 46 8 74 53 -18 13 31 27 15 8 24 13 2 18 15 37 25 120 0 0 14 33 18 20 46 16 75 51 -17 13 44 51 15 21 39 13 15 45 15 50 38 121 0 0 14 46 12 20 46 23 76 50 -16 13 57 50 15 34 29 13 28 46 16 3 25 122 0 0 14 58 40 20 46 31 77 48 -15 14 10 22 15 46 53 13 41 21 16 15 46 123 0 0 15 10 42 20 46 38 77 46 -14 14 22 28 15 58 51 13 53 29 16 27 42 124 0 0 15 22 18 20 46 46 78 44 -13 14 34 8 16 10 22 14 5 12 16 39 11 125 0 0 15 33 28 20 46 53 79 41 -12 14 45 22 16 21 28 14 16 28 16 50 15 126 0 0 15 44 11 20 47 1 80 38 -11 14 56 9 16 32 8 14 27 18 17 0 52 127 0 0 15 54 28 20 47 8 81 34 -10 15 6 30 16 42 22 14 37 41 17 11 3 128 0 0 16 4 19 20 47 16 81 29 -9 15 16 24 16 52 9 14 47 37 17 20 48 129 0 0 16 13 43 20 47 24 82 24 -9 15 25 52 17 1 30 14 57 7 17 30 7 130 0 0 16 22 41 20 47 31 82 18 -8 15 34 53 17 10 24 15 6 10 17 39 0 131 0 0 16 31 13 20 47 39 83 11 -7 15 43 28 17 18 53 15 14 46 17 47 26 132 0 0 16 39 17 20 47 46 83 4 -6 15 51 36 17 26 54 15 22 56 17 55 26 133 0 0 16 46 56 20 47 54 83 356 -5 15 59 17 17 34 30 15 30 39 18 3 0 134 0 0 16 54 7 20 48 1 83 348 -4 16 6 31 17 41 39 15 37 54 18 10 7 135 0 0 17 0 52 20 48 9 83 340 -3 16 13 18 17 48 21 15 44 43 18 16 48 136 0 0 17 7 10 20 48 16 83 333 -2 16 19 39 17 54 37 15 51 6 18 23 3 137 0 0 17 13 2 20 48 24 82 326 -1 16 25 33 18 0 26 15 57 1 18 28 51 138 0 0 17 18 27 20 48 31 82 320 0 16 31 0 18 5 49 16 2 29 18 34 13 Uncertainty in time = +/- 4 secs Prediction of 2012 Oct 26.0 Data for the target star ------------------------ * name: TYC 1927-01777-1 * constellation : Cancer * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 08 11 11.5661 DE: +23 31 05.442 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .026, .027 ) * V mag [mag]: 11.1 * B mag [mag]: 13.2 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (488) Kreusa approx. diameter [km]: 173 approx. diameter ["]: .094 distance from Earth [AU]: 2.53700 * orbital information: orbit source: Preston date of fit: 2012 Oct 25 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 903 number of rejected observations: 105 time covered by the observations: 1901 Feb 15 - 2012 Sep 25 1 sigma uncertainty ellipse (major, minor, PA): 0.020, 0.009, 92° remarks: * orbital elements for (488) Kreusa : Mean anomaly = 318.63484876 deg Arg. of pericenter = 70.89186804 deg Long. of node = 84.24762081 deg Inclination = 11.52137818 deg Eccentricity = 0.15950774 Semimajor axis = 3.16860128 AU Perihelion dist = 2.66318485 AU Mag: H = 7.89, G = 0.15 Epoch of elements : MJD 56229.86700000 TDT (2012 Oct 29.867) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Oct 29 488 Kreusa 20h 47.9m UT 11.1 8 11 11.566 23 31 5.44TYC 1927-01777-1 13.2 13.1 173 11.7 2.537 2.072 3.64 132.2378 23.517 -136.05 -13.80 20.7985 0.01116 -0.11815 8.22548 1.04870 -0.00565 0.00121 2000 316.91064820121020.00000 70.891868 84.247621 11.5213780.15950774 3.1686013 2.6631849 7.8 5.00.15 RATE 1.7474420 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.033 0.029 91 1.30 0.029 0 0 1 2 056226.0020121029_1777-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Oct 25, 21:27 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org