IOTA/IOTA-ES occultation update for (191) Kolga / UCAC2 35549399 event on 2012 Oct 02, 19:26 UT Visible from Philippines, SE Asia Summary ------- On 2012 Oct 02 UT, the 101 km diameter asteroid (191) Kolga will occult a 11.0 mag star in the constellation Monoceros for observers along a path across Philippines, SE Asia. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.4 mag to 14.4 mag (the magnitude of the asteroid) for at most 5.5 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: 88 * date and approx. time of event: 2012 Oct 02, 19:21 - 2012 Oct 02, 19:26 UT * geocentric midpoint of event [JD]: 2456203.31036667 * magnitude of target star: 11.0 * magnitude drop [mag]: 3.4 * estimated maximum duration [s]: 5.5 * Moon: 93 % sunlit, 64° distance * Sun: 87° distance * rough path description: Philippines, SE Asia The occultation path -------------------- * approximate projected width [km]: 101 * 1 sigma uncertainty interval [path widths]: +/- 0.56 * 1 sigma uncertainty interval [seconds]: +/- 3.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .040 +/- .029) * 1 sigma uncertainty ellipse (major, minor, PA): ( .040", .029", 90° ) * approx speed of asteroid's shadow [km/s]: 18.3305 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC2 35549399 by 191 Kolga on 2012 Oct 2 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 69 0 0 14 4 12 19 21 9 1 79 -80 13 36 14 14 32 9 13 4 54 15 3 26 70 0 0 14 15 34 19 21 9 2 79 -79 13 47 38 14 43 29 13 16 19 15 14 44 71 0 0 14 26 36 19 21 9 3 79 -79 13 58 41 14 54 29 13 27 25 15 25 42 72 0 0 14 37 18 19 21 10 4 80 -78 14 9 25 15 5 10 13 38 11 15 36 21 73 0 0 14 47 40 19 21 10 5 80 -78 14 19 49 15 15 30 13 48 36 15 46 40 74 0 0 14 57 42 19 21 11 6 80 -77 14 29 52 15 25 31 13 58 42 15 56 39 75 0 0 15 7 24 19 21 11 7 80 -76 14 39 36 15 35 11 14 8 27 16 6 17 76 0 0 15 16 45 19 21 12 7 81 -76 14 48 59 15 44 31 14 17 51 16 15 35 77 0 0 15 25 46 19 21 13 8 81 -75 14 58 1 15 53 30 14 26 55 16 24 33 78 0 0 15 34 27 19 21 14 9 81 -74 15 6 43 16 2 9 14 35 39 16 33 11 79 0 0 15 42 46 19 21 15 10 81 -73 15 15 4 16 10 28 14 44 1 16 41 27 80 0 0 15 50 45 19 21 16 11 82 -73 15 23 4 16 18 25 14 52 3 16 49 24 81 0 0 15 58 23 19 21 17 12 82 -72 15 30 44 16 26 2 14 59 44 16 56 59 82 0 0 16 5 41 19 21 18 13 82 -71 15 38 2 16 33 18 15 7 4 17 4 14 83 0 0 16 12 37 19 21 20 14 82 -70 15 45 0 16 40 13 15 14 2 17 11 7 84 0 0 16 19 12 19 21 21 15 83 -69 15 51 36 16 46 47 15 20 40 17 17 40 85 0 0 16 25 26 19 21 23 16 83 -68 15 57 51 16 53 0 15 26 56 17 23 52 86 0 0 16 31 18 19 21 25 17 83 -67 16 3 44 16 58 52 15 32 51 17 29 42 87 0 0 16 36 50 19 21 26 18 84 -67 16 9 17 17 4 22 15 38 24 17 35 12 88 0 0 16 42 0 19 21 28 19 84 -66 16 14 28 17 9 31 15 43 36 17 40 20 89 0 0 16 46 48 19 21 30 20 84 -65 16 19 17 17 14 19 15 48 27 17 45 6 90 0 0 16 51 16 19 21 32 21 84 -64 16 23 45 17 18 45 15 52 55 17 49 32 91 0 0 16 55 21 19 21 34 22 85 -63 16 27 51 17 22 50 15 57 2 17 53 36 92 0 0 16 59 5 19 21 37 23 85 -62 16 31 36 17 26 33 16 0 48 17 57 19 93 0 0 17 2 28 19 21 39 24 85 -61 16 34 59 17 29 55 16 4 12 18 0 40 94 0 0 17 5 28 19 21 42 25 86 -60 16 38 0 17 32 55 16 7 13 18 3 39 95 0 0 17 8 7 19 21 44 26 86 -59 16 40 40 17 35 34 16 9 53 18 6 17 96 0 0 17 10 25 19 21 47 27 86 -59 16 42 57 17 37 51 16 12 11 18 8 34 97 0 0 17 12 20 19 21 49 28 86 -58 16 44 53 17 39 46 16 14 8 18 10 29 98 0 0 17 13 54 19 21 52 29 87 -57 16 46 27 17 41 19 16 15 42 18 12 2 99 0 0 17 15 5 19 21 55 30 87 -56 16 47 39 17 42 31 16 16 54 18 13 13 100 0 0 17 15 55 19 21 58 31 87 -55 16 48 29 17 43 21 16 17 44 18 14 2 101 0 0 17 16 23 19 22 1 32 88 -54 16 48 57 17 43 48 16 18 12 18 14 30 102 0 0 17 16 29 19 22 4 33 88 -53 16 49 3 17 43 54 16 18 18 18 14 36 103 0 0 17 16 13 19 22 7 34 88 -52 16 48 47 17 43 38 16 18 2 18 14 20 104 0 0 17 15 35 19 22 11 35 88 -51 16 48 9 17 43 1 16 17 24 18 13 43 105 0 0 17 14 35 19 22 14 36 89 -50 16 47 9 17 42 1 16 16 23 18 12 43 106 0 0 17 13 13 19 22 18 37 89 -49 16 45 46 17 40 39 16 15 1 18 11 22 107 0 0 17 11 29 19 22 21 38 89 -48 16 44 2 17 38 55 16 13 16 18 9 38 108 0 0 17 9 23 19 22 25 39 89 -47 16 41 56 17 36 50 16 11 9 18 7 33 109 0 0 17 6 55 19 22 29 39 90 -46 16 39 27 17 34 22 16 8 40 18 5 6 110 0 0 17 4 5 19 22 32 40 90 -46 16 36 36 17 31 32 16 5 49 18 2 17 111 0 0 17 0 52 19 22 36 41 90 -45 16 33 23 17 28 21 16 2 35 17 59 6 112 0 0 16 57 18 19 22 40 42 90 -44 16 29 48 17 24 47 15 58 59 17 55 33 113 0 0 16 53 21 19 22 44 43 91 -43 16 25 51 17 20 51 15 55 1 17 51 38 114 0 0 16 49 3 19 22 48 44 91 -42 16 21 32 17 16 33 15 50 41 17 47 21 115 0 0 16 44 22 19 22 53 45 91 -41 16 16 50 17 11 54 15 45 59 17 42 42 116 0 0 16 39 20 19 22 57 46 91 -40 16 11 47 17 6 52 15 40 54 17 37 41 117 0 0 16 33 55 19 23 1 47 92 -39 16 6 21 17 1 28 15 35 27 17 32 19 118 0 0 16 28 8 19 23 6 48 92 -38 16 0 33 16 55 42 15 29 38 17 26 34 119 0 0 16 21 59 19 23 10 49 92 -37 15 54 23 16 49 35 15 23 27 17 20 28 120 0 0 16 15 29 19 23 15 50 92 -36 15 47 51 16 43 5 15 16 54 17 14 0 121 0 0 16 8 36 19 23 19 51 92 -35 15 40 57 16 36 14 15 9 59 17 7 10 122 0 0 16 1 22 19 23 24 52 93 -34 15 33 42 16 29 1 15 2 41 16 59 58 123 0 0 15 53 45 19 23 29 53 93 -33 15 26 4 16 21 25 14 55 2 16 52 24 124 0 0 15 45 47 19 23 34 54 93 -32 15 18 4 16 13 29 14 47 1 16 44 29 125 0 0 15 37 27 19 23 39 55 93 -31 15 9 42 16 5 10 14 38 37 16 36 12 126 0 0 15 28 45 19 23 44 56 93 -30 15 0 59 15 56 30 14 29 52 16 27 33 127 0 0 15 19 41 19 23 49 57 93 -29 14 51 54 15 47 28 14 20 45 16 18 33 128 0 0 15 10 16 19 23 54 58 93 -28 14 42 27 15 38 4 14 11 17 16 9 11 129 0 0 15 0 29 19 23 59 59 94 -27 14 32 39 15 28 19 14 1 27 15 59 28 130 0 0 14 50 21 19 24 4 60 94 -26 14 22 29 15 18 12 13 51 15 15 49 23 131 0 0 14 39 52 19 24 10 61 94 -25 14 11 57 15 7 45 13 40 41 15 38 58 132 0 0 14 29 1 19 24 15 62 94 -24 14 1 5 14 56 55 13 29 47 15 28 10 133 0 0 14 17 48 19 24 20 63 94 -23 13 49 51 14 45 45 13 18 30 15 17 2 134 0 0 14 6 15 19 24 26 64 94 -22 13 38 16 14 34 14 13 6 53 15 5 33 135 0 0 13 54 21 19 24 31 65 94 -21 13 26 19 14 22 21 12 54 55 14 53 43 136 0 0 13 42 6 19 24 37 66 94 -20 13 14 2 14 10 8 12 42 36 14 41 32 137 0 0 13 29 30 19 24 43 67 94 -19 13 1 24 13 57 34 12 29 55 14 29 0 138 0 0 13 16 33 19 24 48 68 93 -18 12 48 26 13 44 40 12 16 54 14 16 8 139 0 0 13 3 16 19 24 54 69 93 -17 12 35 7 13 31 25 12 3 33 14 2 55 140 0 0 12 49 39 19 25 0 70 93 -16 12 21 27 13 17 49 11 49 51 13 49 22 141 0 0 12 35 41 19 25 6 71 93 -15 12 7 27 13 3 54 11 35 49 13 35 29 142 0 0 12 21 23 19 25 12 72 92 -14 11 53 8 12 49 38 11 21 27 13 21 16 143 0 0 12 6 46 19 25 18 73 92 -13 11 38 28 12 35 3 11 6 45 13 6 43 144 0 0 11 51 49 19 25 24 74 91 -12 11 23 29 12 20 8 10 51 43 12 51 50 145 0 0 11 36 32 19 25 30 75 91 -11 11 8 10 12 4 53 10 36 22 12 36 38 146 0 0 11 20 56 19 25 36 76 90 -10 10 52 32 11 49 20 10 20 41 12 21 7 147 0 0 11 5 1 19 25 42 77 89 -9 10 36 35 11 33 27 10 4 42 12 5 16 148 0 0 10 48 48 19 25 49 78 88 -8 10 20 19 11 17 16 9 48 23 11 49 7 149 0 0 10 32 15 19 25 55 79 86 -7 10 3 44 11 0 46 9 31 47 11 32 40 150 0 0 10 15 25 19 26 1 80 84 -6 9 46 52 10 43 57 9 14 51 11 15 54 151 0 0 9 58 16 19 26 7 81 82 -5 9 29 41 10 26 51 8 57 38 10 58 50 152 0 0 9 40 50 19 26 14 82 79 -4 9 12 12 10 9 27 8 40 7 10 41 28 153 0 0 9 23 6 19 26 20 83 76 -3 8 54 26 9 51 45 8 22 19 10 23 49 154 0 0 9 5 5 19 26 26 84 71 -2 8 36 23 9 33 46 8 4 13 10 5 53 155 0 0 8 46 47 19 26 33 85 64 -1 8 18 3 9 15 30 7 45 51 9 47 39 156 0 0 8 28 13 19 26 39 85 55 0 7 59 27 8 56 58 7 27 12 9 29 10 Uncertainty in time = +/- 4 secs Prediction of 2012 Jul 10.0 Data for the target star ------------------------ * name: UCAC2 35549399 * constellation : Monoceros * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 06 52 39.1104 DE: +10 59 45.502 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .036, .027 ) * V mag [mag]: 11.0 * B mag [mag]: 0.0 * Apparent position with proper motion RA(deg): 103.3434755783 DE(deg): 10.9793748906 * Equation of equinoxes (radians) : 0.000062456448752 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (191) Kolga approx. diameter [km]: 101 approx. diameter ["]: .054 distance from Earth [AU]: 2.59300 * orbital information: orbit source: Preston date of fit: 2012 Jul 09 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1164 number of rejected observations: 95 time covered by the observations: 1902 Jul 09 - 2012 Jan 04 1 sigma uncertainty ellipse (major, minor, PA): 0.017, 0.010, 88° remarks: * orbital elements for (191) Kolga : Mean anomaly = 45.46763604 deg Arg. of pericenter = 228.08825864 deg Long. of node = 159.36269914 deg Inclination = 11.50094336 deg Eccentricity = 0.09156768 Semimajor axis = 2.89679742 AU Perihelion dist = 2.63154440 AU Mag: H = 8.90, G = 0.15 Epoch of elements : MJD 56202.81000000 TDT (2012 Oct 02.810) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Oct 2 191 Kolga 19h 26.9m UT 11.0 6 52 39.110 10 59 45.50UCAC2 35549399 0.0 14.4 101 5.5 2.593 2.270 -10.66 159.5158 10.999 -114.45 -3.96 19.4488 -0.01998 -0.05868 9.85743 -3.14258 -0.00566 0.00045 2000 44.9058992012 930.00000228.088259159.362699 11.5009430.09156768 2.8967974 2.6315444 9.1 5.00.15 RATE 1.9990650 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.040 0.029 90 1.56 0.030 0 0 4 2 056118.0020121002_549399 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Aug 06, 17:09 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org