IOTA/IOTA-ES occultation update for (818) Kapteynia / TYC 6915-00796-1 event on 2009 Apr 09, 19:41 UT Visible from Summary ------- On 2009 Apr 09 UT, the 50 km diameter asteroid (818) Kapteynia will occult a 10.4 mag star in the constellation Microscopium for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 4.6 mag to 15.0 mag (the magnitude of the asteroid) for at most 2.0 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: 54 * date and approx. time of event: 2009 Apr 09, 19:37 - 2009 Apr 09, 19:40 UT * magnitude of target star: 10.4 * magnitude drop [mag]: 4.6 * estimated maximum duration [s]: 2.0 * Moon: 100 % sunlit, 99° distance * Sun: 77° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 50 * 1 sigma uncertainty interval [path widths]: +/- 1.18 * 1 sigma uncertainty interval [seconds]: +/- 3.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .037 +/- .026) * 1 sigma uncertainty ellipse (major, minor, PA): ( .037", .026", 88° ) * approx speed of asteroid's shadow [km/s]: 24.6926 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6915-00796-1 by 818 Kapteynia on 2009 Apr 9 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 89 0 0 6 31 0 19 37 38 1 118 -63 6 15 36 6 46 25 5 39 16 7 22 48 90 0 0 5 59 1 19 37 38 2 118 -62 5 43 36 6 14 25 5 7 16 6 50 49 91 0 0 5 26 57 19 37 39 3 118 -62 5 11 32 5 42 22 4 35 11 6 18 46 92 0 0 4 54 50 19 37 39 4 118 -61 4 39 26 5 10 15 4 3 5 5 46 40 93 0 0 4 22 42 19 37 39 5 118 -60 4 7 17 4 38 7 3 30 56 5 14 31 94 0 0 3 50 32 19 37 40 6 119 -60 3 35 7 4 5 57 2 58 46 4 42 21 95 0 0 3 18 22 19 37 40 7 119 -59 3 2 57 3 33 47 2 26 36 4 10 11 96 0 0 2 46 12 19 37 41 9 119 -58 2 30 48 3 1 37 1 54 28 3 38 0 97 0 0 2 14 4 19 37 42 10 119 -57 1 58 40 2 29 29 1 22 21 3 5 52 98 0 0 1 41 59 19 37 43 11 119 -57 1 26 35 1 57 23 0 50 17 2 33 45 99 0 0 1 9 57 19 37 44 12 119 -56 0 54 34 1 25 21 0 18 16 2 1 42 100 0 0 0 38 0 19 37 45 13 119 -55 0 22 37 0 53 23 - 0 13 39 1 29 42 101 0 0 0 6 7 19 37 46 14 119 -54 - 0 9 15 0 21 30 - 0 45 29 0 57 48 102 0 0 - 0 25 38 19 37 47 15 119 -53 - 0 41 0 - 0 10 17 - 1 17 13 0 26 0 103 0 0 - 0 57 17 19 37 49 16 119 -52 - 1 12 38 - 0 41 56 - 1 48 49 - 0 5 42 104 0 0 - 1 28 48 19 37 50 18 119 -52 - 1 44 8 - 1 13 28 - 2 20 17 - 0 37 15 105 0 0 - 2 0 10 19 37 52 19 119 -51 - 2 15 29 - 1 44 51 - 2 51 36 - 1 8 40 106 0 0 - 2 31 22 19 37 54 20 119 -50 - 2 46 39 - 2 16 4 - 3 22 44 - 1 39 55 107 0 0 - 3 2 23 19 37 55 21 119 -49 - 3 17 40 - 2 47 6 - 3 53 42 - 2 11 0 108 0 0 - 3 33 13 19 37 57 22 119 -48 - 3 48 28 - 3 17 57 - 4 24 28 - 2 41 54 109 0 0 - 4 3 50 19 37 59 23 119 -47 - 4 19 5 - 3 48 35 - 4 55 1 - 3 12 35 110 0 0 - 4 34 14 19 38 1 24 119 -46 - 4 49 28 - 4 19 1 - 5 25 21 - 3 43 4 111 0 0 - 5 4 25 19 38 3 25 118 -45 - 5 19 36 - 4 49 13 - 5 55 27 - 4 13 18 112 0 0 - 5 34 20 19 38 6 27 118 -44 - 5 49 31 - 5 19 9 - 6 25 18 - 4 43 19 113 0 0 - 6 4 0 19 38 8 28 118 -43 - 6 19 9 - 5 48 51 - 6 54 53 - 5 13 4 114 0 0 - 6 33 24 19 38 10 29 118 -42 - 6 48 32 - 6 18 16 - 7 24 12 - 5 42 32 115 0 0 - 7 2 31 19 38 13 30 118 -41 - 7 17 37 - 6 47 25 - 7 53 14 - 6 11 44 116 0 0 - 7 31 20 19 38 15 31 118 -40 - 7 46 25 - 7 16 16 - 8 21 58 - 6 40 39 117 0 0 - 7 59 51 19 38 18 32 118 -39 - 8 14 54 - 7 44 48 - 8 50 23 - 7 9 16 118 0 0 - 8 28 3 19 38 21 33 118 -38 - 8 43 4 - 8 13 2 - 9 18 29 - 7 37 33 119 0 0 - 8 55 56 19 38 24 34 118 -37 - 9 10 55 - 8 40 56 - 9 46 16 - 8 5 31 120 0 0 - 9 23 28 19 38 26 35 118 -36 - 9 38 25 - 9 8 30 -10 13 42 - 8 33 10 121 0 0 - 9 50 39 19 38 29 37 117 -35 -10 5 35 - 9 35 43 -10 40 48 - 9 0 27 122 0 0 -10 17 29 19 38 32 38 117 -34 -10 32 23 -10 2 35 -11 7 32 - 9 27 24 123 0 0 -10 43 58 19 38 35 39 117 -33 -10 58 50 -10 29 5 -11 33 54 - 9 53 58 124 0 0 -11 10 4 19 38 38 40 117 -32 -11 24 54 -10 55 13 -11 59 54 -10 20 11 125 0 0 -11 35 47 19 38 42 41 117 -32 -11 50 35 -11 20 59 -12 25 31 -10 46 0 126 0 0 -12 1 7 19 38 45 42 117 -31 -12 15 53 -11 46 21 -12 50 44 -11 11 27 127 0 0 -12 26 3 19 38 48 43 117 -30 -12 40 48 -12 11 19 -13 15 34 -11 36 30 128 0 0 -12 50 36 19 38 51 44 117 -29 -13 5 18 -12 35 53 -13 39 59 -12 1 8 129 0 0 -13 14 43 19 38 55 45 116 -28 -13 29 24 -13 0 3 -14 4 0 -12 25 23 130 0 0 -13 38 26 19 38 58 46 116 -27 -13 53 5 -13 23 47 -14 27 37 -12 49 12 131 0 0 -14 1 44 19 39 2 47 116 -26 -14 16 20 -13 47 7 -14 50 48 -13 12 37 132 0 0 -14 24 36 19 39 5 48 116 -25 -14 39 11 -14 10 1 -15 13 33 -13 35 36 133 0 0 -14 47 2 19 39 9 49 116 -24 -15 1 35 -14 32 30 -15 35 53 -13 58 9 134 0 0 -15 9 3 19 39 12 50 116 -23 -15 23 33 -14 54 32 -15 57 47 -14 20 16 135 0 0 -15 30 37 19 39 16 51 115 -22 -15 45 5 -15 16 8 -16 19 14 -14 41 56 136 0 0 -15 51 44 19 39 20 52 115 -21 -16 6 11 -15 37 17 -16 40 15 -15 3 10 137 0 0 -16 12 25 19 39 24 54 115 -20 -16 26 49 -15 58 0 -17 0 48 -15 23 57 138 0 0 -16 32 38 19 39 27 55 115 -19 -16 47 1 -16 18 15 -17 20 55 -15 44 17 139 0 0 -16 52 25 19 39 31 56 115 -18 -17 6 45 -16 38 4 -17 40 35 -16 4 10 140 0 0 -17 11 43 19 39 35 57 115 -17 -17 26 2 -16 57 24 -17 59 48 -16 23 36 141 0 0 -17 30 35 19 39 39 58 115 -16 -17 44 52 -17 16 18 -18 18 33 -16 42 34 142 0 0 -17 48 59 19 39 43 59 115 -15 -18 3 14 -17 34 43 -18 36 50 -17 1 4 143 0 0 -18 6 55 19 39 47 60 115 -14 -18 21 8 -17 52 41 -18 54 40 -17 19 6 144 0 0 -18 24 23 19 39 51 61 114 -13 -18 38 34 -18 10 11 -19 12 2 -17 36 40 145 0 0 -18 41 23 19 39 55 62 114 -12 -18 55 32 -18 27 13 -19 28 56 -17 53 46 146 0 0 -18 57 55 19 39 59 63 114 -11 -19 12 3 -18 43 47 -19 45 22 -18 10 24 147 0 0 -19 13 59 19 40 3 64 114 -10 -19 28 5 -18 59 52 -20 1 20 -18 26 34 148 0 0 -19 29 34 19 40 7 65 114 -9 -19 43 38 -19 15 29 -20 16 50 -18 42 15 149 0 0 -19 44 41 19 40 11 65 114 -9 -19 58 44 -19 30 38 -20 31 51 -18 57 28 150 0 0 -19 59 20 19 40 15 66 114 -8 -20 13 21 -19 45 19 -20 46 25 -19 12 12 151 0 0 -20 13 31 19 40 19 67 114 -7 -20 27 30 -19 59 31 -21 0 30 -19 26 28 152 0 0 -20 27 13 19 40 23 68 115 -6 -20 41 11 -20 13 15 -21 14 7 -19 40 15 153 0 0 -20 40 26 19 40 27 69 115 -5 -20 54 23 -20 26 30 -21 27 15 -19 53 34 154 0 0 -20 53 11 19 40 31 70 115 -4 -21 7 6 -20 39 16 -21 39 55 -20 6 24 155 0 0 -21 5 28 19 40 35 71 115 -3 -21 19 21 -20 51 34 -21 52 7 -20 18 45 156 0 0 -21 17 16 19 40 40 72 116 -2 -21 31 8 -21 3 24 -22 3 51 -20 30 38 157 0 0 -21 28 36 19 40 44 73 116 -1 -21 42 26 -21 14 45 -22 15 6 -20 42 2 158 0 0 -21 39 27 19 40 48 74 116 0 -21 53 16 -21 25 37 -22 25 53 -20 52 58 Uncertainty in time = +/- 3 secs [Prediction of 2008 Apr 25.0] Data for the target star ------------------------ * name: TYC 6915-00796-1 * constellation : Microscopium * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 20 29 18.0280 DE: -27 50 01.813 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .029, .023 ) * V mag [mag]: 10.4 * B mag [mag]: 10.9 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (818) Kapteynia approx. diameter [km]: 50 approx. diameter ["]: .022 distance from Earth [AU]: 3.15100 * orbital information: orbit source: Preston date of fit: 2008 Apr 24 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 732 number of rejected observations: 45 time covered by the observations: 1916 Feb 21 - 2008 Apr 19 1 sigma uncertainty ellipse (major, minor, PA): 0.023, 0.012, 86° remarks: * orbital elements for (818) Kapteynia : Mean anomaly = 290.62536929 deg Arg. of pericenter = 294.43345706 deg Long. of node = 71.01989975 deg Inclination = 15.66879892 deg Eccentricity = 0.09782517 Semimajor axis = 3.16986504 AU Perihelion dist = 2.85977245 AU Mag: H = 9.18, G = 0.15 Epoch of elements : MJD 54930.82100000 TDT (2009 Apr 09.821) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Apr 9 818 Kapteynia 19h 41.9m UT 10.4 20 29 18.028-27 50 1.81TYC 6915-00796-1 10.9 15.0 50 2.0 3.151 2.928 -2.16 173.6594 -27.833 -115.12 7.85 19.6989 0.00539 0.07769 13.91572 -0.77292 -0.00540 -0.00155 2000 290.4819902009 4 9.00000294.433457 71.019900 15.6687990.09782517 3.1698650 2.8597725 9.1 5.00.15 RATE 1.7463970 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.037 0.026 88 2.18 0.026 0 54581.5020090409_0796-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 25, 06:20 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org