IOTA/IOTA-ES occultation update for (2907) Nekrasov / HIP 18477 event on 2012 Sep 21, 16:40 UT Visible from Japan, E Russia Summary ------- On 2012 Sep 21 UT, the 17 km diameter asteroid (2907) Nekrasov will occult a 9.4 mag star in the constellation Taurus for observers along a path across Japan, E Russia. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.9 mag to 16.3 mag (the magnitude of the asteroid) for at most 2.8 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: 10 * date and approx. time of event: 2012 Sep 21, 16:22 - 2012 Sep 21, 16:52 UT * geocentric midpoint of event [JD]: 2456192.19454583 * magnitude of target star: 9.4 * magnitude drop [mag]: 6.9 * estimated maximum duration [s]: 2.8 * Moon: 37 % sunlit, 164° distance * Sun: 119° distance * rough path description: Japan, E Russia The occultation path -------------------- * approximate projected width [km]: 17 * 1 sigma uncertainty interval [path widths]: +/- 6.58 * 1 sigma uncertainty interval [seconds]: +/- 14.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .077 +/- .049) * 1 sigma uncertainty ellipse (major, minor, PA): ( .078", .048", 83° ) * approx speed of asteroid's shadow [km/s]: 6.0177 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of HIP 18477 by 2907 Nekrasov on 2012 Sep 21 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 ' " Longitude Longitude Longitude Longitude Latitude Latitude Latitude Latitude -165 0 0 -25 55 16 16 52 54 44 317 0 -26 2 48 -25 47 42 -27 41 51 -24 8 0 -166 0 0 -24 43 58 16 52 35 45 318 -1 -24 51 38 -24 36 19 -26 32 7 -22 55 8 -167 0 0 -23 30 20 16 52 14 47 318 -2 -23 38 6 -23 22 33 -25 20 4 -21 39 52 -168 0 0 -22 14 18 16 51 52 48 319 -3 -22 22 11 -22 6 24 -24 5 37 -20 22 13 -169 0 0 -20 55 51 16 51 28 50 319 -4 -21 3 51 -20 47 51 -22 48 47 -19 2 9 -170 0 0 -19 35 1 16 51 4 52 319 -5 -19 43 8 -19 26 54 -21 29 33 -17 39 41 -171 0 0 -18 11 47 16 50 39 53 319 -6 -18 20 0 -18 3 33 -20 7 55 -16 14 50 -172 0 0 -16 46 10 16 50 12 55 319 -7 -16 54 31 -16 37 50 -18 43 53 -14 47 38 -173 0 0 -15 18 14 16 49 44 57 320 -9 -15 26 41 -15 9 47 -17 17 30 -13 18 8 -174 0 0 -13 48 2 16 49 15 59 320 -10 -13 56 35 -13 39 28 -15 48 48 -11 46 25 -175 0 0 -12 15 39 16 48 45 61 320 -11 -12 24 18 -12 6 59 -14 17 53 -10 12 34 -176 0 0 -10 41 11 16 48 14 63 320 -12 -10 49 56 -10 32 25 -12 44 49 - 8 36 44 -177 0 0 - 9 4 46 16 47 42 65 319 -13 - 9 13 37 - 8 55 55 -11 9 43 - 6 59 1 -178 0 0 - 7 26 34 16 47 8 67 319 -14 - 7 35 30 - 7 17 38 - 9 32 43 - 5 19 37 -179 0 0 - 5 46 45 16 46 34 69 319 -16 - 5 55 46 - 5 37 44 - 7 54 1 - 3 38 43 -180 0 0 - 4 5 31 16 45 59 71 318 -17 - 4 14 36 - 3 56 26 - 6 13 46 - 1 56 33 179 0 0 - 2 23 7 16 45 23 73 317 -18 - 2 32 15 - 2 13 58 - 4 32 11 - 0 13 20 178 0 0 - 0 39 46 16 44 46 75 316 -19 - 0 48 57 - 0 30 34 - 2 49 31 1 30 39 177 0 0 1 4 16 16 44 9 77 315 -20 0 55 3 1 13 29 - 1 6 1 3 15 9 176 0 0 2 48 42 16 43 31 79 312 -21 2 39 27 2 57 56 0 38 3 4 59 52 175 0 0 4 33 14 16 42 53 81 309 -22 4 23 59 4 42 30 2 22 25 6 44 31 174 0 0 6 17 36 16 42 15 83 305 -23 6 8 21 6 26 51 4 6 48 8 28 49 173 0 0 8 1 30 16 41 37 85 296 -24 7 52 16 8 10 45 5 50 53 10 12 28 172 0 0 9 44 40 16 40 59 86 281 -26 9 35 28 9 53 52 7 34 25 11 55 12 171 0 0 11 26 49 16 40 21 87 249 -26 11 17 39 11 35 59 9 17 6 13 36 45 170 0 0 13 7 42 16 39 44 87 208 -27 12 58 35 13 16 49 10 58 41 15 16 52 169 0 0 14 47 4 16 39 7 85 184 -28 14 38 1 14 56 8 12 38 55 16 55 20 168 0 0 16 24 45 16 38 31 84 172 -29 16 15 46 16 33 43 14 17 35 18 31 58 167 0 0 18 0 31 16 37 56 82 166 -30 17 51 37 18 9 25 15 54 28 20 6 34 166 0 0 19 34 13 16 37 21 80 161 -31 19 25 25 19 43 2 17 29 24 21 39 0 165 0 0 21 5 44 16 36 47 79 158 -31 20 57 1 21 14 27 19 2 15 23 9 9 164 0 0 22 34 56 16 36 14 77 156 -32 22 26 19 22 43 33 20 32 52 24 36 55 163 0 0 24 1 45 16 35 42 75 154 -33 23 53 15 24 10 16 22 1 10 26 2 14 162 0 0 25 26 7 16 35 11 73 153 -33 25 17 43 25 34 31 23 27 3 27 25 2 161 0 0 26 47 59 16 34 42 72 151 -34 26 39 41 26 56 16 24 50 29 28 45 19 160 0 0 28 7 19 16 34 13 70 150 -34 27 59 9 28 15 30 26 11 26 30 3 3 159 0 0 29 24 9 16 33 45 68 149 -35 29 16 5 29 32 12 27 29 52 31 18 15 158 0 0 30 38 27 16 33 18 67 148 -35 30 30 30 30 46 24 28 45 48 32 30 55 157 0 0 31 50 15 16 32 52 65 147 -35 31 42 25 31 58 5 29 59 14 33 41 6 156 0 0 32 59 36 16 32 28 64 146 -36 32 51 53 33 7 20 31 10 12 34 48 50 155 0 0 34 6 32 16 32 4 62 145 -36 33 58 56 34 14 9 32 18 44 35 54 10 154 0 0 35 11 6 16 31 41 61 145 -36 35 3 36 35 18 36 33 24 53 36 57 9 153 0 0 36 13 21 16 31 19 60 144 -36 36 5 58 36 20 44 34 28 41 37 57 51 152 0 0 37 13 20 16 30 58 58 143 -36 37 6 3 37 20 36 35 30 12 38 56 18 151 0 0 38 11 7 16 30 38 57 142 -37 38 3 57 38 18 18 36 29 30 39 52 36 150 0 0 39 6 47 16 30 19 56 141 -37 38 59 43 39 13 51 37 26 38 40 46 48 149 0 0 40 0 23 16 30 0 55 140 -37 39 53 25 40 7 21 38 21 40 41 38 58 148 0 0 40 51 58 16 29 42 53 140 -37 40 45 6 40 58 50 39 14 39 42 29 10 147 0 0 41 41 38 16 29 25 52 139 -37 41 34 52 41 48 24 40 5 41 43 17 29 146 0 0 42 29 26 16 29 9 51 138 -37 42 22 45 42 36 6 40 54 48 44 3 57 145 0 0 43 15 25 16 28 53 50 137 -37 43 8 50 43 22 0 41 42 5 44 48 40 144 0 0 43 59 40 16 28 38 49 136 -37 43 53 10 44 6 10 42 27 35 45 31 40 143 0 0 44 42 15 16 28 24 48 136 -37 44 35 50 44 48 39 43 11 22 46 13 3 142 0 0 45 23 12 16 28 10 47 135 -37 45 16 52 45 29 32 43 53 30 46 52 50 141 0 0 46 2 36 16 27 57 46 134 -37 45 56 21 46 8 51 44 34 2 47 31 6 140 0 0 46 40 30 16 27 44 45 133 -37 46 34 19 46 46 40 45 13 2 48 7 54 139 0 0 47 16 57 16 27 32 44 132 -37 47 10 51 47 23 3 45 50 33 48 43 18 138 0 0 47 52 1 16 27 20 43 132 -37 47 45 59 47 58 2 46 26 39 49 17 20 137 0 0 48 25 43 16 27 9 42 131 -37 48 19 46 48 31 41 47 1 21 49 50 3 136 0 0 48 58 9 16 26 58 41 130 -36 48 52 15 49 4 2 47 34 44 50 21 31 135 0 0 49 29 19 16 26 48 40 129 -36 49 23 30 49 35 8 48 6 50 50 51 46 134 0 0 49 59 17 16 26 38 40 128 -36 49 53 32 50 5 3 48 37 43 51 20 51 133 0 0 50 28 6 16 26 28 39 128 -36 50 22 24 50 33 48 49 7 23 51 48 48 132 0 0 50 55 48 16 26 19 38 127 -36 50 50 9 51 1 26 49 35 55 52 15 40 131 0 0 51 22 24 16 26 10 37 126 -36 51 16 49 51 27 59 50 3 20 52 41 29 130 0 0 51 47 59 16 26 2 36 125 -36 51 42 27 51 53 30 50 29 41 53 6 17 129 0 0 52 12 32 16 25 53 36 124 -36 52 7 4 52 18 1 50 54 59 53 30 6 128 0 0 52 36 8 16 25 45 35 123 -35 52 30 42 52 41 33 51 19 18 53 52 58 127 0 0 52 58 47 16 25 38 34 123 -35 52 53 24 53 4 9 51 42 38 54 14 56 126 0 0 53 20 31 16 25 30 33 122 -35 53 15 11 53 25 51 52 5 3 54 36 1 125 0 0 53 41 23 16 25 23 33 121 -35 53 36 6 53 46 40 52 26 33 54 56 14 124 0 0 54 1 23 16 25 16 32 120 -35 53 56 9 54 6 38 52 47 10 55 15 38 123 0 0 54 20 34 16 25 10 31 119 -35 54 15 22 54 25 46 53 6 56 55 34 13 122 0 0 54 38 57 16 25 3 31 118 -34 54 33 47 54 44 6 53 25 53 55 52 2 121 0 0 54 56 33 16 24 57 30 117 -34 54 51 26 55 1 40 53 44 2 56 9 5 120 0 0 55 13 24 16 24 51 29 117 -34 55 8 19 55 18 29 54 1 24 56 25 25 119 0 0 55 29 30 16 24 45 29 116 -34 55 24 27 55 34 33 54 18 0 56 41 2 118 0 0 55 44 55 16 24 40 28 115 -34 55 39 54 55 49 56 54 33 53 56 55 58 117 0 0 55 59 37 16 24 34 28 114 -34 55 54 38 56 4 36 54 49 3 57 10 13 116 0 0 56 13 39 16 24 29 27 113 -33 56 8 42 56 18 36 55 3 31 57 23 49 115 0 0 56 27 1 16 24 24 26 112 -33 56 22 6 56 31 57 55 17 19 57 36 46 114 0 0 56 39 46 16 24 19 26 111 -33 56 34 52 56 44 39 55 30 26 57 49 7 113 0 0 56 51 52 16 24 14 25 111 -33 56 47 0 56 56 44 55 42 56 58 0 51 112 0 0 57 3 22 16 24 10 25 110 -33 56 58 31 57 8 12 55 54 47 58 11 59 111 0 0 57 14 16 16 24 5 24 109 -32 57 9 27 57 19 5 56 6 1 58 22 33 110 0 0 57 24 35 16 24 1 23 108 -32 57 19 47 57 29 23 56 16 39 58 32 32 109 0 0 57 34 19 16 23 57 23 107 -32 57 29 33 57 39 6 56 26 42 58 41 59 108 0 0 57 43 30 16 23 53 22 106 -32 57 38 45 57 48 16 56 36 10 58 50 52 107 0 0 57 52 8 16 23 49 22 105 -32 57 47 24 57 56 52 56 45 4 58 59 14 106 0 0 58 0 14 16 23 45 21 105 -32 57 55 30 58 4 57 56 53 25 59 7 5 105 0 0 58 7 47 16 23 42 21 104 -31 58 3 5 58 12 30 57 1 13 59 14 24 104 0 0 58 14 50 16 23 38 20 103 -31 58 10 9 58 19 31 57 8 29 59 21 14 103 0 0 58 21 21 16 23 35 19 102 -31 58 16 41 58 26 2 57 15 12 59 27 33 102 0 0 58 27 23 16 23 31 19 101 -31 58 22 43 58 32 2 57 21 25 59 33 23 101 0 0 58 32 54 16 23 28 18 100 -30 58 28 15 58 37 33 57 27 7 59 38 44 100 0 0 58 37 56 16 23 25 18 99 -30 58 33 18 58 42 34 57 32 18 59 43 36 99 0 0 58 42 28 16 23 22 17 99 -30 58 37 51 58 47 6 57 36 59 59 48 1 98 0 0 58 46 32 16 23 19 17 98 -30 58 41 55 58 51 9 57 41 10 59 51 57 97 0 0 58 50 7 16 23 17 16 97 -30 58 45 30 58 54 44 57 44 52 59 55 25 96 0 0 58 53 14 16 23 14 16 96 -29 58 48 37 58 57 50 57 48 4 59 58 26 95 0 0 58 55 52 16 23 11 15 95 -29 58 51 16 59 0 28 57 50 48 60 1 0 94 0 0 58 58 3 16 23 9 15 94 -29 58 53 27 59 2 38 57 53 2 60 3 7 93 0 0 58 59 46 16 23 6 14 93 -29 58 55 10 59 4 21 57 54 48 60 4 46 92 0 0 59 1 1 16 23 4 14 93 -29 58 56 26 59 5 36 57 56 6 60 5 59 91 0 0 59 1 49 16 23 2 13 92 -28 58 57 14 59 6 24 57 56 55 60 6 46 90 0 0 59 2 9 16 23 0 13 91 -28 58 57 34 59 6 44 57 57 15 60 7 5 89 0 0 59 2 2 16 22 58 12 90 -28 58 57 27 59 6 37 57 57 8 60 6 59 88 0 0 59 1 27 16 22 56 12 89 -28 58 56 52 59 6 2 57 56 32 60 6 25 87 0 0 59 0 25 16 22 54 11 88 -27 58 55 50 59 5 1 57 55 28 60 5 25 86 0 0 58 58 56 16 22 52 10 87 -27 58 54 20 59 3 31 57 53 56 60 3 59 85 0 0 58 56 59 16 22 50 10 87 -27 58 52 23 59 1 35 57 51 56 60 2 6 84 0 0 58 54 35 16 22 49 9 86 -27 58 49 59 58 59 11 57 49 27 59 59 46 83 0 0 58 51 43 16 22 47 9 85 -26 58 47 6 58 56 19 57 46 29 59 57 0 82 0 0 58 48 23 16 22 46 8 84 -26 58 43 46 58 53 0 57 43 3 59 53 46 81 0 0 58 44 35 16 22 44 8 83 -26 58 39 57 58 49 12 57 39 8 59 50 5 80 0 0 58 40 19 16 22 43 7 82 -26 58 35 41 58 44 57 57 34 44 59 45 57 79 0 0 58 35 34 16 22 42 7 81 -25 58 30 56 58 40 13 57 29 50 59 41 21 78 0 0 58 30 21 16 22 40 6 81 -25 58 25 42 58 35 0 57 24 28 59 36 18 77 0 0 58 24 39 16 22 39 6 80 -25 58 19 59 58 29 19 57 18 35 59 30 46 76 0 0 58 18 27 16 22 38 5 79 -25 58 13 47 58 23 8 57 12 12 59 24 47 75 0 0 58 11 46 16 22 38 5 78 -24 58 7 5 58 16 28 57 5 19 59 18 18 74 0 0 58 4 35 16 22 37 4 77 -24 57 59 53 58 9 18 56 57 55 59 11 20 73 0 0 57 56 54 16 22 36 4 76 -24 57 52 10 58 1 38 56 49 59 59 3 53 72 0 0 57 48 42 16 22 36 3 75 -24 57 43 57 57 53 26 56 41 32 58 55 56 71 0 0 57 39 58 16 22 35 2 75 -23 57 35 12 57 44 44 56 32 33 58 47 28 70 0 0 57 30 43 16 22 35 2 74 -23 57 25 56 57 35 30 56 23 1 58 38 30 69 0 0 57 20 55 16 22 34 1 73 -23 57 16 7 57 25 44 56 12 55 58 29 0 68 0 0 57 10 35 16 22 34 1 72 -22 57 5 45 57 15 24 56 2 16 58 18 58 67 0 0 56 59 41 16 22 34 0 71 -22 56 54 50 57 4 32 .. .. .. 58 8 24 Uncertainty in time = +/- 20 secs Prediction of 2012 Aug 5.0 Data for the target star ------------------------ * name: HIP 18477 * constellation : Taurus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 03 56 55.4597 DE: +10 18 50.805 * position source: mpos:UCAC2 pm:UCAC2 plx:HIP2 * standard error: RA,DE ["]: ( .024, .026 ) * V mag [mag]: 9.4 * B mag [mag]: 10.0 * Apparent position with proper motion RA(deg): 59.4120320770 DE(deg): 10.3514928740 * Equation of equinoxes (radians) : 0.000065625795556 * Diameter [mas]: 0 * remarks:tyc pm issue Data for the minor planet ------------------------- * general information: (number) name: (2907) Nekrasov approx. diameter [km]: 17 approx. diameter ["]: .011 distance from Earth [AU]: 2.13100 * orbital information: orbit source: Preston date of fit: 2012 Apr 08 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 942 number of rejected observations: 29 time covered by the observations: 1954 Oct 25 - 2011 Oct 23 1 sigma uncertainty ellipse (major, minor, PA): 0.074, 0.041, 82° remarks: * orbital elements for (2907) Nekrasov : Mean anomaly = 22.71914356 deg Arg. of pericenter = 201.15274358 deg Long. of node = 172.64880475 deg Inclination = 10.20167638 deg Eccentricity = 0.09348082 Semimajor axis = 3.01794741 AU Perihelion dist = 2.73582720 AU Mag: H = 11.64, G = 0.15 Epoch of elements : MJD 56191.69500000 TDT (2012 Sep 21.695) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 21 2907 Nekrasov 16h 40.1m UT 9.4 3 56 55.460 10 18 50.80HIP 18477 10.0 16.3 17 2.8 2.131 0.536 -11.56 168.2348 10.317 -71.82 0.36 16.6691 0.03837 0.02780 1.92252 -2.80011 -0.00493 -0.00054 2000 22.4005002012 920.00000201.152744172.648805 10.2016760.09348082 3.0179474 2.735827211.5 5.00.15 RATE 1.8799080 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.078 0.048 83 7.58 0.072 0 0-3 5 056144.0020120921__18477 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Aug 05, 22:37 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org