IOTA/IOTA-ES occultation update for (691) Lehigh / TYC 6902-01304-1 event on 2012 Nov 06, 18:57 UT Visible from Japan, Taiwan Summary ------- On 2012 Nov 06 UT, the 86 km diameter asteroid (691) Lehigh will occult a 11.8 mag star in the constellation Sagittarius for observers along a path across Japan, Taiwan. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.2 mag to 14.9 mag (the magnitude of the asteroid) for at most 3.2 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: 75 * date and approx. time of event: 2012 Nov 06, 09:56 - 2012 Nov 06, 09:57 UT * geocentric midpoint of event [JD]: 2456237.9131125 * magnitude of target star: 11.8 * magnitude drop [mag]: 3.2 * estimated maximum duration [s]: 3.2 * Moon: 56 % sunlit, 159° distance * Sun: 69° distance * rough path description: Japan, Taiwan The occultation path -------------------- * approximate projected width [km]: 122 * 1 sigma uncertainty interval [path widths]: +/- 0.76 * 1 sigma uncertainty interval [seconds]: +/- 2.2 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .030 +/- .029) * 1 sigma uncertainty ellipse (major, minor, PA): ( .030", .029", 91° ) * approx speed of asteroid's shadow [km/s]: 27.1607 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6902-01304-1 by 691 Lehigh on 2012 Nov 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 ' " Longitude Longitude Longitude Longitude 153 24 49 46 0 0 9 57 36 1 224 -37 154 30 32 152 18 46 ... .. .. 150 37 36 152 1 24 45 0 0 9 57 36 2 223 -36 153 6 24 150 56 2 ... .. .. 149 15 52 150 38 12 44 0 0 9 57 36 3 222 -35 151 42 34 149 33 26 ... .. .. 147 54 8 149 15 4 43 0 0 9 57 35 5 221 -35 150 18 54 148 10 49 ... .. .. 146 32 15 147 51 54 42 0 0 9 57 34 6 220 -34 148 55 16 146 48 5 150 30 46 145 10 7 146 28 32 41 0 0 9 57 33 8 219 -33 147 31 31 145 25 4 149 6 24 143 47 35 145 4 52 40 0 0 9 57 32 9 218 -32 146 7 33 144 1 40 147 41 55 142 24 31 143 40 44 39 0 0 9 57 31 11 217 -31 144 43 13 142 37 43 146 17 12 141 0 48 142 16 2 38 0 0 9 57 29 12 216 -30 143 18 22 141 13 6 144 52 6 139 36 15 140 50 35 37 0 0 9 57 27 14 215 -29 141 52 53 139 47 40 143 26 28 138 10 45 139 24 15 36 0 0 9 57 25 15 214 -28 140 26 36 138 21 15 142 0 11 136 44 8 137 56 53 35 0 0 9 57 22 17 213 -26 138 59 22 136 53 42 140 33 6 135 16 13 136 28 19 34 0 0 9 57 20 18 212 -25 137 31 2 135 24 51 139 5 2 133 46 49 134 58 21 33 0 0 9 57 17 20 211 -24 136 1 25 133 54 29 137 35 50 132 15 44 133 26 48 32 0 0 9 57 13 21 210 -23 134 30 19 132 22 25 136 5 20 130 42 45 131 53 26 31 0 0 9 57 10 23 209 -21 132 57 32 130 48 24 134 33 19 129 7 35 130 18 1 30 0 0 9 57 6 24 208 -20 131 22 50 129 12 10 132 59 35 127 29 57 128 40 15 29 0 0 9 57 2 26 207 -18 129 45 58 127 33 26 131 23 53 125 49 32 126 59 50 28 0 0 9 56 57 27 205 -16 128 6 36 125 51 51 129 45 57 124 5 56 125 16 23 27 0 0 9 56 52 29 204 -15 126 24 25 124 7 0 128 5 28 122 18 40 123 29 29 26 0 0 9 56 47 30 203 -13 124 39 2 122 18 25 126 22 7 120 27 12 121 38 35 25 0 0 9 56 41 32 201 -11 122 49 56 120 25 31 124 35 27 118 30 50 119 43 4 24 0 0 9 56 34 33 200 -9 120 56 34 118 27 36 122 44 59 116 28 42 117 42 7 23 0 0 9 56 27 35 198 -7 118 58 15 116 23 45 120 50 8 114 19 42 Latitude Latitude Latitude Latitude 116 0 0 22 11 38 9 56 21 36 196 -5 21 34 51 22 48 51 20 39 45 23 46 21 115 0 0 21 44 12 9 56 18 37 195 -4 21 7 37 22 21 13 20 12 49 23 18 22 114 0 0 21 17 31 9 56 14 38 194 -3 20 41 8 21 54 19 19 46 38 22 51 9 113 0 0 20 51 35 9 56 10 38 193 -2 20 15 24 21 28 11 19 21 11 22 24 42 112 0 0 20 26 25 9 56 6 39 192 -1 19 50 25 21 2 49 18 56 28 21 59 1 111 0 0 20 2 0 9 56 3 39 191 0 19 26 11 20 38 13 18 32 30 21 34 6 Uncertainty in time = +/- 3 secs Prediction of 2012 Sep 27.0 Data for the target star ------------------------ * name: TYC 6902-01304-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 43 49.8919 DE: -29 47 44.486 * position source: mpos:UCAC4 pm:UCAC4 * standard error: RA,DE ["]: ( .026, .027 ) * V mag [mag]: 11.8 * B mag [mag]: 12.8 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (691) Lehigh approx. diameter [km]: 86 approx. diameter ["]: .038 distance from Earth [AU]: 3.12100 * orbital information: orbit source: Preston date of fit: 2012 Sep 26 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 894 number of rejected observations: 52 time covered by the observations: 1914 Nov 21 - 2012 Sep 17 1 sigma uncertainty ellipse (major, minor, PA): 0.015, 0.010, 94° remarks: * orbital elements for (691) Lehigh : Mean anomaly = 293.20430803 deg Arg. of pericenter = 303.88050158 deg Long. of node = 88.18823385 deg Inclination = 13.02735634 deg Eccentricity = 0.11885124 Semimajor axis = 3.01226434 AU Perihelion dist = 2.65425299 AU Mag: H = 9.16, G = 0.15 Epoch of elements : MJD 56237.79000000 TDT (2012 Nov 06.790) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Nov 6 691 Lehigh 9h 54.9m UT 11.8 19 43 49.892-29 47 44.49TYC 6902-01304-1 12.8 14.9 86 3.2 3.121 3.259 8.18 101.2160 -29.797 27.20 -16.16 9.9147 -0.13014 0.69900 15.05302 2.90224 0.00545 0.00066 2000 291.73571320121030.00000303.880502 88.188234 13.0273560.11885124 3.0122643 2.6542530 9.2 5.00.15 RATE 1.8852310 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.030 0.029 91 1.76 0.029 0 0-1 4 056197.0020121106_1304-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Sep 26, 23:18 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org