IOTA/IOTA-ES occultation update for (12740) 1992 EX8 / HIP 31128 event on 2008 Jan 04, 08:15 UT Visible from NE USA, Canada Summary ------- On 2008 Jan 04 UT, the 12 km diameter asteroid (12740) 1992 EX8 will occult a 7.6 mag star in the constellation Monoceros for observers along a path across NE USA, Canada. In the case of an occultation, the combined light of the asteroid and the star will drop by 7.9 mag to 15.5 mag (the magnitude of the asteroid) for at most 1.0 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: . The event at a glimpse ---------------------- * Rank: 9 * date and approx. time of event: 2008 Jan 04, 08:11 - 2008 Jan 04, 08:20 UT * magnitude of target star: 7.6 * magnitude drop [mag]: 7.9 * estimated maximum duration [s]: 1.0 * Moon: 15 % sunlit, 133° distance * Sun: 161° distance * rough path description: NE USA, Canada The occultation path -------------------- * approximate projected width [km]: 23 * 1 sigma uncertainty interval [path widths]: +/- 7.46 * 1 sigma uncertainty interval [seconds]: +/- 9.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .118 +/- .065) * 1 sigma uncertainty ellipse (major, minor, PA): ( .118", .064", 84° ) * approx speed of asteroid's shadow [km/s]: 11.8187 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of HIP 31128 by 12740 1992 EX8 on 2008 Jan 04 Centre Star Star Sun Path Limit1 Path Limit2 Error Limit1 Error Limit2 E. Longitude Latitude U.T. Alt Az Alt o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " o ' " o ' " o ' " o ' " Longitude Latitude Longitude Latitude Longitude Latitude Longitude Latitude ... .. .. .. .. .. .. .. .. .. .. .. ... .. .. .. .. .. ... .. .. .. .. .. - 44 47 22 33 56 52 ... .. .. .. .. .. - 41 9 43 34 57 9 8 11 16 5 272 -20 - 41 44 20 34 56 37 - 40 31 47 34 57 24 - 47 35 23 34 34 1 ... .. .. .. .. .. - 44 53 54 35 39 43 8 11 23 8 270 -23 - 45 16 59 35 38 7 - 44 29 55 35 41 14 - 49 53 45 35 8 34 ... .. .. .. .. .. - 47 37 10 36 16 54 8 11 30 11 268 -26 - 47 55 53 36 14 53 - 47 17 58 36 18 52 - 51 54 30 35 41 35 - 40 48 1 36 39 12 - 49 52 40 36 51 40 8 11 37 12 267 -27 - 50 8 58 36 49 25 - 49 36 4 36 53 53 - 53 43 16 36 13 37 - 44 34 15 37 22 26 - 51 51 25 37 25 0 8 11 44 14 266 -29 - 52 6 6 37 22 36 - 51 36 29 37 27 24 - 55 23 15 36 44 54 - 47 17 44 38 0 10 - 53 38 37 37 57 23 8 11 51 15 264 -31 - 53 52 11 37 54 51 - 53 24 53 37 59 55 - 56 56 25 37 15 40 - 49 33 5 38 35 28 - 55 17 20 38 29 5 8 11 58 16 263 -32 - 55 30 1 38 26 27 - 55 4 29 38 31 43 - 58 24 9 37 46 0 - 51 31 31 39 9 19 - 56 49 26 39 0 16 8 12 5 18 262 -33 - 57 1 26 38 57 33 - 56 37 17 39 2 59 - 59 47 25 38 16 2 - 53 18 22 39 42 14 - 58 16 14 39 31 4 8 12 12 19 261 -34 - 58 27 41 39 28 16 - 58 4 40 39 33 52 - 61 6 56 38 45 47 - 54 56 41 40 14 29 - 59 38 40 40 1 34 8 12 19 20 260 -35 - 59 49 40 39 58 42 - 59 27 34 40 4 26 - 62 23 16 39 15 21 - 56 28 23 40 46 14 - 60 57 27 40 31 50 8 12 25 20 259 -36 - 61 8 4 40 28 54 - 60 46 44 40 34 45 - 63 36 51 39 44 45 - 57 54 46 41 17 36 - 62 13 7 41 1 55 8 12 32 21 258 -37 - 62 23 24 40 58 56 - 62 2 44 41 4 53 - 64 48 3 40 14 1 - 59 16 48 41 48 41 - 63 26 5 41 31 51 8 12 39 22 257 -38 - 63 36 6 41 28 49 - 63 15 59 41 34 53 - 65 57 9 40 43 12 - 60 35 11 42 19 34 - 64 36 42 42 1 41 8 12 46 23 256 -39 - 64 46 28 41 58 36 - 64 26 51 42 4 46 - 67 4 23 41 12 18 - 61 50 26 42 50 16 - 65 45 16 42 31 27 8 12 53 23 255 -40 - 65 54 50 42 28 19 - 65 35 38 42 34 34 - 68 9 58 41 41 21 - 63 3 0 43 20 51 - 66 52 1 43 1 9 8 13 0 24 254 -40 - 67 1 23 42 57 59 - 66 42 34 43 4 20 - 69 14 5 42 10 23 - 64 13 14 43 51 21 - 67 57 9 43 30 50 8 13 7 25 253 -41 - 68 6 21 43 27 37 - 67 47 52 43 34 3 - 70 16 53 42 39 24 - 65 21 24 44 21 47 - 69 0 50 44 0 30 8 13 14 25 252 -42 - 69 9 53 43 57 14 - 68 51 42 44 3 46 - 71 18 30 43 8 25 - 66 27 46 44 52 12 - 70 3 13 44 30 11 8 13 21 26 251 -42 - 70 12 9 44 26 52 - 69 54 13 44 33 29 - 72 19 3 43 37 27 - 67 32 30 45 22 36 - 71 4 27 44 59 53 8 13 28 26 250 -43 - 71 13 17 44 56 32 - 70 55 34 45 3 14 - 73 18 39 44 6 31 - 68 35 48 45 53 1 - 72 4 39 45 29 37 8 13 35 27 248 -44 - 72 13 22 45 26 14 - 71 55 52 45 33 1 - 74 17 22 44 35 37 - 69 37 49 46 23 27 - 73 3 54 45 59 25 8 13 42 27 247 -44 - 73 12 32 45 55 59 - 72 55 13 46 2 51 - 75 15 19 45 4 47 - 70 38 41 46 53 57 - 74 2 19 46 29 17 8 13 49 27 246 -45 - 74 10 52 46 25 48 - 73 53 42 46 32 45 - 76 12 34 45 34 1 - 71 38 31 47 24 30 - 74 59 58 46 59 13 8 13 56 28 245 -45 - 75 8 27 46 55 42 - 74 51 26 47 2 44 - 77 9 12 46 3 19 - 72 37 24 47 55 8 - 75 56 57 47 29 14 8 14 3 28 244 -46 - 76 5 22 47 25 41 - 75 48 28 47 32 48 - 78 5 16 46 32 42 - 73 35 27 48 25 52 - 76 53 19 47 59 22 8 14 10 28 243 -46 - 77 1 41 47 55 46 - 76 44 54 48 2 58 - 79 0 50 47 2 11 - 74 32 45 48 56 42 - 77 49 9 48 29 37 8 14 17 29 242 -46 - 77 57 28 48 25 58 - 77 40 46 48 33 15 - 79 55 58 47 31 47 - 75 29 23 49 27 39 - 78 44 30 48 59 59 8 14 24 29 241 -47 - 78 52 47 48 56 18 - 78 36 10 49 3 40 - 80 50 43 48 1 29 - 76 25 24 49 58 44 - 79 39 26 49 30 29 8 14 31 29 240 -47 - 79 47 41 49 26 45 - 79 31 8 49 34 12 - 81 45 8 48 31 19 - 77 20 54 50 29 58 - 80 34 1 50 1 8 8 14 38 30 239 -47 - 80 42 14 49 57 21 - 80 25 44 50 4 54 - 82 39 17 49 1 16 - 78 15 55 51 1 21 - 81 28 17 50 31 56 8 14 45 30 238 -48 - 81 36 29 50 28 7 - 81 20 2 50 35 45 - 83 33 11 49 31 23 - 79 10 31 51 32 54 - 82 22 18 51 2 54 8 14 52 30 237 -48 - 82 30 29 50 59 2 - 82 14 4 51 6 46 - 84 26 55 50 1 38 - 80 4 47 52 4 39 - 83 16 6 51 34 3 8 14 58 30 236 -48 - 83 24 16 51 30 8 - 83 7 53 51 37 57 - 85 20 30 50 32 4 - 80 58 44 52 36 35 - 84 9 45 52 5 23 8 15 5 30 235 -48 - 84 17 55 52 1 25 - 84 1 32 52 9 21 - 86 14 1 51 2 39 - 81 52 27 53 8 43 - 85 3 17 52 36 55 8 15 12 30 233 -49 - 85 11 27 52 32 55 - 84 55 5 52 40 56 - 87 7 28 51 33 26 - 82 45 58 53 41 5 - 85 56 46 53 8 40 8 15 19 30 232 -49 - 86 4 56 53 4 37 - 85 48 33 53 12 44 - 88 0 55 52 4 24 - 83 39 20 54 13 41 - 86 50 14 53 40 39 8 15 26 31 231 -49 - 86 58 25 53 36 32 - 86 42 1 53 44 46 - 88 54 25 52 35 34 - 84 32 36 54 46 32 - 87 43 45 54 12 51 8 15 33 31 230 -49 - 87 51 56 54 8 42 - 87 35 31 54 17 2 - 89 48 1 53 6 58 - 85 25 50 55 19 38 - 88 37 20 54 45 19 8 15 40 31 229 -49 - 88 45 32 54 41 6 - 88 29 5 54 49 33 - 90 41 45 53 38 34 - 86 19 4 55 53 2 - 89 31 3 55 18 3 8 15 47 31 228 -49 - 89 39 16 55 13 46 - 89 22 47 55 22 20 - 91 35 40 54 10 25 - 87 12 21 56 26 43 - 90 24 57 55 51 3 8 15 54 31 227 -49 - 90 33 12 55 46 43 - 90 16 40 55 55 24 - 92 29 49 54 42 31 - 88 5 45 57 0 43 - 91 19 6 56 24 21 8 16 1 31 225 -49 - 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99 56 0 61 35 3 - 99 38 36 61 45 14 -101 57 6 60 20 18 - 97 18 36 63 2 19 -100 47 32 62 17 24 8 17 11 29 213 -48 -100 56 16 62 12 14 -100 38 44 62 22 36 -102 58 0 60 56 8 - 98 17 24 63 41 11 -101 48 52 62 55 12 8 17 18 29 212 -47 -101 57 39 62 49 56 -101 40 0 63 0 30 -104 0 1 61 32 25 - 99 17 14 64 20 42 -102 51 26 63 33 34 8 17 25 28 211 -47 -103 0 17 63 28 11 -102 42 30 63 38 58 -105 3 18 62 9 12 -100 18 13 65 0 52 -103 55 24 64 12 32 8 17 31 28 209 -47 -104 4 19 64 7 2 -103 46 23 64 18 2 -106 7 58 62 46 29 -101 20 31 65 41 45 -105 0 55 64 52 8 8 17 38 28 208 -46 -105 9 55 64 46 31 -104 51 50 64 57 46 -107 14 11 63 24 18 -102 24 18 66 23 24 -106 8 13 65 32 25 8 17 45 27 207 -46 -106 17 16 65 26 40 -105 59 3 65 38 10 -108 22 9 64 2 42 -103 29 46 67 5 52 -107 17 29 66 13 26 8 17 52 27 205 -45 -107 26 37 66 7 33 -107 8 15 66 19 19 -109 32 2 64 41 42 -104 37 10 67 49 13 -108 29 0 66 55 13 8 17 59 26 204 -45 -108 38 12 66 49 12 -108 19 42 67 1 16 -110 44 5 65 21 21 -105 46 46 68 33 32 -109 43 5 67 37 51 8 18 6 26 202 -44 -109 52 20 67 31 41 -109 33 43 67 44 3 -111 58 34 66 1 41 -106 58 54 69 18 53 -111 0 4 68 21 23 8 18 13 25 201 -44 -111 9 22 68 15 3 -110 50 38 68 27 45 -113 15 48 66 42 46 -108 13 58 70 5 22 -112 20 23 69 5 54 8 18 20 25 199 -43 -112 29 44 68 59 22 -112 10 55 69 12 27 -114 36 8 67 24 37 -109 32 27 70 53 6 -113 44 35 69 51 28 8 18 27 24 198 -43 -113 53 58 69 44 45 -113 35 5 69 58 13 -116 0 1 68 7 19 -110 54 58 71 42 11 -115 13 18 70 38 11 8 18 34 24 196 -42 -115 22 40 70 31 15 -115 3 47 70 45 9 -117 27 58 68 50 56 -112 22 16 72 32 46 -116 47 19 71 26 9 8 18 41 23 194 -41 -116 56 39 71 18 59 -116 37 50 71 33 22 -119 0 36 69 35 31 -113 55 20 73 25 2 -118 27 38 72 15 30 8 18 48 22 192 -40 -118 36 52 72 8 4 -118 18 15 72 22 58 -120 38 41 70 21 9 -115 35 29 74 19 9 -120 15 34 73 6 22 8 18 55 22 190 -40 -120 24 38 72 58 38 -120 6 21 73 14 8 -122 23 10 71 7 55 -117 24 29 75 15 24 -122 12 47 73 58 54 8 19 2 21 188 -39 -122 21 33 73 50 51 -122 3 51 74 6 59 -124 15 14 71 55 55 -119 24 44 76 14 2 -124 21 34 74 53 18 8 19 9 20 186 -38 -124 29 51 74 44 53 -124 13 6 75 1 46 -126 16 24 72 45 17 -121 39 49 77 15 26 -126 45 3 75 49 47 8 19 16 19 184 -37 -126 52 35 75 40 57 -126 37 20 75 58 40 -128 28 40 73 36 6 -124 15 3 78 20 2 -129 27 41 76 48 36 8 19 23 18 181 -36 -129 34 2 76 39 18 -129 21 10 76 57 58 -130 54 37 74 28 31 -127 19 0 79 28 26 -132 36 5 77 50 3 8 19 30 17 177 -35 -132 40 33 77 40 13 -132 31 32 78 0 0 -133 37 52 75 22 41 -131 6 28 80 41 19 -136 20 33 78 54 29 8 19 37 16 174 -34 -136 21 52 78 44 0 -136 19 14 79 5 5 -136 43 24 76 18 45 -136 5 29 81 59 36 -140 57 59 80 2 12 8 19 44 15 169 -32 -140 53 55 79 50 58 -141 2 21 80 13 35 -140 18 28 77 16 52 -143 17 4 83 24 12 -146 58 27 81 13 25 8 19 51 13 163 -31 -146 44 31 81 1 19 -147 13 24 81 25 42 -144 33 59 78 17 8 -155 22 5 84 54 56 -155 20 20 82 27 48 8 19 58 12 154 -29 -154 46 46 82 14 46 -155 56 49 82 41 1 -149 47 13 79 19 33 178 43 25 86 21 51 -168 10 3 83 42 46 8 20 4 10 141 -27 -166 52 54 83 29 7 -169 35 36 83 56 34 -156 26 52 80 23 47 118 24 45 86 14 57 169 36 57 84 46 38 8 20 11 8 119 -25 172 39 16 84 34 39 166 10 43 84 58 7 -165 24 3 81 28 34 ... .. .. .. .. .. 128 19 36 84 42 6 8 20 18 4 78 -21 135 4 29 84 45 57 120 39 16 84 31 44 -178 15 27 82 30 8 ... .. .. .. .. .. ... .. .. .. .. .. .. .. .. .. .. .. ... .. .. .. .. .. ... .. .. .. .. .. 161 47 34 83 16 22 ... .. .. .. .. .. Data for the target star ------------------------ * name: HIP 31128 * constellation : Monoceros * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 06 31 52.5329 DE: +05 01 59.186 * position source: mpos:HIP pm:HIP plx:HIP * standard error: RA,DE ["]: ( .016, .013 ) * V mag [mag]: 7.6 * B mag [mag]: 7.7 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (12740) 1992 EX8 approx. diameter [km]: 12 approx. diameter ["]: .011 distance from Earth [AU]: 1.48400 * orbital information: orbit source: Preston date of fit: 2008 Jan 02 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 574 number of rejected observations: 4 time covered by the observations: 1977 Aug 18 - 2007 Dec 15 1 sigma uncertainty ellipse (major, minor, PA): 0.117, 0.063, 84° remarks: * orbital elements for (12740) 1992 EX8 : Mean anomaly = 356.76415547 deg Arg. of pericenter = 318.93282918 deg Long. of node = 143.94139895 deg Inclination = 15.68318898 deg Eccentricity = 0.05254198 Semimajor axis = 2.57003402 AU Perihelion dist = 2.43499935 AU Mag: H = 12.20, G = 0.15 Epoch of elements : MJD 54469.34400000 TDT (2008 Jan 04.344) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Jan 04 12740 1992 EX8 8h 15.8m UT 7.6 6 31 52.533 5 1 59.19HIP 31128 7.7 15.5 12 1.0 1.484 -2.396 16.79 -129.304 5.030 57.22 -22.77 8.2631 .36424 .77686 -6.04037 2.83077 0.00058 0.00179 2000 354.52889220071226.00000318.932829143.941399 15.6831890.052541982.570034022.4349993512.25 0.15 RATE 2.3921900 .0000000 .0000000 .0000000 .00000000 .00000000 .00000000 Meas 0.118 0.064 84.1 8.460 0.083 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Jan 02, 22:57 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org