IOTA/IOTA-ES occultation update for (923) Herluga / TYC 4664-00689-1 event on 2012 Dec 22, 04:36 UT Visible from Canada, NW USA Summary ------- On 2012 Dec 22 UT, the 35 km diameter asteroid (923) Herluga will occult a 10.7 mag star in the constellation Pisces for observers along a path across Canada, NW USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 5.0 mag to 15.7 mag (the magnitude of the asteroid) for at most 1.9 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: 40 * date and approx. time of event: 2012 Dec 22, 04:35 - 2012 Dec 22, 04:40 UT * geocentric midpoint of event [JD]: 2456283.6920625 * magnitude of target star: 10.7 * magnitude drop [mag]: 5.0 * estimated maximum duration [s]: 1.9 * Moon: 68 % sunlit, 21° distance * Sun: 92° distance * rough path description: Canada, NW USA The occultation path -------------------- * approximate projected width [km]: 47 * 1 sigma uncertainty interval [path widths]: +/- 1.66 * 1 sigma uncertainty interval [seconds]: +/- 3.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .048 +/- .043) * 1 sigma uncertainty ellipse (major, minor, PA): ( .048", .043", 90° ) * approx speed of asteroid's shadow [km/s]: 18.3314 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 4664-00689-1 by 923 Herluga on 2012 Dec 22 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 -177 0 0 36 26 24 4 35 33 47 148 -1 36 13 26 36 39 25 35 30 42 37 22 56 -176 0 0 36 36 52 4 35 38 47 150 -1 36 23 54 36 49 53 35 41 9 37 33 25 -175 0 0 36 47 26 4 35 43 47 151 -2 36 34 28 37 0 28 35 51 41 37 44 1 -174 0 0 36 58 7 4 35 48 47 153 -3 36 45 8 37 11 8 36 2 20 37 54 43 -173 0 0 37 8 52 4 35 53 48 154 -4 36 55 53 37 21 54 36 13 4 38 5 30 -172 0 0 37 19 43 4 35 58 48 156 -5 37 6 44 37 32 46 36 23 54 38 16 23 -171 0 0 37 30 40 4 36 3 48 157 -5 37 17 40 37 43 42 36 34 49 38 27 20 -170 0 0 37 41 41 4 36 8 48 159 -6 37 28 40 37 54 44 36 45 48 38 38 23 -169 0 0 37 52 46 4 36 13 48 160 -7 37 39 46 38 5 49 36 56 53 38 49 30 -168 0 0 38 3 56 4 36 18 48 162 -8 37 50 55 38 17 0 37 8 1 39 0 41 -167 0 0 38 15 10 4 36 23 48 164 -9 38 2 9 38 28 14 37 19 14 39 11 56 -166 0 0 38 26 28 4 36 28 48 165 -9 38 13 26 38 39 32 37 30 31 39 23 15 -165 0 0 38 37 49 4 36 33 48 167 -10 38 24 47 38 50 53 37 41 51 39 34 37 -164 0 0 38 49 13 4 36 38 48 168 -11 38 36 11 39 2 18 37 53 14 39 46 3 -163 0 0 39 0 40 4 36 43 48 170 -12 38 47 38 39 13 45 38 4 40 39 57 31 -162 0 0 39 12 10 4 36 48 48 171 -13 38 59 8 39 25 15 38 16 9 40 9 2 -161 0 0 39 23 43 4 36 53 48 173 -13 39 10 40 39 36 48 38 27 41 40 20 35 -160 0 0 39 35 17 4 36 58 48 174 -14 39 22 14 39 48 23 38 39 14 40 32 11 -159 0 0 39 46 54 4 37 3 48 176 -15 39 33 50 39 59 59 38 50 50 40 43 48 -158 0 0 39 58 31 4 37 8 48 178 -16 39 45 28 40 11 37 39 2 27 40 55 26 -157 0 0 40 10 11 4 37 13 48 179 -17 39 57 7 40 23 17 39 14 6 41 7 6 -156 0 0 40 21 51 4 37 17 47 181 -18 40 8 47 40 34 57 39 25 45 41 18 47 -155 0 0 40 33 32 4 37 22 47 182 -18 40 20 28 40 46 38 39 37 26 41 30 29 -154 0 0 40 45 13 4 37 27 47 184 -19 40 32 10 40 58 20 39 49 7 41 42 11 -153 0 0 40 56 55 4 37 32 47 185 -20 40 43 52 41 10 2 40 0 48 41 53 53 -152 0 0 41 8 37 4 37 36 46 186 -21 40 55 33 41 21 44 40 12 30 42 5 35 -151 0 0 41 20 19 4 37 41 46 188 -21 41 7 15 41 33 25 40 24 11 42 17 17 -150 0 0 41 32 0 4 37 46 46 189 -22 41 18 56 41 45 6 40 35 52 42 28 58 -149 0 0 41 43 40 4 37 50 45 191 -23 41 30 36 41 56 46 40 47 32 42 40 38 -148 0 0 41 55 19 4 37 55 45 192 -24 41 42 15 42 8 26 40 59 11 42 52 17 -147 0 0 42 6 57 4 37 59 45 194 -25 41 53 53 42 20 3 41 10 49 43 3 55 -146 0 0 42 18 33 4 38 4 44 195 -25 42 5 29 42 31 40 41 22 25 43 15 31 -145 0 0 42 30 7 4 38 8 44 196 -26 42 17 4 42 43 14 41 34 0 43 27 6 -144 0 0 42 41 40 4 38 12 44 198 -27 42 28 36 42 54 47 41 45 33 43 38 38 -143 0 0 42 53 10 4 38 17 43 199 -28 42 40 6 43 6 17 41 57 3 43 50 8 -142 0 0 43 4 38 4 38 21 43 200 -28 42 51 34 43 17 44 42 8 31 44 1 35 -141 0 0 43 16 3 4 38 25 42 201 -29 43 2 59 43 29 9 42 19 57 44 13 0 -140 0 0 43 27 25 4 38 29 42 203 -30 43 14 22 43 40 31 42 31 19 44 24 21 -139 0 0 43 38 44 4 38 34 41 204 -31 43 25 41 43 51 50 42 42 39 44 35 40 -138 0 0 43 49 59 4 38 38 41 205 -31 43 36 56 44 3 5 42 53 55 44 46 54 -137 0 0 44 1 11 4 38 42 40 206 -32 43 48 8 44 14 17 43 5 8 44 58 6 -136 0 0 44 12 19 4 38 46 40 208 -33 43 59 16 44 25 25 43 16 16 45 9 13 -135 0 0 44 23 23 4 38 50 39 209 -34 44 10 21 44 36 29 43 27 21 45 20 16 -134 0 0 44 34 23 4 38 53 39 210 -34 44 21 21 44 47 28 43 38 22 45 31 15 -133 0 0 44 45 18 4 38 57 38 211 -35 44 32 16 44 58 23 43 49 18 45 42 9 -132 0 0 44 56 9 4 39 1 38 212 -36 44 43 7 45 9 14 44 0 10 45 52 59 -131 0 0 45 6 55 4 39 5 37 213 -37 44 53 53 45 19 59 44 10 57 46 3 44 -130 0 0 45 17 36 4 39 8 37 214 -37 45 4 34 45 30 40 44 21 39 46 14 23 -129 0 0 45 28 11 4 39 12 36 215 -38 45 15 10 45 41 15 44 32 16 46 24 58 -128 0 0 45 38 42 4 39 15 36 217 -39 45 25 41 45 51 45 44 42 47 46 35 27 -127 0 0 45 49 7 4 39 19 35 218 -39 45 36 6 46 2 10 44 53 13 46 45 50 -126 0 0 45 59 26 4 39 22 35 219 -40 45 46 25 46 12 29 45 3 34 46 56 8 -125 0 0 46 9 39 4 39 25 34 220 -41 45 56 39 46 22 41 45 13 48 47 6 20 -124 0 0 46 19 46 4 39 29 33 221 -41 46 6 46 46 32 48 45 23 57 47 16 25 -123 0 0 46 29 47 4 39 32 33 222 -42 46 16 48 46 42 49 45 33 59 47 26 25 -122 0 0 46 39 42 4 39 35 32 223 -43 46 26 43 46 52 43 45 43 55 47 36 18 -121 0 0 46 49 30 4 39 38 32 224 -43 46 36 31 47 2 31 45 53 45 47 46 5 -120 0 0 46 59 11 4 39 41 31 225 -44 46 46 13 47 12 12 46 3 28 47 55 45 -119 0 0 47 8 46 4 39 44 30 226 -45 46 55 48 47 21 47 46 13 5 48 5 18 -118 0 0 47 18 14 4 39 47 30 227 -45 47 5 17 47 31 14 46 22 34 48 14 44 -117 0 0 47 27 35 4 39 50 29 227 -46 47 14 38 47 40 35 46 31 57 48 24 3 -116 0 0 47 36 49 4 39 52 29 228 -46 47 23 52 47 49 48 46 41 12 48 33 15 -115 0 0 47 45 55 4 39 55 28 229 -47 47 32 59 47 58 54 46 50 21 48 42 20 -114 0 0 47 54 55 4 39 58 27 230 -48 47 41 59 48 7 53 46 59 21 48 51 17 -113 0 0 48 3 46 4 40 0 27 231 -48 47 50 51 48 16 44 47 8 15 49 0 7 -112 0 0 48 12 30 4 40 3 26 232 -49 47 59 35 48 25 28 47 17 1 49 8 49 -111 0 0 48 21 7 4 40 5 26 233 -49 48 8 12 48 34 4 47 25 39 49 17 24 -110 0 0 48 29 35 4 40 8 25 234 -50 48 16 41 48 42 32 47 34 9 49 25 50 -109 0 0 48 37 56 4 40 10 24 235 -50 48 25 2 48 50 52 47 42 32 49 34 9 -108 0 0 48 46 8 4 40 12 24 236 -51 48 33 15 48 59 4 47 50 46 49 42 20 -107 0 0 48 54 13 4 40 14 23 236 -52 48 41 20 49 7 9 47 58 53 49 50 22 -106 0 0 49 2 10 4 40 17 22 237 -52 48 49 17 49 15 5 48 6 51 49 58 17 -105 0 0 49 9 58 4 40 19 22 238 -53 48 57 6 49 22 52 48 14 41 50 6 3 -104 0 0 49 17 38 4 40 21 21 239 -53 49 4 46 49 30 32 48 22 23 50 13 41 -103 0 0 49 25 9 4 40 23 21 240 -54 49 12 18 49 38 3 48 29 56 50 21 11 -102 0 0 49 32 32 4 40 24 20 241 -54 49 19 42 49 45 26 48 37 21 50 28 32 -101 0 0 49 39 47 4 40 26 19 242 -54 49 26 57 49 52 40 48 44 38 50 35 45 -100 0 0 49 46 53 4 40 28 19 242 -55 49 34 3 49 59 45 48 51 45 50 42 49 - 99 0 0 49 53 50 4 40 30 18 243 -55 49 41 1 50 6 42 48 58 45 50 49 44 - 98 0 0 50 0 39 4 40 31 17 244 -56 49 47 50 50 13 30 49 5 35 50 56 31 - 97 0 0 50 7 18 4 40 33 17 245 -56 49 54 30 50 20 10 49 12 17 51 3 9 - 96 0 0 50 13 49 4 40 34 16 246 -57 50 1 1 50 26 40 49 18 49 51 9 38 - 95 0 0 50 20 12 4 40 36 15 247 -57 50 7 24 50 33 2 49 25 13 51 15 58 - 94 0 0 50 26 25 4 40 37 15 247 -57 50 13 38 50 39 15 49 31 28 51 22 9 - 93 0 0 50 32 29 4 40 38 14 248 -58 50 19 42 50 45 19 49 37 34 51 28 12 - 92 0 0 50 38 24 4 40 40 14 249 -58 50 25 38 50 51 13 49 43 31 51 34 5 - 91 0 0 50 44 11 4 40 41 13 250 -58 50 31 25 50 56 59 49 49 19 51 39 50 - 90 0 0 50 49 48 4 40 42 12 251 -59 50 37 2 51 2 36 49 54 58 51 45 25 - 89 0 0 50 55 16 4 40 43 12 251 -59 50 42 31 51 8 4 50 0 28 51 50 52 - 88 0 0 51 0 35 4 40 44 11 252 -59 50 47 50 51 13 22 50 5 48 51 56 9 - 87 0 0 51 5 45 4 40 45 10 253 -60 50 53 0 51 18 32 50 11 0 52 1 17 - 86 0 0 51 10 45 4 40 46 10 254 -60 50 58 1 51 23 32 50 16 2 52 6 16 - 85 0 0 51 15 36 4 40 47 9 255 -60 51 2 53 51 28 23 50 20 54 52 11 6 - 84 0 0 51 20 18 4 40 48 9 255 -60 51 7 35 51 33 4 50 25 38 52 15 46 - 83 0 0 51 24 51 4 40 48 8 256 -60 51 12 8 51 37 37 50 30 12 52 20 17 - 82 0 0 51 29 15 4 40 49 7 257 -61 51 16 32 51 42 0 50 34 37 52 24 39 - 81 0 0 51 33 29 4 40 50 7 258 -61 51 20 46 51 46 14 50 38 53 52 28 52 - 80 0 0 51 37 34 4 40 50 6 259 -61 51 24 51 51 50 18 50 42 59 52 32 56 - 79 0 0 51 41 29 4 40 51 5 259 -61 51 28 47 51 54 13 50 46 55 52 36 50 - 78 0 0 51 45 15 4 40 51 5 260 -61 51 32 33 51 57 59 50 50 43 52 40 34 - 77 0 0 51 48 52 4 40 52 4 261 -61 51 36 10 52 1 36 .. .. .. 52 44 10 - 76 0 0 51 52 19 4 40 52 4 262 -61 51 39 38 52 5 3 .. .. .. 52 47 36 - 75 0 0 51 55 37 4 40 52 3 262 -61 51 42 56 52 8 20 .. .. .. 52 50 53 - 74 0 0 51 58 45 4 40 52 2 263 -61 51 46 5 52 11 28 .. .. .. 52 54 0 - 73 0 0 52 1 44 4 40 53 2 264 -61 51 49 4 52 14 27 .. .. .. 52 56 58 - 72 0 0 52 4 34 4 40 53 1 265 -61 51 51 54 52 17 17 .. .. .. 52 59 47 - 71 0 0 52 7 14 4 40 53 0 266 -61 51 54 34 52 19 57 .. .. .. 53 2 26 Uncertainty in time = +/- 3 secs Prediction of 2012 Dec 17.0 Data for the target star ------------------------ * name: TYC 4664-00689-1 * constellation : Pisces * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 00 15 43.3061 DE: -02 25 51.477 * position source: mpos:UCAC4 pm:UCAC4 * standard error: RA,DE ["]: ( .043, .039 ) * V mag [mag]: 10.7 * B mag [mag]: 11.1 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (923) Herluga approx. diameter [km]: 35 approx. diameter ["]: .026 distance from Earth [AU]: 1.82400 * orbital information: orbit source: Preston date of fit: 2012 Dec 16 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 925 number of rejected observations: 21 time covered by the observations: 1919 Dec 10 - 2012 Dec 11 1 sigma uncertainty ellipse (major, minor, PA): 0.021, 0.018, 92° remarks: * orbital elements for (923) Herluga : Mean anomaly = 354.57995428 deg Arg. of pericenter = 201.49441253 deg Long. of node = 197.68287030 deg Inclination = 14.47747433 deg Eccentricity = 0.19657057 Semimajor axis = 2.61439397 AU Perihelion dist = 2.10048107 AU Mag: H = 11.46, G = 0.15 Epoch of elements : MJD 56283.19200000 TDT (2012 Dec 22.192) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Dec 22 923 Herluga 4h 36.6m UT 10.7 0 15 43.306- 2 25 51.48TYC 4664-00689-1 11.1 15.7 35 1.9 1.824 3.274 8.99 -156.3549 -2.433 110.53 -23.43 4.6095 -0.11728 0.65268 10.17741 1.86437 0.00511 0.00223 2000 353.83571820121219.00000201.494413197.682870 14.4774740.19657057 2.6143940 2.100481111.5 5.00.15 RATE 2.3315650 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.048 0.043 90 2.66 0.044 0 0 1 3 056278.0020121222_0689-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Dec 16, 19:05 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org