IOTA/IOTA-ES occultation update for (1268) Libya / TYC 6123-00585-1 event on 2008 May 20, 02:05 UT Visible from W Africa, E USA Summary ------- On 2008 May 20 UT, the 94 km diameter asteroid (1268) Libya will occult a 11.3 mag star in the constellation Virgo for observers along a path across W Africa, E USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.8 mag to 15.1 mag (the magnitude of the asteroid) for at most 8.4 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, TMO astrometry for the asteroid kindly provided by Bill Owen, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 80 * date and approx. time of event: 2008 May 20, 01:58 - 2008 May 20, 02:11 UT * magnitude of target star: 11.3 * magnitude drop [mag]: 3.8 * estimated maximum duration [s]: 8.4 * Moon: 100 % sunlit, 28° distance * Sun: 151° distance * rough path description: W Africa, E USA The occultation path -------------------- * approximate projected width [km]: 123 * 1 sigma uncertainty interval [path widths]: +/- 0.68 * 1 sigma uncertainty interval [seconds]: +/- 6.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .034 +/- .029) * 1 sigma uncertainty ellipse (major, minor, PA): ( .035", .028", 106° ) * approx speed of asteroid's shadow [km/s]: 11.1400 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6123-00585-1 by 1268 Libya on 2008 May 20 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 -100 0 0 47 0 43 2 11 50 20 143 -1 47 42 4 46 19 53 48 39 11 45 25 7 - 99 0 0 46 31 49 2 11 46 20 144 -1 47 13 11 45 50 59 48 10 17 44 56 13 - 98 0 0 46 2 41 2 11 43 21 144 -2 46 44 2 45 21 51 47 41 8 44 27 6 - 97 0 0 45 33 19 2 11 38 22 145 -3 46 14 39 44 52 30 47 11 43 43 57 46 - 96 0 0 45 3 44 2 11 34 23 146 -4 45 45 2 44 22 56 46 42 5 43 28 14 - 95 0 0 44 33 56 2 11 30 24 147 -5 45 15 13 43 53 10 46 12 14 42 58 30 - 94 0 0 44 3 58 2 11 25 24 148 -6 44 45 13 43 23 14 45 42 10 42 28 36 - 93 0 0 43 33 49 2 11 21 25 149 -7 44 15 1 42 53 7 45 11 55 41 58 33 - 92 0 0 43 3 30 2 11 16 26 149 -7 43 44 40 42 22 51 44 41 30 41 28 21 - 91 0 0 42 33 3 2 11 11 27 150 -8 43 14 10 41 52 27 44 10 56 40 58 1 - 90 0 0 42 2 29 2 11 5 28 151 -9 42 43 32 41 21 56 43 40 13 40 27 34 - 89 0 0 41 31 48 2 11 0 28 152 -10 42 12 47 40 51 19 43 9 22 39 57 2 - 88 0 0 41 1 1 2 10 54 29 153 -11 41 41 56 40 20 36 42 38 26 39 26 24 - 87 0 0 40 30 10 2 10 48 30 154 -12 41 11 1 39 49 50 42 7 24 38 55 43 - 86 0 0 39 59 15 2 10 42 31 155 -13 40 40 1 39 18 59 41 36 17 38 24 59 - 85 0 0 39 28 18 2 10 36 31 156 -14 40 8 58 38 48 7 41 5 8 37 54 13 - 84 0 0 38 57 19 2 10 30 32 156 -15 39 37 54 38 17 13 40 33 56 37 23 26 - 83 0 0 38 26 19 2 10 23 33 157 -15 39 6 49 37 46 19 40 2 42 36 52 39 - 82 0 0 37 55 20 2 10 17 34 158 -16 38 35 44 37 15 25 39 31 29 36 21 53 - 81 0 0 37 24 23 2 10 10 35 159 -17 38 4 40 36 44 34 39 0 16 35 51 9 - 80 0 0 36 53 27 2 10 3 35 160 -18 37 33 38 36 13 45 38 29 6 35 20 27 - 79 0 0 36 22 35 2 9 56 36 161 -19 37 2 40 35 42 59 37 57 58 34 49 50 - 78 0 0 35 51 48 2 9 49 37 162 -20 36 31 46 35 12 18 37 26 54 34 19 18 - 77 0 0 35 21 6 2 9 41 38 163 -21 36 0 57 34 41 43 36 55 55 33 48 51 - 76 0 0 34 50 30 2 9 34 38 164 -22 35 30 14 34 11 14 36 25 3 33 18 31 - 75 0 0 34 20 2 2 9 26 39 165 -23 34 59 38 33 40 53 35 54 17 32 48 19 - 74 0 0 33 49 42 2 9 18 40 166 -24 34 29 11 33 10 40 35 23 39 32 18 16 - 73 0 0 33 19 31 2 9 10 40 168 -25 33 58 52 32 40 36 34 53 9 31 48 22 - 72 0 0 32 49 30 2 9 2 41 169 -26 33 28 44 32 10 43 34 22 50 31 18 38 - 71 0 0 32 19 40 2 8 54 42 170 -26 32 58 46 31 41 0 33 52 41 30 49 5 - 70 0 0 31 50 2 2 8 45 42 171 -27 32 29 1 31 11 30 33 22 45 30 19 45 - 69 0 0 31 20 37 2 8 37 43 172 -28 31 59 27 30 42 12 32 53 0 29 50 37 - 68 0 0 30 51 25 2 8 28 43 173 -29 31 30 8 30 13 8 32 23 29 29 21 43 - 67 0 0 30 22 28 2 8 20 44 175 -30 31 1 2 29 44 19 31 54 12 28 53 4 - 66 0 0 29 53 46 2 8 11 44 176 -31 30 32 12 29 15 44 31 25 11 28 24 40 - 65 0 0 29 25 20 2 8 2 45 177 -32 30 3 38 28 47 26 30 56 25 27 56 32 - 64 0 0 28 57 10 2 7 53 46 178 -33 29 35 20 28 19 24 30 27 56 27 28 40 - 63 0 0 28 29 18 2 7 44 46 180 -33 29 7 20 27 51 40 29 59 44 27 1 6 - 62 0 0 28 1 44 2 7 35 46 181 -34 28 39 38 27 24 14 29 31 50 26 33 50 - 61 0 0 27 34 29 2 7 26 47 182 -35 28 12 15 26 57 7 29 4 16 26 6 53 - 60 0 0 27 7 33 2 7 17 47 184 -36 27 45 11 26 30 19 28 37 1 25 40 16 - 59 0 0 26 40 58 2 7 7 48 185 -37 27 18 27 26 3 51 28 10 6 25 13 58 - 58 0 0 26 14 43 2 6 58 48 187 -38 26 52 5 25 37 44 27 43 32 24 48 1 - 57 0 0 25 48 49 2 6 49 48 188 -38 26 26 3 25 11 58 27 17 19 24 22 25 - 56 0 0 25 23 18 2 6 39 49 190 -39 26 0 24 24 46 34 26 51 29 23 57 12 - 55 0 0 24 58 9 2 6 30 49 191 -40 25 35 7 24 21 33 26 26 1 23 32 20 - 54 0 0 24 33 23 2 6 20 49 193 -41 25 10 14 23 56 55 26 0 57 23 7 52 - 53 0 0 24 9 1 2 6 11 49 194 -42 24 45 44 23 32 40 25 36 16 22 43 46 - 52 0 0 23 45 3 2 6 1 49 195 -42 24 21 38 23 8 49 25 11 59 22 20 5 - 51 0 0 23 21 29 2 5 51 50 197 -43 23 57 57 22 45 22 24 48 8 21 56 48 - 50 0 0 22 58 20 2 5 42 50 198 -44 23 34 41 22 22 20 24 24 41 21 33 56 - 49 0 0 22 35 37 2 5 32 50 200 -44 23 11 50 21 59 44 24 1 41 21 11 29 - 48 0 0 22 13 19 2 5 23 50 202 -45 22 49 25 21 37 34 23 39 6 20 49 27 - 47 0 0 21 51 28 2 5 13 50 203 -46 22 27 27 21 15 49 23 16 58 20 27 52 - 46 0 0 21 30 4 2 5 3 50 204 -46 22 5 56 20 54 31 22 55 17 20 6 43 - 45 0 0 21 9 6 2 4 54 50 206 -47 21 44 52 20 33 40 22 34 3 19 46 0 - 44 0 0 20 48 36 2 4 44 50 207 -48 21 24 15 20 13 17 22 13 17 19 25 45 - 43 0 0 20 28 34 2 4 35 49 209 -48 21 4 6 19 53 21 21 52 59 19 5 57 - 42 0 0 20 8 59 2 4 25 49 210 -49 20 44 25 19 33 52 21 33 10 18 46 37 - 41 0 0 19 49 53 2 4 16 49 212 -49 20 25 13 19 14 52 21 13 49 18 27 45 - 40 0 0 19 31 16 2 4 6 49 213 -50 20 6 30 18 56 21 20 54 57 18 9 21 - 39 0 0 19 13 7 2 3 57 49 214 -50 19 48 16 18 38 18 20 36 34 17 51 26 - 38 0 0 18 55 28 2 3 48 48 216 -51 19 30 31 18 20 45 20 18 41 17 34 0 - 37 0 0 18 38 18 2 3 38 48 217 -51 19 13 15 18 3 40 20 1 18 17 17 2 - 36 0 0 18 21 38 2 3 29 48 218 -51 18 56 30 17 47 5 19 44 25 17 0 35 - 35 0 0 18 5 28 2 3 20 47 220 -52 18 40 14 17 31 0 19 28 2 16 44 36 - 34 0 0 17 49 48 2 3 11 47 221 -52 18 24 29 17 15 25 19 12 10 16 29 8 - 33 0 0 17 34 39 2 3 2 46 222 -52 18 9 15 17 0 20 18 56 49 16 14 9 - 32 0 0 17 20 0 2 2 53 46 223 -53 17 54 31 16 45 46 18 41 58 15 59 41 - 31 0 0 17 5 51 2 2 44 46 224 -53 17 40 18 16 31 42 18 27 39 15 45 43 - 30 0 0 16 52 14 2 2 35 45 225 -53 17 26 36 16 18 9 18 13 51 15 32 15 - 29 0 0 16 39 8 2 2 26 45 227 -53 17 13 26 16 5 7 18 0 35 15 19 19 - 28 0 0 16 26 33 2 2 18 44 228 -53 17 0 47 15 52 36 17 47 50 15 6 53 - 27 0 0 16 14 29 2 2 9 43 229 -54 16 48 40 15 40 36 17 35 37 14 54 58 - 26 0 0 16 2 57 2 2 0 43 230 -54 16 37 4 15 29 8 17 23 57 14 43 34 - 25 0 0 15 51 57 2 1 52 42 231 -54 16 26 0 15 18 11 17 12 48 14 32 42 - 24 0 0 15 41 29 2 1 44 42 231 -54 16 15 29 15 7 46 17 2 12 14 22 21 - 23 0 0 15 31 33 2 1 36 41 232 -54 16 5 30 14 57 53 16 52 8 14 12 32 - 22 0 0 15 22 9 2 1 28 40 233 -54 15 56 3 14 48 32 16 42 37 14 3 15 - 21 0 0 15 13 17 2 1 20 40 234 -53 15 47 8 14 39 43 16 33 39 13 54 29 - 20 0 0 15 4 58 2 1 12 39 235 -53 15 38 46 14 31 26 16 25 13 13 46 16 - 19 0 0 14 57 11 2 1 4 38 236 -53 15 30 57 14 23 41 16 17 21 13 38 34 - 18 0 0 14 49 56 2 0 56 38 236 -53 15 23 40 14 16 29 16 10 1 13 31 25 - 17 0 0 14 43 15 2 0 49 37 237 -53 15 16 57 14 9 49 16 3 15 13 24 48 - 16 0 0 14 37 6 2 0 42 36 238 -52 15 10 47 14 3 43 15 57 2 13 18 43 - 15 0 0 14 31 31 2 0 34 35 238 -52 15 5 9 13 58 8 15 51 22 13 13 11 - 14 0 0 14 26 28 2 0 27 35 239 -52 15 0 5 13 53 7 15 46 16 13 8 11 - 13 0 0 14 21 58 2 0 20 34 240 -51 14 55 34 13 48 39 15 41 44 13 3 45 - 12 0 0 14 18 2 2 0 13 33 240 -51 14 51 37 13 44 43 15 37 45 12 59 50 - 11 0 0 14 14 39 2 0 7 32 241 -51 14 48 13 13 41 21 15 34 20 12 56 29 - 10 0 0 14 11 49 2 0 0 32 241 -50 14 45 23 13 38 32 15 31 29 12 53 41 - 9 0 0 14 9 33 1 59 54 31 242 -50 14 43 6 13 36 16 15 29 12 12 51 26 - 8 0 0 14 7 50 1 59 48 30 242 -49 14 41 23 13 34 34 15 27 28 12 49 43 - 7 0 0 14 6 41 1 59 41 29 243 -49 14 40 14 13 33 24 15 26 19 12 48 34 - 6 0 0 14 6 6 1 59 36 28 243 -48 14 39 39 13 32 49 15 25 44 12 47 59 - 5 0 0 14 6 4 1 59 30 27 244 -48 14 39 38 13 32 47 15 25 44 12 47 56 - 4 0 0 14 6 36 1 59 24 27 244 -47 14 40 11 13 33 19 15 26 17 12 48 27 - 3 0 0 14 7 42 1 59 19 26 245 -46 14 41 17 13 34 24 15 27 25 12 49 31 - 2 0 0 14 9 22 1 59 13 25 245 -46 14 42 59 13 36 3 15 29 8 12 51 9 - 1 0 0 14 11 37 1 59 8 24 245 -45 14 45 14 13 38 16 15 31 25 12 53 20 0 0 0 14 14 25 1 59 3 23 246 -44 14 48 3 13 41 3 15 34 17 12 56 5 1 0 0 14 17 47 1 58 58 22 246 -44 14 51 27 13 44 23 15 37 43 12 59 24 2 0 0 14 21 44 1 58 54 21 247 -43 14 55 26 13 48 18 15 41 44 13 3 16 3 0 0 14 26 14 1 58 49 20 247 -42 14 59 59 13 52 47 15 46 19 13 7 43 4 0 0 14 31 19 1 58 45 19 247 -42 15 5 6 13 57 50 15 51 30 13 12 43 5 0 0 14 36 59 1 58 41 19 248 -41 15 10 48 14 3 27 15 57 15 13 18 16 6 0 0 14 43 12 1 58 37 18 248 -40 15 17 4 14 9 38 16 3 35 13 24 24 7 0 0 14 50 1 1 58 34 17 248 -39 15 23 55 14 16 23 16 10 30 13 31 6 8 0 0 14 57 23 1 58 30 16 249 -39 15 31 21 14 23 43 16 18 0 13 38 21 9 0 0 15 5 20 1 58 27 15 249 -38 15 39 21 14 31 37 16 26 5 13 46 11 10 0 0 15 13 52 1 58 24 14 249 -37 15 47 56 14 40 5 16 34 45 13 54 35 11 0 0 15 22 57 1 58 21 13 250 -36 15 57 5 14 49 7 16 43 59 14 3 32 12 0 0 15 32 38 1 58 18 12 250 -35 16 6 50 14 58 44 16 53 49 14 13 4 13 0 0 15 42 53 1 58 15 11 250 -34 16 17 9 15 8 54 17 4 14 14 23 9 14 0 0 15 53 42 1 58 13 10 250 -34 16 28 2 15 19 40 17 15 14 14 33 49 15 0 0 16 5 6 1 58 11 9 251 -33 16 39 31 15 30 59 17 26 48 14 45 3 16 0 0 16 17 4 1 58 9 8 251 -32 16 51 34 15 42 53 17 38 58 14 56 50 17 0 0 16 29 37 1 58 7 7 251 -31 17 4 11 15 55 21 17 51 42 15 9 12 18 0 0 16 42 44 1 58 6 6 252 -30 17 17 23 16 8 23 18 5 2 15 22 7 19 0 0 16 56 25 1 58 5 5 252 -29 17 31 10 16 21 59 18 18 56 15 35 36 20 0 0 17 10 41 1 58 3 4 252 -28 17 45 31 16 36 9 18 33 25 .. .. .. 21 0 0 17 25 30 1 58 3 3 252 -27 18 0 26 16 50 53 18 48 28 .. .. .. 22 0 0 17 40 54 1 58 2 2 253 -26 18 15 56 17 6 11 19 4 6 .. .. .. 23 0 0 17 56 52 1 58 2 1 253 -25 18 32 0 17 22 3 19 20 18 .. .. .. 24 0 0 18 13 23 1 58 1 0 253 -24 18 48 37 17 38 28 .. .. .. .. .. .. Uncertainty in time = +/- 7 secs [Prediction of 2008 May 8.0] Data for the target star ------------------------ * name: TYC 6123-00585-1 * constellation : Virgo * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 13 48 26.4074 DE: -15 35 55.234 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .022, .021 ) * V mag [mag]: 11.3 * B mag [mag]: 12.1 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1268) Libya approx. diameter [km]: 94 approx. diameter ["]: .042 distance from Earth [AU]: 3.06600 * orbital information: orbit source: Preston date of fit: 2008 May 07 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 916 number of rejected observations: 68 time covered by the observations: 1930 Apr 29 - 2008 Apr 25 1 sigma uncertainty ellipse (major, minor, PA): 0.028, 0.019, 115° remarks: * orbital elements for (1268) Libya : Mean anomaly = 87.22430151 deg Arg. of pericenter = 126.91498807 deg Long. of node = 351.77342510 deg Inclination = 4.42316911 deg Eccentricity = 0.10407606 Semimajor axis = 3.95963191 AU Perihelion dist = 3.54752903 AU Mag: H = 8.94, G = 0.15 Epoch of elements : MJD 54606.08700000 TDT (2008 May 20.087) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 20 1268 Libya 2h 5.3m UT 11.3 13 48 26.407-15 35 55.23TYC 6123-00585-1 12.1 15.1 94 8.4 3.066 -1.162 6.54 -62.3252 -15.600 147.81 20.03 2.0885 0.23405 0.60148 -5.85889 2.28228 0.00271 -0.00063 2000 86.4628802008 514.00000126.914988351.773425 4.4231690.10407606 3.9596319 3.5475290 9.1 5.00.15 RATE 1.2508980 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.035 0.028 106 1.68 0.029 0 54594.5020080520_0585-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 May 08, 03:39 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org