IOTA/IOTA-ES occultation update for (155) Scylla / HIP 22298 event on 2008 Oct 15, 02:41 UT Visible from Africa Summary ------- On 2008 Oct 15 UT, the 40 km diameter asteroid (155) Scylla will occult a 9.0 mag star in the constellation Taurus for observers along a path across Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 5.6 mag to 14.6 mag (the magnitude of the asteroid) for at most 6.4 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: 52 * date and approx. time of event: 2008 Oct 15, 02:24 - 2008 Oct 15, 02:51 UT * magnitude of target star: 9.0 * magnitude drop [mag]: 5.6 * estimated maximum duration [s]: 6.4 * Moon: 100 % sunlit, 48° distance * Sun: 128° distance * rough path description: Africa The occultation path -------------------- * approximate projected width [km]: 42 * 1 sigma uncertainty interval [path widths]: +/- 1.22 * 1 sigma uncertainty interval [seconds]: +/- 7.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .061 +/- .035) * 1 sigma uncertainty ellipse (major, minor, PA): ( .062", .032", 75° ) * approx speed of asteroid's shadow [km/s]: 6.2162 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of HIP 22298 by 155 Scylla on 2008 Oct 15 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 - 1 33 23 -63 0 0 2 24 36 1 12 -13 - 1 8 14 - 1 58 32 - 0 6 55 - 2 59 59 - 1 5 9 -62 0 0 2 24 37 2 12 -13 - 0 40 51 - 1 29 27 0 18 24 - 2 28 49 - 0 38 7 -61 0 0 2 24 37 3 11 -14 - 0 14 37 - 1 1 39 0 42 44 - 1 59 5 - 0 12 11 -60 0 0 2 24 38 4 11 -15 0 10 36 - 0 34 59 1 6 11 - 1 30 38 0 12 46 -59 0 0 2 24 40 5 11 -15 0 34 52 - 0 9 21 1 28 48 - 1 3 20 0 36 50 -58 0 0 2 24 41 6 10 -16 0 58 18 0 15 21 1 50 42 - 0 37 6 1 0 5 -57 0 0 2 24 43 7 10 -16 1 20 58 0 39 11 2 11 56 - 0 11 48 1 22 36 -56 0 0 2 24 46 8 10 -17 1 42 56 1 2 15 2 32 33 0 12 37 1 44 27 -55 0 0 2 24 49 9 9 -18 2 4 16 1 24 37 2 52 38 0 36 15 2 5 40 -54 0 0 2 24 52 10 9 -18 2 25 1 1 46 20 3 12 12 0 59 9 2 26 21 -53 0 0 2 24 55 11 9 -19 2 45 13 2 7 28 3 31 18 1 21 23 2 46 30 -52 0 0 2 24 59 12 8 -19 3 4 57 2 28 3 3 49 59 1 43 1 3 6 10 -51 0 0 2 25 3 13 8 -20 3 24 13 2 48 7 4 8 16 2 4 5 3 25 25 -50 0 0 2 25 7 14 8 -20 3 43 5 3 7 45 4 26 12 2 24 39 3 44 15 -49 0 0 2 25 12 15 8 -21 4 1 33 3 26 57 4 43 48 2 44 43 4 2 43 -48 0 0 2 25 17 16 7 -22 4 19 41 3 45 45 5 1 6 3 4 22 4 20 51 -47 0 0 2 25 22 17 7 -22 4 37 30 4 4 12 5 18 8 3 23 36 4 38 39 -46 0 0 2 25 28 18 7 -23 4 55 0 4 22 19 5 34 54 3 42 27 4 56 11 -45 0 0 2 25 34 19 7 -23 5 12 14 4 40 8 5 51 26 4 0 58 5 13 26 -44 0 0 2 25 41 20 6 -23 5 29 13 4 57 40 6 7 45 4 19 10 5 30 27 -43 0 0 2 25 47 21 6 -24 5 45 59 5 14 56 6 23 53 4 37 4 5 47 15 -42 0 0 2 25 54 22 6 -24 6 2 31 5 31 58 6 39 50 4 54 42 6 3 50 -41 0 0 2 26 2 23 5 -25 6 18 53 5 48 47 6 55 37 5 12 5 6 20 13 -40 0 0 2 26 9 24 5 -25 6 35 3 6 5 24 7 11 15 5 29 15 6 36 27 -39 0 0 2 26 17 25 5 -26 6 51 4 6 21 50 7 26 46 5 46 12 6 52 31 -38 0 0 2 26 26 26 5 -26 7 6 56 6 38 6 7 42 9 6 2 57 7 8 27 -37 0 0 2 26 34 27 4 -26 7 22 41 6 54 14 7 57 26 6 19 32 7 24 16 -36 0 0 2 26 43 28 4 -27 7 38 19 7 10 13 8 12 38 6 35 57 7 39 57 -35 0 0 2 26 52 29 4 -27 7 53 50 7 26 5 8 27 44 6 52 14 7 55 33 -34 0 0 2 27 2 30 4 -28 8 9 17 7 41 50 8 42 47 7 8 23 8 11 4 -33 0 0 2 27 12 31 3 -28 8 24 38 7 57 30 8 57 46 7 24 26 8 26 31 -32 0 0 2 27 22 32 3 -28 8 39 56 8 13 5 9 12 43 7 40 22 8 41 53 -31 0 0 2 27 32 33 3 -29 8 55 11 8 28 37 9 27 38 7 56 14 8 57 14 -30 0 0 2 27 43 34 2 -29 9 10 23 8 44 4 9 42 31 8 12 1 9 12 31 -29 0 0 2 27 54 35 2 -29 9 25 34 8 59 30 9 57 23 8 27 44 9 27 48 -28 0 0 2 28 5 36 2 -29 9 40 43 9 14 53 10 12 16 8 43 24 9 43 3 -27 0 0 2 28 17 37 2 -30 9 55 52 9 30 15 10 27 9 8 59 3 9 58 19 -26 0 0 2 28 28 38 1 -30 10 11 1 9 45 37 10 42 3 9 14 40 10 13 35 -25 0 0 2 28 40 39 1 -30 10 26 11 10 0 59 10 56 59 9 30 16 10 28 52 -24 0 0 2 28 53 40 1 -30 10 41 23 10 16 21 11 11 57 9 45 52 10 44 11 -23 0 0 2 29 5 41 0 -31 10 56 37 10 31 46 11 26 58 10 1 29 10 59 33 -22 0 0 2 29 18 42 360 -31 11 11 54 10 47 12 11 42 3 10 17 7 11 14 57 -21 0 0 2 29 32 43 359 -31 11 27 14 11 2 41 11 57 13 10 32 47 11 30 26 -20 0 0 2 29 45 44 359 -31 11 42 38 11 18 14 12 12 27 10 48 30 11 45 59 -19 0 0 2 29 59 45 359 -31 11 58 7 11 33 51 12 27 46 11 4 16 12 1 37 -18 0 0 2 30 13 46 358 -31 12 13 42 11 49 32 12 43 12 11 20 7 12 17 21 -17 0 0 2 30 27 47 358 -31 12 29 22 12 5 20 12 58 45 11 36 2 12 33 11 -16 0 0 2 30 41 48 357 -31 12 45 10 12 21 13 13 14 25 11 52 3 12 49 9 -15 0 0 2 30 56 49 357 -31 13 1 5 12 37 13 13 30 13 12 8 10 13 5 14 -14 0 0 2 31 11 50 356 -31 13 17 8 12 53 21 13 46 11 12 24 24 13 21 29 -13 0 0 2 31 26 51 356 -31 13 33 20 13 9 38 14 2 18 12 40 46 13 37 52 -12 0 0 2 31 41 52 355 -31 13 49 42 13 26 4 14 18 35 12 57 16 13 54 26 -11 0 0 2 31 57 53 354 -31 14 6 14 13 42 39 14 35 3 13 13 56 14 11 11 -10 0 0 2 32 13 54 354 -31 14 22 57 13 59 25 14 51 43 13 30 45 14 28 8 - 9 0 0 2 32 29 55 353 -31 14 39 53 14 16 23 15 8 36 13 47 46 14 45 17 - 8 0 0 2 32 45 56 352 -31 14 57 1 14 33 33 15 25 43 14 4 58 15 2 39 - 7 0 0 2 33 1 57 352 -31 15 14 23 14 50 56 15 43 3 14 22 22 15 20 16 - 6 0 0 2 33 18 58 351 -31 15 32 0 15 8 33 16 0 40 14 40 0 15 38 8 - 5 0 0 2 33 35 59 350 -31 15 49 52 15 26 25 16 18 32 14 57 53 15 56 17 - 4 0 0 2 33 52 60 349 -31 16 8 1 15 44 33 16 36 41 15 16 0 16 14 42 - 3 0 0 2 34 9 60 348 -31 16 26 27 16 2 58 16 55 9 15 34 24 16 33 26 - 2 0 0 2 34 27 61 347 -31 16 45 11 16 21 41 17 13 55 15 53 5 16 52 29 - 1 0 0 2 34 44 62 346 -30 17 4 15 16 40 43 17 33 2 16 12 5 17 11 52 0 0 0 2 35 2 63 344 -30 17 23 40 17 0 5 17 52 30 16 31 23 17 31 37 1 0 0 2 35 20 64 343 -30 17 43 26 17 19 48 18 12 21 16 51 3 17 51 45 2 0 0 2 35 38 65 342 -30 18 3 36 17 39 54 18 32 35 17 11 4 18 12 16 3 0 0 2 35 57 66 340 -29 18 24 10 18 0 23 18 53 15 17 31 28 18 33 13 4 0 0 2 36 15 66 338 -29 18 45 9 18 21 18 19 14 21 17 52 16 18 54 37 5 0 0 2 36 34 67 337 -29 19 6 36 18 42 38 19 35 54 18 13 30 19 16 28 6 0 0 2 36 53 68 335 -28 19 28 31 19 4 27 19 57 57 18 35 10 19 38 50 7 0 0 2 37 12 69 333 -28 19 50 55 19 26 45 20 20 31 18 57 20 20 1 42 8 0 0 2 37 31 69 330 -28 20 13 52 19 49 34 20 43 37 19 19 59 20 25 8 9 0 0 2 37 50 70 328 -27 20 37 22 20 12 55 21 7 18 19 43 11 20 49 9 10 0 0 2 38 9 70 326 -27 21 1 27 20 36 51 21 31 34 20 6 56 21 13 46 11 0 0 2 38 29 71 323 -27 21 26 10 21 1 23 21 56 29 20 31 16 21 39 2 12 0 0 2 38 49 71 320 -26 21 51 31 21 26 34 22 22 4 20 56 14 22 4 59 13 0 0 2 39 8 72 317 -26 22 17 34 21 52 25 22 48 21 21 21 51 22 31 39 14 0 0 2 39 28 72 314 -25 22 44 20 22 18 59 23 15 23 21 48 10 22 59 5 15 0 0 2 39 48 72 311 -25 23 11 53 22 46 18 23 43 13 22 15 12 23 27 19 16 0 0 2 40 9 73 307 -24 23 40 14 23 14 25 24 11 52 22 43 2 23 56 24 17 0 0 2 40 29 73 304 -24 24 9 27 23 43 22 24 41 24 23 11 41 24 26 23 18 0 0 2 40 49 73 300 -23 24 39 34 24 13 13 25 11 52 23 41 11 24 57 19 19 0 0 2 41 10 73 297 -23 25 10 40 24 44 0 25 43 20 24 11 37 Latitude Latitude Latitude Latitude 25 0 0 19 5 7 2 41 12 73 297 -23 18 39 38 19 30 26 17 36 51 20 31 37 26 0 0 20 55 55 2 41 50 72 290 -22 20 31 24 21 20 17 19 31 1 22 19 12 27 0 0 22 40 11 2 42 26 72 284 -21 22 16 34 23 3 41 21 18 25 24 0 31 28 0 0 24 18 24 2 43 1 71 279 -20 23 55 36 24 41 5 22 59 30 25 35 59 29 0 0 25 50 59 2 43 33 70 275 -19 25 28 57 26 12 56 24 34 44 27 6 2 30 0 0 27 18 20 2 44 5 69 271 -18 26 57 0 27 39 35 26 4 33 28 31 2 31 0 0 28 40 49 2 44 34 68 268 -17 28 20 8 29 1 25 27 29 18 29 51 20 32 0 0 29 58 47 2 45 2 67 266 -16 29 38 42 30 18 47 28 49 22 31 7 15 33 0 0 31 12 30 2 45 29 66 264 -15 30 52 59 31 31 57 30 5 3 32 19 6 34 0 0 32 22 18 2 45 55 65 262 -14 32 3 18 32 41 13 31 16 40 33 27 8 35 0 0 33 28 24 2 46 19 64 261 -13 33 9 54 33 46 51 32 24 28 34 31 36 36 0 0 34 31 4 2 46 42 63 260 -12 34 13 1 34 49 4 33 28 43 35 32 44 37 0 0 35 30 31 2 47 4 62 259 -11 35 12 53 35 48 5 34 29 39 36 30 44 38 0 0 36 26 56 2 47 26 61 258 -10 36 9 43 36 44 7 35 27 28 37 25 49 39 0 0 37 20 32 2 47 46 60 257 -10 37 3 41 37 37 20 36 22 21 38 18 9 40 0 0 38 11 27 2 48 5 59 257 -9 37 54 57 38 27 54 37 14 30 39 7 52 41 0 0 38 59 51 2 48 24 58 257 -8 38 43 41 39 15 59 38 4 3 39 55 10 42 0 0 39 45 53 2 48 42 57 256 -7 39 30 2 40 1 42 38 51 10 40 40 9 43 0 0 40 29 41 2 48 59 56 256 -6 40 14 7 40 45 13 39 35 58 41 22 58 44 0 0 41 11 22 2 49 15 55 256 -6 40 56 4 41 26 37 40 18 37 42 3 43 45 0 0 41 51 3 2 49 31 54 256 -5 41 36 1 42 6 3 40 59 11 42 42 31 46 0 0 42 28 49 2 49 46 53 257 -4 42 14 2 42 43 35 41 37 49 43 19 27 47 0 0 43 4 48 2 50 1 52 257 -4 42 50 14 43 19 19 42 14 36 43 54 39 48 0 0 43 39 3 2 50 15 51 257 -3 43 24 43 43 53 22 42 49 37 44 28 10 49 0 0 44 11 41 2 50 29 50 257 -2 43 57 33 44 25 47 43 22 57 45 0 6 50 0 0 44 42 45 2 50 42 50 258 -2 44 28 49 44 56 40 43 54 42 45 30 30 51 0 0 45 12 20 2 50 55 49 258 -1 44 58 35 45 26 4 44 24 56 45 59 27 52 0 0 45 40 30 2 51 7 48 258 0 45 26 56 45 54 4 44 53 42 46 27 2 Uncertainty in time = +/- 9 secs [Prediction of 2008 Oct 1.0] Data for the target star ------------------------ * name: HIP 22298 * constellation : Taurus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 04 48 06.3971 DE: +25 48 25.615 * position source: mpos:HIP pm:HIP plx:HIP * standard error: RA,DE ["]: ( .024, .017 ) * V mag [mag]: 9.0 * B mag [mag]: 9.5 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (155) Scylla approx. diameter [km]: 40 approx. diameter ["]: .042 distance from Earth [AU]: 1.30700 * orbital information: orbit source: Preston date of fit: 2008 Sep 30 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 611 number of rejected observations: 26 time covered by the observations: 1907 Nov 02 - 2008 Sep 17 1 sigma uncertainty ellipse (major, minor, PA): 0.058, 0.027, 72° remarks: * orbital elements for (155) Scylla : Mean anomaly = 340.28860052 deg Arg. of pericenter = 46.04492875 deg Long. of node = 41.04514152 deg Inclination = 11.39046631 deg Eccentricity = 0.27690707 Semimajor axis = 2.75673488 AU Perihelion dist = 1.99337550 AU Mag: H = 11.05, G = 0.15 Epoch of elements : MJD 54754.11200000 TDT (2008 Oct 15.112) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Oct 15 155 Scylla 2h 40.9m UT 9.0 4 48 6.397 25 48 25.62HIP 22298 9.5 14.6 40 6.4 1.307 0.692 21.67 7.7946 25.801 136.22 -8.62 2.6816 0.27165 -0.11710 1.39288 3.22024 -0.00415 -0.00071 2000 339.40315020081011.00000 46.044929 41.045142 11.3904660.27690707 2.7567349 1.993375511.4 5.00.15 RATE 2.1533350 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.062 0.032 75 2.22 0.052 0 54740.5020081015__22298 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Oct 01, 04:56 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org