IOTA/IOTA-ES occultation update for (266) Aline / TYC 5492-00058-1 event on 2008 Apr 04, 03:06 UT Visible from W Africa Summary ------- On 2008 Apr 04 UT, the 126 km diameter asteroid (266) Aline will occult a 12.1 mag star in the constellation Sextans for observers along a path across W Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.8 mag to 13.7 mag (the magnitude of the asteroid) for at most 11.0 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: UCAC. The event at a glimpse ---------------------- * Rank: 94 * date and approx. time of event: 2008 Apr 04, 03:02 - 2008 Apr 04, 03:10 UT * magnitude of target star: 12.1 * magnitude drop [mag]: 1.8 * estimated maximum duration [s]: 11.0 * Moon: 5 % sunlit, 164° distance * Sun: 145° distance * rough path description: W Africa The occultation path -------------------- * approximate projected width [km]: 326 * 1 sigma uncertainty interval [path widths]: +/- 0.45 * 1 sigma uncertainty interval [seconds]: +/- 5.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .032 +/- .038) * 1 sigma uncertainty ellipse (major, minor, PA): ( .038", .032", 1° ) * approx speed of asteroid's shadow [km/s]: 11.4436 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5492-00058-1 by 266 Aline on 2008 Apr 4 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 - 12 19 29 60 0 0 3 10 0 2 248 -19 ... .. .. - 17 39 11 ... .. .. - 21 25 32 - 15 31 13 59 0 0 3 9 57 4 245 -21 - 9 25 41 - 19 57 19 ... .. .. - 23 17 40 - 17 56 4 58 0 0 3 9 54 6 243 -22 - 13 4 33 - 21 49 10 - 6 28 15 - 24 50 56 - 19 51 33 57 0 0 3 9 49 7 241 -24 - 15 41 5 - 23 21 45 - 10 47 28 - 26 9 24 - 21 26 10 56 0 0 3 9 45 8 240 -25 - 17 42 47 - 24 39 19 - 13 37 21 - 27 15 49 - 22 44 53 55 0 0 3 9 40 10 239 -26 - 19 21 1 - 25 44 45 - 15 45 14 - 28 12 12 - 23 50 53 54 0 0 3 9 35 11 238 -27 - 20 41 53 - 26 40 4 - 17 26 38 - 28 59 59 - 24 46 23 53 0 0 3 9 29 12 237 -28 - 21 49 9 - 27 26 46 - 18 49 8 - 29 40 20 - 25 32 59 52 0 0 3 9 23 13 237 -30 - 22 45 18 - 28 6 1 - 19 57 7 - 30 14 9 - 26 11 54 51 0 0 3 9 17 14 237 -31 - 23 32 8 - 28 38 40 - 20 53 24 - 30 42 7 - 26 44 4 50 0 0 3 9 10 14 236 -32 - 24 10 57 - 29 5 29 - 21 39 57 - 31 4 52 - 27 10 15 49 0 0 3 9 4 15 236 -33 - 24 42 46 - 29 27 2 - 22 18 11 - 31 22 51 - 27 31 1 48 0 0 3 8 57 16 236 -34 - 25 8 22 - 29 43 47 - 22 49 11 - 31 36 29 - 27 46 52 47 0 0 3 8 49 17 236 -35 - 25 28 23 - 29 56 8 - 23 13 45 - 31 46 5 - 27 58 12 46 0 0 3 8 42 17 236 -36 - 25 43 18 - 30 4 25 - 23 32 34 - 31 51 57 - 28 5 20 45 0 0 3 8 34 18 236 -37 - 25 53 32 - 30 8 54 - 23 46 6 - 31 54 20 - 28 8 35 44 0 0 3 8 26 19 236 -38 - 25 59 26 - 30 9 50 - 23 54 49 - 31 53 24 - 28 8 8 43 0 0 3 8 18 19 237 -39 - 26 1 15 - 30 7 24 - 23 59 0 - 31 49 21 - 28 4 11 42 0 0 3 8 10 20 237 -39 - 25 59 14 - 30 1 45 - 23 58 58 - 31 42 18 - 27 56 54 41 0 0 3 8 1 20 237 -40 - 25 53 32 - 29 53 1 - 23 54 53 - 31 32 23 - 27 46 23 40 0 0 3 7 52 21 238 -41 - 25 44 19 - 29 41 19 - 23 46 58 - 31 19 42 - 27 32 44 39 0 0 3 7 43 21 238 -42 - 25 31 40 - 29 26 44 - 23 35 18 - 31 4 18 - 27 16 1 38 0 0 3 7 34 21 239 -43 - 25 15 41 - 29 9 19 - 23 19 59 - 30 46 16 - 26 56 18 37 0 0 3 7 24 22 239 -44 - 24 56 25 - 28 49 7 - 23 1 4 - 30 25 37 - 26 33 34 36 0 0 3 7 15 22 240 -44 - 24 33 52 - 28 26 8 - 22 38 35 - 30 2 23 - 26 7 51 35 0 0 3 7 5 22 241 -45 - 24 8 1 - 28 0 24 - 22 12 29 - 29 36 34 - 25 39 5 34 0 0 3 6 54 22 241 -46 - 23 38 51 - 27 31 53 - 21 42 43 - 29 8 9 - 25 7 15 33 0 0 3 6 44 23 242 -47 - 23 6 17 - 27 0 32 - 21 9 12 - 28 37 6 - 24 32 14 32 0 0 3 6 33 23 243 -47 - 22 30 12 - 26 26 18 - 20 31 46 - 28 3 21 - 23 53 57 31 0 0 3 6 22 23 243 -48 - 21 50 27 - 25 49 4 - 19 50 12 - 27 26 52 - 23 12 13 30 0 0 3 6 11 23 244 -48 - 21 6 50 - 25 8 45 - 19 4 14 - 26 47 31 - 22 26 52 29 0 0 3 6 0 22 245 -49 - 20 19 4 - 24 25 11 - 18 13 30 - 26 5 11 - 21 37 36 28 0 0 3 5 48 22 246 -49 - 19 26 48 - 23 38 9 - 17 17 29 - 25 19 43 - 20 44 8 27 0 0 3 5 37 22 247 -49 - 18 29 34 - 22 47 26 - 16 15 31 - 24 30 55 - 19 46 1 26 0 0 3 5 25 22 248 -50 - 17 26 47 - 21 52 42 - 15 6 41 - 23 38 32 - 18 42 42 25 0 0 3 5 12 21 249 -50 - 16 17 36 - 20 53 34 - 13 49 40 - 22 42 15 - 17 33 28 24 0 0 3 4 59 20 250 -50 - 15 0 53 - 19 49 31 - 12 22 29 - 21 41 42 - 16 17 19 23 0 0 3 4 46 20 251 -50 - 13 34 58 - 18 39 54 - 10 42 0 - 20 36 22 - 14 52 51 22 0 0 3 4 33 19 252 -49 - 11 57 15 - 17 23 49 - 8 42 33 - 19 25 37 - 13 17 59 21 0 0 3 4 19 18 253 -49 - 10 3 25 - 16 0 1 - 6 11 45 - 18 8 37 - 11 29 22 20 0 0 3 4 5 17 254 -48 - 7 44 58 - 14 26 44 - 2 27 4 - 16 44 10 - 9 21 2 19 0 0 3 3 50 15 255 -47 - 4 39 43 - 12 41 12 ... .. .. - 15 10 37 Latitude Latitude Latitude Latitude - 9 0 0 18 51 14 3 3 47 15 255 -47 20 30 49 17 18 37 22 8 3 16 0 6 - 8 0 0 18 27 46 3 3 41 14 255 -46 20 5 52 16 56 22 21 41 22 15 38 46 - 7 0 0 18 6 35 3 3 35 13 256 -45 19 43 22 16 36 14 21 17 23 15 19 26 - 6 0 0 17 47 37 3 3 30 12 256 -45 19 23 16 16 18 10 20 56 1 15 2 4 - 5 0 0 17 30 48 3 3 25 11 257 -44 19 5 30 16 2 9 20 37 9 14 46 38 - 4 0 0 17 16 5 3 3 20 11 257 -43 18 49 59 15 48 6 20 20 44 14 33 6 - 3 0 0 17 3 28 3 3 16 10 257 -43 18 36 42 15 36 2 20 6 42 14 21 27 - 2 0 0 16 52 54 3 3 12 9 258 -42 18 25 35 15 25 54 19 55 1 14 11 39 - 1 0 0 16 44 21 3 3 8 8 258 -41 18 16 39 15 17 41 19 45 37 14 3 41 0 0 0 16 37 50 3 3 5 7 258 -40 18 9 51 15 11 23 19 38 31 13 57 34 1 0 0 16 33 18 3 3 3 6 259 -39 18 5 10 15 6 59 19 33 40 .. .. .. 2 0 0 16 30 47 3 3 0 5 259 -38 18 2 37 15 4 30 19 31 5 .. .. .. 3 0 0 16 30 16 3 2 58 4 259 -38 18 2 11 15 3 54 19 30 45 .. .. .. 4 0 0 16 31 46 3 2 57 3 260 -37 18 3 53 15 5 13 19 32 41 .. .. .. 5 0 0 16 35 17 3 2 55 2 260 -36 18 7 45 15 8 28 19 36 55 .. .. .. 6 0 0 16 40 51 3 2 55 1 260 -35 18 13 47 15 13 39 19 43 28 .. .. .. 7 0 0 16 48 30 3 2 54 0 260 -34 18 22 2 15 20 48 .. .. .. .. .. .. Uncertainty in time = +/- 5 secs [Prediction of 2008 Mar 28.0] Data for the target star ------------------------ * name: TYC 5492-00058-1 * constellation : Sextans * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 10 34 30.9175 DE: -08 59 42.453 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .026, .037 ) * V mag [mag]: 12.1 * B mag [mag]: 12.5 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (266) Aline approx. diameter [km]: 126 approx. diameter ["]: .077 distance from Earth [AU]: 2.26700 * orbital information: orbit source: Preston date of fit: 2008 Mar 27 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 791 number of rejected observations: 71 time covered by the observations: 1900 Feb 28 - 2008 Mar 26 1 sigma uncertainty ellipse (major, minor, PA): 0.019, 0.011, 108° remarks: * orbital elements for (266) Aline : Mean anomaly = 134.33022332 deg Arg. of pericenter = 151.12624277 deg Long. of node = 235.99146846 deg Inclination = 13.39037074 deg Eccentricity = 0.15756598 Semimajor axis = 2.80339975 AU Perihelion dist = 2.36167931 AU Mag: H = 8.64, G = 0.15 Epoch of elements : MJD 54560.13000000 TDT (2008 Apr 04.130) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Apr 4 266 Aline 3h 6.5m UT 12.1 10 34 30.918- 8 59 42.45TYC 5492-00058-1 12.5 13.7 126 11.0 2.267 -1.078 19.28 -80.8036 -9.000 134.13 5.81 3.1081 0.70993 0.58883 -4.12388 4.97124 0.00332 0.00017 2000 134.3029262008 4 4.00000151.126243235.991468 13.3903710.15756598 2.8033998 2.3616793 8.8 5.00.15 RATE 2.0997930 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.038 0.032 1 1.45 0.035 0 54553.5020080404_0058-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 28, 06:42 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org