IOTA/IOTA-ES occultation update for (65) Cybele / 2UCAC 24389317 event on 2008 Aug 24, 03:56 UT Visible from USA Summary ------- On 2008 Aug 24 UT, the 237 km diameter asteroid (65) Cybele will occult a 12.7 mag star in the constellation Ophiuchus for observers along a path across USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.6 mag to 12.3 mag (the magnitude of the asteroid) for at most 28.3 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: 61 * date and approx. time of event: 2008 Aug 24, 03:52 - 2008 Aug 24, 04:02 UT * magnitude of target star: 12.7 * magnitude drop [mag]: 0.6 * estimated maximum duration [s]: 28.3 * Moon: 48 % sunlit, 162° distance * Sun: 108° distance * rough path description: USA The occultation path -------------------- * approximate projected width [km]: 488 * 1 sigma uncertainty interval [path widths]: +/- 1.00 * 1 sigma uncertainty interval [seconds]: +/- 26.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .125 +/- .125) * 1 sigma uncertainty ellipse (major, minor, PA): ( .125", .125", 90° ) * approx speed of asteroid's shadow [km/s]: 8.3895 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 24389317 by 65 Cybele on 2008 Aug 24 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 -134 2 26 49 0 0 3 52 36 22 178 0 -138 43 14 -128 57 6 -147 16 10 -116 34 40 -132 23 25 48 0 0 3 52 52 23 180 -2 -137 5 55 -127 14 17 -145 38 49 -114 27 46 -130 41 10 47 0 0 3 53 9 24 181 -3 -135 26 18 -125 26 51 -144 0 25 -112 7 54 -128 55 10 46 0 0 3 53 27 25 183 -5 -133 44 1 -123 34 2 -142 20 43 -109 30 37 -127 4 51 45 0 0 3 53 46 25 185 -6 -131 58 39 -121 34 49 -140 39 26 -106 27 52 -125 9 27 44 0 0 3 54 7 26 187 -8 -130 9 42 -119 27 52 -138 56 18 -102 42 21 -123 8 2 43 0 0 3 54 30 27 190 -10 -128 16 33 -117 11 21 -137 10 57 - 97 16 18 Latitude Latitude Latitude Latitude -123 0 0 42 56 9 3 54 31 27 190 -10 40 25 26 45 42 31 35 56 30 52 36 19 -122 0 0 42 27 49 3 54 43 27 191 -11 39 58 27 45 12 23 35 31 27 51 59 6 -121 0 0 42 0 19 3 54 54 28 192 -12 39 32 14 44 43 9 35 7 5 51 23 14 -120 0 0 41 33 37 3 55 6 28 193 -13 39 6 47 44 14 48 34 43 26 50 48 40 -119 0 0 41 7 46 3 55 17 28 195 -14 38 42 7 43 47 22 34 20 31 50 15 24 -118 0 0 40 42 44 3 55 29 28 196 -15 38 18 15 43 20 51 33 58 18 49 43 23 -117 0 0 40 18 34 3 55 41 29 197 -15 37 55 10 42 55 13 33 36 50 49 12 37 -116 0 0 39 55 13 3 55 53 29 198 -16 37 32 53 42 30 31 33 16 6 48 43 5 -115 0 0 39 32 45 3 56 4 29 199 -17 37 11 25 42 6 44 32 56 7 48 14 44 -114 0 0 39 11 7 3 56 16 29 200 -18 36 50 45 41 43 52 32 36 53 47 47 35 -113 0 0 38 50 21 3 56 28 29 201 -19 36 30 54 41 21 55 32 18 25 47 21 37 -112 0 0 38 30 26 3 56 40 29 203 -20 36 11 52 41 0 53 32 0 42 46 56 48 -111 0 0 38 11 24 3 56 51 29 204 -21 35 53 40 40 40 47 31 43 45 46 33 8 -110 0 0 37 53 14 3 57 3 29 205 -22 35 36 17 40 21 36 31 27 34 46 10 37 -109 0 0 37 35 56 3 57 14 29 206 -22 35 19 45 40 3 20 31 12 9 45 49 14 -108 0 0 37 19 30 3 57 26 29 207 -23 35 4 2 39 46 0 30 57 31 45 28 58 -107 0 0 37 3 56 3 57 37 28 208 -24 34 49 8 39 29 35 30 43 40 45 9 48 -106 0 0 36 49 15 3 57 49 28 209 -25 34 35 6 39 14 6 30 30 35 44 51 45 -105 0 0 36 35 26 3 58 0 28 210 -26 34 21 53 38 59 32 30 18 17 44 34 48 -104 0 0 36 22 30 3 58 11 28 211 -27 34 9 30 38 45 53 30 6 47 44 18 56 -103 0 0 36 10 26 3 58 22 27 212 -27 33 57 58 38 33 10 29 56 3 44 4 9 -102 0 0 35 59 14 3 58 33 27 214 -28 33 47 16 38 21 22 29 46 6 43 50 26 -101 0 0 35 48 55 3 58 44 27 215 -29 33 37 24 38 10 29 29 36 56 43 37 48 -100 0 0 35 39 28 3 58 55 27 216 -30 33 28 22 38 0 31 29 28 33 43 26 13 - 99 0 0 35 30 54 3 59 5 26 217 -30 33 20 11 37 51 27 29 20 57 43 15 42 - 98 0 0 35 23 11 3 59 15 26 218 -31 33 12 49 37 43 19 29 14 8 43 6 14 - 97 0 0 35 16 21 3 59 26 25 218 -32 33 6 18 37 36 5 29 8 6 42 57 49 - 96 0 0 35 10 23 3 59 36 25 219 -32 33 0 37 37 29 46 29 2 51 42 50 26 - 95 0 0 35 5 16 3 59 45 24 220 -33 32 55 45 37 24 22 28 58 23 42 44 6 - 94 0 0 35 1 2 3 59 55 24 221 -34 32 51 44 37 19 51 28 54 42 42 38 48 - 93 0 0 34 57 39 4 0 4 23 222 -34 32 48 32 37 16 15 28 51 48 42 34 31 - 92 0 0 34 55 8 4 0 13 23 223 -35 32 46 10 37 13 33 28 49 40 42 31 16 - 91 0 0 34 53 29 4 0 22 22 224 -35 32 44 38 37 11 45 28 48 18 42 29 3 - 90 0 0 34 52 40 4 0 31 22 225 -36 32 43 55 37 10 50 28 47 44 42 27 50 - 89 0 0 34 52 43 4 0 40 21 226 -36 32 44 1 37 10 49 28 47 55 42 27 38 - 88 0 0 34 53 37 4 0 48 20 226 -37 32 44 56 37 11 42 28 48 52 42 28 27 - 87 0 0 34 55 22 4 0 56 20 227 -37 32 46 40 37 13 28 28 50 36 42 30 17 - 86 0 0 34 57 58 4 1 4 19 228 -38 32 49 13 37 16 6 28 53 5 42 33 6 - 85 0 0 35 1 24 4 1 11 18 229 -38 32 52 35 37 19 38 28 56 20 42 36 56 - 84 0 0 35 5 40 4 1 18 18 229 -39 32 56 45 37 24 3 29 0 21 42 41 46 - 83 0 0 35 10 47 4 1 25 17 230 -39 33 1 44 37 29 20 29 5 7 42 47 36 - 82 0 0 35 16 44 4 1 32 16 231 -39 33 7 31 37 35 30 29 10 38 42 54 26 - 81 0 0 35 23 31 4 1 38 16 232 -40 33 14 5 37 42 31 29 16 55 43 2 15 - 80 0 0 35 31 7 4 1 44 15 232 -40 33 21 28 37 50 25 29 23 56 43 11 4 - 79 0 0 35 39 33 4 1 50 14 233 -40 33 29 37 37 59 11 29 31 41 43 20 53 - 78 0 0 35 48 48 4 1 56 13 234 -40 33 38 35 38 8 49 29 40 11 43 31 41 - 77 0 0 35 58 52 4 2 1 13 234 -40 33 48 19 38 19 18 29 49 25 43 43 29 - 76 0 0 36 9 45 4 2 6 12 235 -41 33 58 50 38 30 38 29 59 23 43 56 16 - 75 0 0 36 21 27 4 2 10 11 236 -41 34 10 8 38 42 50 30 10 5 44 10 3 - 74 0 0 36 33 57 4 2 15 10 236 -41 34 22 12 38 55 52 .. .. .. 44 24 49 - 73 0 0 36 47 15 4 2 18 9 237 -41 34 35 2 39 9 46 .. .. .. 44 40 34 - 72 0 0 37 1 21 4 2 22 9 238 -41 34 48 39 39 24 29 .. .. .. 44 57 20 - 71 0 0 37 16 15 4 2 25 8 238 -41 35 3 0 39 40 3 .. .. .. 45 15 4 - 70 0 0 37 31 56 4 2 28 7 239 -41 35 18 7 39 56 28 .. .. .. 45 33 49 - 69 0 0 37 48 24 4 2 31 6 240 -41 35 33 59 40 13 42 .. .. .. 45 53 34 - 68 0 0 38 5 39 4 2 33 5 240 -40 35 50 36 40 31 45 .. .. .. 46 14 18 - 67 0 0 38 23 40 4 2 35 4 241 -40 36 7 57 40 50 39 .. .. .. 46 36 4 - 66 0 0 38 42 28 4 2 37 4 241 -40 36 26 2 41 10 21 .. .. .. .. .. .. - 65 0 0 39 2 2 4 2 38 3 242 -40 36 44 51 41 30 52 .. .. .. .. .. .. - 64 0 0 39 22 21 4 2 39 2 243 -40 37 4 23 41 52 12 .. .. .. .. .. .. - 63 0 0 39 43 25 4 2 40 1 243 -39 37 24 38 42 14 21 .. .. .. .. .. .. - 62 0 0 40 5 14 4 2 40 0 244 -39 37 45 35 .. .. .. .. .. .. .. .. .. Uncertainty in time = +/- 28 secs [Prediction of 2008 Aug 18.0] Data for the target star ------------------------ * name: 2UCAC 24389317 * constellation : Ophiuchus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 17 15 46.7783 DE: -19 29 12.421 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .125, .125 ) * V mag [mag]: 12.7 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (65) Cybele approx. diameter [km]: 237 approx. diameter ["]: .125 distance from Earth [AU]: 2.61400 * orbital information: orbit source: Preston date of fit: 2008 Aug 17 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1470 number of rejected observations: 128 time covered by the observations: 1903 Dec 14 - 2008 Aug 10 1 sigma uncertainty ellipse (major, minor, PA): 0.012, 0.007, 95° remarks: * orbital elements for (65) Cybele : Mean anomaly = 13.22331572 deg Arg. of pericenter = 105.50152080 deg Long. of node = 155.73536959 deg Inclination = 3.54903986 deg Eccentricity = 0.10676677 Semimajor axis = 3.43971394 AU Perihelion dist = 3.07246680 AU Mag: H = 6.71, G = 0.01 Epoch of elements : MJD 54702.16400000 TDT (2008 Aug 24.164) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Aug 24 65 Cybele 3h 56.5m UT 12.7 17 15 46.778-19 29 12.422UCAC 24389317 0.0 12.3 237 28.3 2.614 1.072 -4.94 -132.9983 -19.485 121.45 10.99 3.9424 0.27085 0.83087 4.50208 -1.46761 0.00536 -0.00053 2000 12.8889842008 822.00000105.501521155.735370 3.5490400.10676677 3.4397139 3.0724668 6.6 5.00.01 RATE 1.5449720 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.125 0.125 90 2.00 0.125 0 54696.5020080824_389317 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Aug 18, 06:16 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org