IOTA/IOTA-ES occultation update for (493) Griseldis / TYC 1211-00129-1 event on 2008 Mar 01, 03:50 UT Visible from NW USA Summary ------- On 2008 Mar 01 UT, the 46 km diameter asteroid (493) Griseldis will occult a 11.8 mag star in the constellation Pisces for observers along a path across NW USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.9 mag to 15.7 mag (the magnitude of the asteroid) for at most 1.2 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 Mar 01, 03:51 - 2008 Mar 01, 03:52 UT * midpoint of event [JD]: 2454526.65964583 * magnitude of target star: 11.8 * magnitude drop [mag]: 3.9 * estimated maximum duration [s]: 1.2 * Moon: 40 % sunlit, 130° distance * Sun: 51° distance * rough path description: NW USA The occultation path -------------------- * approximate projected width [km]: 49 * 1 sigma uncertainty interval [path widths]: +/- 1.01 * 1 sigma uncertainty interval [seconds]: +/- 1.5 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .026 +/- .022) * 1 sigma uncertainty ellipse (major, minor, PA): ( .026", .021", 71° ) * approx speed of asteroid's shadow [km/s]: 37.4384 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1211-00129-1 by 493 Griseldis on 2008 Mar 1 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 -153 0 0 48 58 14 3 51 31 49 242 0 48 45 4 49 11 25 48 18 31 49 38 7 -152 0 0 49 1 21 3 51 32 48 243 -1 48 48 12 49 14 32 48 21 40 49 41 12 -151 0 0 49 4 6 3 51 34 48 244 -2 48 50 57 49 17 16 48 24 26 49 43 56 -150 0 0 49 6 29 3 51 35 47 245 -2 48 53 20 49 19 39 48 26 50 49 46 17 -149 0 0 49 8 29 3 51 37 46 246 -3 48 55 21 49 21 38 48 28 51 49 48 16 -148 0 0 49 10 7 3 51 38 46 247 -4 48 56 59 49 23 16 48 30 30 49 49 53 -147 0 0 49 11 23 3 51 40 45 248 -4 48 58 15 49 24 32 48 31 47 49 51 9 -146 0 0 49 12 17 3 51 41 45 249 -5 48 59 9 49 25 26 48 32 41 49 52 2 -145 0 0 49 12 49 3 51 43 44 250 -6 48 59 41 49 25 57 48 33 13 49 52 33 -144 0 0 49 12 58 3 51 44 43 251 -6 48 59 51 49 26 7 48 33 23 49 52 43 -143 0 0 49 12 46 3 51 45 43 252 -7 48 59 38 49 25 54 48 33 10 49 52 31 -142 0 0 49 12 11 3 51 47 42 253 -7 48 59 3 49 25 20 48 32 35 49 51 56 -141 0 0 49 11 14 3 51 48 41 254 -8 48 58 6 49 24 23 48 31 38 49 51 0 -140 0 0 49 9 55 3 51 50 41 255 -9 48 56 47 49 23 5 48 30 18 49 49 42 -139 0 0 49 8 14 3 51 51 40 256 -9 48 55 6 49 21 24 48 28 36 49 48 2 -138 0 0 49 6 11 3 51 52 40 257 -10 48 53 2 49 19 21 48 26 32 49 46 0 -137 0 0 49 3 46 3 51 54 39 258 -11 48 50 37 49 16 56 48 24 5 49 43 36 -136 0 0 49 0 58 3 51 55 38 259 -11 48 47 48 49 14 9 48 21 16 49 40 50 -135 0 0 48 57 48 3 51 56 38 259 -12 48 44 38 49 11 0 48 18 4 49 37 42 -134 0 0 48 54 16 3 51 57 37 260 -13 48 41 5 49 7 28 48 14 30 49 34 12 -133 0 0 48 50 22 3 51 59 36 261 -13 48 37 10 49 3 35 48 10 33 49 30 20 -132 0 0 48 46 4 3 52 0 36 262 -14 48 32 52 48 59 18 48 6 13 49 26 5 -131 0 0 48 41 25 3 52 1 35 263 -15 48 28 11 48 54 39 48 1 31 49 21 28 -130 0 0 48 36 22 3 52 2 34 264 -15 48 23 8 48 49 38 47 56 26 49 16 28 -129 0 0 48 30 57 3 52 4 34 265 -16 48 17 42 48 44 14 47 50 57 49 11 6 -128 0 0 48 25 9 3 52 5 33 266 -17 48 11 53 48 38 27 47 45 6 49 5 22 -127 0 0 48 18 58 3 52 6 32 266 -17 48 5 41 48 32 17 47 38 52 48 59 14 -126 0 0 48 12 25 3 52 7 32 267 -18 47 59 5 48 25 45 47 32 15 48 52 44 -125 0 0 48 5 28 3 52 8 31 268 -19 47 52 7 48 18 49 47 25 14 48 45 51 -124 0 0 47 58 7 3 52 9 30 269 -19 47 44 46 48 11 30 47 17 49 48 38 35 -123 0 0 47 50 24 3 52 10 30 270 -20 47 37 0 48 3 48 47 10 1 48 30 55 -122 0 0 47 42 16 3 52 11 29 271 -21 47 28 52 47 55 42 47 1 50 48 22 53 -121 0 0 47 33 45 3 52 12 28 271 -22 47 20 19 47 47 13 46 53 14 48 14 26 -120 0 0 47 24 51 3 52 13 28 272 -22 47 11 23 47 38 20 46 44 15 48 5 37 -119 0 0 47 15 32 3 52 14 27 273 -23 47 2 3 47 29 3 46 34 52 47 56 23 -118 0 0 47 5 50 3 52 15 26 274 -24 46 52 19 47 19 22 46 25 4 47 46 46 -117 0 0 46 55 43 3 52 16 26 275 -24 46 42 10 47 9 17 46 14 52 47 36 44 -116 0 0 46 45 12 3 52 17 25 275 -25 46 31 37 46 58 47 46 4 15 47 26 18 -115 0 0 46 34 16 3 52 18 24 276 -26 46 20 39 46 47 53 45 53 14 47 15 28 -114 0 0 46 22 55 3 52 19 24 277 -27 46 9 17 46 36 35 45 41 47 47 4 14 -113 0 0 46 11 10 3 52 20 23 278 -27 45 57 30 46 24 52 45 29 56 46 52 34 -112 0 0 45 59 0 3 52 21 22 278 -28 45 45 17 46 12 43 45 17 40 46 40 30 -111 0 0 45 46 24 3 52 22 21 279 -29 45 32 40 46 0 10 45 4 58 46 28 1 -110 0 0 45 33 24 3 52 23 21 280 -29 45 19 37 45 47 11 44 51 51 46 15 7 -109 0 0 45 19 57 3 52 24 20 281 -30 45 6 9 45 33 47 44 38 18 46 1 47 -108 0 0 45 6 6 3 52 24 19 281 -31 44 52 15 45 19 58 44 24 20 45 48 2 -107 0 0 44 51 48 3 52 25 18 282 -32 44 37 55 45 5 42 44 9 56 45 33 51 -106 0 0 44 37 4 3 52 26 18 283 -32 44 23 9 44 51 1 43 55 5 45 19 15 -105 0 0 44 21 55 3 52 27 17 284 -33 44 7 57 44 35 53 43 39 48 45 4 12 -104 0 0 44 6 19 3 52 27 16 284 -34 43 52 19 44 20 20 43 24 5 44 48 43 -103 0 0 43 50 16 3 52 28 15 285 -35 43 36 14 44 4 20 43 7 56 44 32 48 -102 0 0 43 33 47 3 52 29 15 286 -35 43 19 43 43 47 54 42 51 20 44 16 27 -101 0 0 43 16 52 3 52 29 14 286 -36 43 2 45 43 31 0 42 34 17 43 59 38 -100 0 0 42 59 30 3 52 30 13 287 -37 42 45 20 43 13 41 42 16 47 43 42 24 - 99 0 0 42 41 40 3 52 30 12 288 -38 42 27 28 42 55 54 41 58 51 43 24 42 - 98 0 0 42 23 24 3 52 31 11 288 -39 42 9 9 42 37 40 41 40 27 43 6 33 - 97 0 0 42 4 41 3 52 31 11 289 -39 41 50 24 42 18 59 41 21 36 42 47 58 - 96 0 0 41 45 30 3 52 32 10 290 -40 41 31 11 41 59 51 41 2 18 42 28 55 - 95 0 0 41 25 53 3 52 32 9 291 -41 41 11 30 41 40 16 40 42 32 42 9 25 - 94 0 0 41 5 47 3 52 33 8 291 -42 40 51 23 41 20 14 40 22 19 41 49 28 - 93 0 0 40 45 15 3 52 33 7 292 -43 40 30 47 40 59 44 40 1 39 41 29 3 - 92 0 0 40 24 15 3 52 33 7 292 -43 40 9 45 40 38 46 39 40 32 41 8 11 - 91 0 0 40 2 48 3 52 34 6 293 -44 39 48 15 40 17 22 39 18 57 40 46 51 - 90 0 0 39 40 53 3 52 34 5 294 -45 39 26 18 39 55 29 38 56 54 40 25 4 - 89 0 0 39 18 30 3 52 34 4 294 -46 39 3 53 39 33 10 38 34 24 40 2 50 - 88 0 0 38 55 41 3 52 34 3 295 -47 38 41 1 39 10 22 38 11 27 39 40 8 - 87 0 0 38 32 24 3 52 34 2 296 -48 38 17 41 38 47 8 37 48 2 39 16 58 - 86 0 0 38 8 40 3 52 34 1 296 -49 37 53 54 38 23 26 37 24 11 38 53 22 - 85 0 0 37 44 28 3 52 34 1 297 -49 37 29 41 37 59 17 36 59 52 38 29 18 Uncertainty in time = +/- 2 secs [Prediction of 2008 Feb 18.0] Data for the target star ------------------------ * name: TYC 1211-00129-1 * constellation : Pisces * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 01 42 19.7586 DE: +21 19 44.984 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .018, .016 ) * V mag [mag]: 11.8 * B mag [mag]: 12.3 * Apparent position with proper motion RA(deg): 25.6926737129 DE(deg): 21.3715254414 * Equation of equinoxes (radians) : 0.000044537708686 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (493) Griseldis approx. diameter [km]: 46 approx. diameter ["]: .021 distance from Earth [AU]: 3.09200 * orbital information: orbit source: Preston date of fit: 2008 Feb 18 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 722 number of rejected observations: 26 time covered by the observations: 1902 Sep 07 - 2008 Jan 20 1 sigma uncertainty ellipse (major, minor, PA): 0.020, 0.014, 56° remarks: * orbital elements for (493) Griseldis : Mean anomaly = 3.68563081 deg Arg. of pericenter = 47.23056164 deg Long. of node = 357.50892693 deg Inclination = 15.14683357 deg Eccentricity = 0.17069933 Semimajor axis = 3.12230964 AU Perihelion dist = 2.58933347 AU Mag: H = 10.83, G = 0.15 Epoch of elements : MJD 54526.16000000 TDT (2008 Mar 01.160) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Mar 1 493 Griseldis 3h 49.9m UT 11.8 1 42 19.759 21 19 44.98TYC 1211-00129-1 12.3 15.7 46 1.2 3.092 3.997 22.21 168.7816 21.323 125.62 -7.46 3.8315 -0.12027 0.30087 19.63529 7.80944 0.00396 0.00223 2000 2.5851802008 224.00000 47.230562357.508927 15.1468340.17069933 3.1223096 2.589333510.3 5.00.15 RATE 1.7864470 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.026 0.021 71 2.01 0.021 0 54514.5020080301_0129-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Feb 18, 17:25 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org