IOTA/IOTA-ES occultation update for (95) Arethusa / 2UCAC 37144468 event on 2008 May 01, 18:46 UT Visible from SE Europe, SW Asia Summary ------- On 2008 May 01 UT, the 136 km diameter asteroid (95) Arethusa will occult a 12.2 mag star in the constellation Orion for observers along a path across SE Europe, SW Asia. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.7 mag to 13.6 mag (the magnitude of the asteroid) for at most 3.8 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: 63 * date and approx. time of event: 2008 May 01, 18:48 - 2008 May 01, 18:48 UT * magnitude of target star: 12.2 * magnitude drop [mag]: 1.7 * estimated maximum duration [s]: 3.8 * Moon: 19 % sunlit, 103° distance * Sun: 52° distance * rough path description: SE Europe, SW Asia The occultation path -------------------- * approximate projected width [km]: 167 * 1 sigma uncertainty interval [path widths]: +/- 0.98 * 1 sigma uncertainty interval [seconds]: +/- 3.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .055 +/- .055) * 1 sigma uncertainty ellipse (major, minor, PA): ( .055", .055", 91° ) * approx speed of asteroid's shadow [km/s]: 35.5939 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 37144468 by 95 Arethusa on 2008 May 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 4 0 0 44 55 40 18 48 11 37 254 -1 44 8 40 45 43 10 42 37 49 47 17 45 5 0 0 44 42 56 18 48 13 36 255 -1 43 55 53 45 30 29 42 24 57 47 5 9 6 0 0 44 30 1 18 48 15 36 256 -2 43 42 54 45 17 36 42 11 54 46 52 22 7 0 0 44 16 54 18 48 17 35 257 -3 43 29 45 45 4 32 41 58 40 46 39 23 8 0 0 44 3 37 18 48 18 34 258 -4 43 16 25 44 51 17 41 45 16 46 26 14 9 0 0 43 50 9 18 48 20 34 259 -4 43 2 55 44 37 52 41 31 40 46 12 54 10 0 0 43 36 30 18 48 22 33 260 -5 42 49 14 44 24 16 41 17 55 45 59 23 11 0 0 43 22 41 18 48 23 32 260 -6 42 35 23 44 10 29 41 3 59 45 45 41 12 0 0 43 8 42 18 48 25 32 261 -7 42 21 21 43 56 32 40 49 53 45 31 49 13 0 0 42 54 33 18 48 26 31 262 -7 42 7 10 43 42 25 40 35 38 45 17 47 14 0 0 42 40 14 18 48 28 30 263 -8 41 52 49 43 28 9 40 21 13 45 3 35 15 0 0 42 25 46 18 48 29 30 264 -9 41 38 18 43 13 43 40 6 39 44 49 13 16 0 0 42 11 8 18 48 31 29 265 -10 41 23 39 42 59 7 39 51 55 44 34 42 17 0 0 41 56 21 18 48 32 28 266 -10 41 8 50 42 44 22 39 37 3 44 20 1 18 0 0 41 41 26 18 48 34 27 266 -11 40 53 53 42 29 28 39 22 2 44 5 11 19 0 0 41 26 21 18 48 35 27 267 -12 40 38 47 42 14 26 39 6 53 43 50 13 20 0 0 41 11 9 18 48 36 26 268 -13 40 23 32 41 59 15 38 51 36 43 35 5 21 0 0 40 55 48 18 48 38 25 269 -14 40 8 10 41 43 56 38 36 10 43 19 49 22 0 0 40 40 20 18 48 39 24 270 -14 39 52 40 41 28 29 38 20 38 43 4 25 23 0 0 40 24 43 18 48 40 24 270 -15 39 37 3 41 12 54 38 4 58 42 48 54 24 0 0 40 9 0 18 48 42 23 271 -16 39 21 18 40 57 12 37 49 11 42 33 14 25 0 0 39 53 10 18 48 43 22 272 -17 39 5 27 40 41 23 37 33 17 42 17 27 26 0 0 39 37 13 18 48 44 21 273 -17 38 49 28 40 25 27 37 17 17 42 1 34 27 0 0 39 21 9 18 48 45 21 273 -18 38 33 24 40 9 24 37 1 11 41 45 33 28 0 0 39 5 0 18 48 46 20 274 -19 38 17 14 39 53 16 36 44 59 41 29 26 29 0 0 38 48 44 18 48 47 19 275 -20 38 0 58 39 37 1 36 28 41 41 13 13 30 0 0 38 32 24 18 48 48 18 275 -21 37 44 36 39 20 41 36 12 19 40 56 55 31 0 0 38 15 58 18 48 49 17 276 -21 37 28 10 39 4 16 35 55 51 40 40 30 32 0 0 37 59 27 18 48 50 16 277 -22 37 11 39 38 47 46 35 39 20 40 24 1 33 0 0 37 42 52 18 48 51 16 278 -23 36 55 4 38 31 11 35 22 44 40 7 27 34 0 0 37 26 13 18 48 52 15 278 -24 36 38 24 38 14 32 35 6 4 39 50 49 35 0 0 37 9 30 18 48 53 14 279 -24 36 21 41 37 57 49 34 49 21 39 34 6 36 0 0 36 52 44 18 48 53 13 279 -25 36 4 55 37 41 3 34 32 35 39 17 20 37 0 0 36 35 55 18 48 54 12 280 -26 35 48 6 37 24 14 34 15 46 39 0 30 38 0 0 36 19 3 18 48 55 11 281 -27 35 31 15 37 7 22 33 58 55 38 43 38 39 0 0 36 2 9 18 48 56 11 281 -27 35 14 21 36 50 27 33 42 2 38 26 43 40 0 0 35 45 13 18 48 56 10 282 -28 34 57 26 36 33 31 33 25 8 38 9 45 41 0 0 35 28 16 18 48 57 9 283 -29 34 40 29 36 16 33 33 8 12 37 52 46 42 0 0 35 11 17 18 48 57 8 283 -30 34 23 31 35 59 34 32 51 15 37 35 45 43 0 0 34 54 18 18 48 58 7 284 -30 34 6 33 35 42 34 32 34 18 37 18 44 44 0 0 34 37 19 18 48 58 6 284 -31 33 49 34 35 25 33 .. .. .. 37 1 41 45 0 0 34 20 19 18 48 58 5 285 -32 33 32 35 35 8 33 .. .. .. 36 44 39 46 0 0 34 3 20 18 48 59 5 285 -33 33 15 38 34 51 33 .. .. .. 36 27 36 47 0 0 33 46 22 18 48 59 4 286 -33 32 58 41 34 34 34 .. .. .. 36 10 34 48 0 0 33 29 25 18 48 59 3 287 -34 32 41 45 34 17 35 .. .. .. 35 53 34 49 0 0 33 12 30 18 48 59 2 287 -35 32 24 51 34 0 39 .. .. .. 35 36 34 50 0 0 32 55 37 18 48 59 1 288 -35 32 8 0 33 43 44 .. .. .. 35 19 36 51 0 0 32 38 46 18 48 59 0 288 -36 .. .. .. 33 26 52 .. .. .. 35 2 41 Uncertainty in time = +/- 4 secs [Prediction of 2008 Apr 23.0] Data for the target star ------------------------ * name: 2UCAC 37144468 * constellation : Orion * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 06 13 31.0736 DE: +15 21 00.643 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .054, .054 ) * V mag [mag]: 12.2 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (95) Arethusa approx. diameter [km]: 136 approx. diameter ["]: .056 distance from Earth [AU]: 3.37500 * orbital information: orbit source: Preston date of fit: 2008 Apr 22 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 715 number of rejected observations: 101 time covered by the observations: 1904 Sep 07 - 2008 Apr 16 1 sigma uncertainty ellipse (major, minor, PA): 0.012, 0.008, 102° remarks: * orbital elements for (95) Arethusa : Mean anomaly = 56.45256611 deg Arg. of pericenter = 154.96733999 deg Long. of node = 243.14634139 deg Inclination = 12.99747502 deg Eccentricity = 0.14931003 Semimajor axis = 3.06868634 AU Perihelion dist = 2.61050070 AU Mag: H = 7.94, G = 0.15 Epoch of elements : MJD 54587.78200000 TDT (2008 May 01.782) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 1 95 Arethusa 18h 46.6m UT 12.2 6 13 31.074 15 21 0.642UCAC 37144468 0.0 13.6 136 3.8 3.375 3.617 -1.64 -48.3265 15.351 -102.38 15.36 18.7760 0.01744 0.58073 20.08037 -0.62883 0.00447 -0.00060 2000 55.0257552008 424.00000154.967340243.146341 12.9974750.14931003 3.0686863 2.6105007 7.8 5.00.15 RATE 1.8334760 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.055 0.055 91 1.98 0.054 0 54579.5020080501_144468 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 23, 03:43 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org