IOTA/IOTA-ES occultation update for (0) 2001 UP18 / TYC 0621-00849-1 event on 2009 Dec 04, 18:46 UT Visible from Summary ------- On 2009 Dec 04 UT, the 238 km diameter asteroid (0) 2001 UP18 will occult a 10.8 mag star in the constellation Pisces for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 12.1 mag to 22.9 mag (the magnitude of the asteroid) for at most 14.5 seconds. This update is based on historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 0 * date and approx. time of event: 2009 Dec 04, 18:46 - 2009 Dec 04, 18:47 UT * magnitude of target star: 10.8 * magnitude drop [mag]: 12.1 * estimated maximum duration [s]: 14.5 * Moon: 91 % sunlit, 81° distance * Sun: 133° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 1247 * 1 sigma uncertainty interval [path widths]: +/- 240.47 * 1 sigma uncertainty interval [seconds]: +/- 11813.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 5.077 +/- 2.556) * 1 sigma uncertainty ellipse (major, minor, PA): ( 5.434", 1.667", 68° ) * approx speed of asteroid's shadow [km/s]: 16.4318 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 0621-00849-1 by 0 2001 UP18 on 2009 Dec 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 68 45 30 -67 0 0 18 47 42 9 320 -1 55 3 24 ... .. .. ... .. .. ... .. .. 69 51 44 -66 0 0 18 47 35 9 319 -2 56 17 0 ... .. .. ... .. .. ... .. .. 71 11 45 -65 0 0 18 47 28 10 317 -3 57 37 40 ... .. .. ... .. .. ... .. .. 72 46 36 -64 0 0 18 47 20 10 316 -4 59 5 33 ... .. .. ... .. .. ... .. .. 74 38 18 -63 0 0 18 47 11 10 314 -5 60 41 1 ... .. .. ... .. .. ... .. .. 76 50 34 -62 0 0 18 47 2 10 312 -6 62 24 40 ... .. .. ... .. .. ... .. .. Latitude Latitude Latitude Latitude 77 0 0 -61 56 6 18 47 1 10 312 -6 -56 4 47 .. .. .. .. .. .. .. .. .. 78 0 0 -61 32 25 18 46 57 10 311 -6 -55 48 34 .. .. .. .. .. .. .. .. .. 79 0 0 -61 10 30 18 46 53 10 310 -7 -55 33 16 .. .. .. .. .. .. .. .. .. 80 0 0 -60 50 14 18 46 49 10 309 -7 -55 18 54 .. .. .. .. .. .. .. .. .. 81 0 0 -60 31 30 18 46 46 10 308 -7 -55 5 26 .. .. .. .. .. .. .. .. .. 82 0 0 -60 14 15 18 46 42 9 307 -7 -54 52 53 .. .. .. .. .. .. .. .. .. 83 0 0 -59 58 24 18 46 39 9 306 -8 -54 41 13 .. .. .. .. .. .. .. .. .. 84 0 0 -59 43 54 18 46 35 9 305 -8 -54 30 27 .. .. .. .. .. .. .. .. .. 85 0 0 -59 30 43 18 46 32 9 304 -8 -54 20 34 .. .. .. .. .. .. .. .. .. 86 0 0 -59 18 48 18 46 29 8 303 -8 -54 11 35 .. .. .. .. .. .. .. .. .. 87 0 0 -59 8 7 18 46 26 8 302 -8 -54 3 28 .. .. .. .. .. .. .. .. .. 88 0 0 -58 58 39 18 46 23 8 301 -8 -53 56 13 .. .. .. .. .. .. .. .. .. 89 0 0 -58 50 23 18 46 21 7 301 -8 -53 49 51 .. .. .. .. .. .. .. .. .. 90 0 0 -58 43 18 18 46 18 7 300 -8 -53 44 21 .. .. .. .. .. .. .. .. .. 91 0 0 -58 37 22 18 46 16 6 299 -8 -53 39 43 .. .. .. .. .. .. .. .. .. 92 0 0 -58 32 35 18 46 14 6 298 -8 -53 35 58 .. .. .. .. .. .. .. .. .. 93 0 0 -58 28 57 18 46 12 6 297 -8 -53 33 4 .. .. .. .. .. .. .. .. .. 94 0 0 -58 26 27 18 46 10 5 296 -8 -53 31 3 .. .. .. .. .. .. .. .. .. 95 0 0 -58 25 5 18 46 8 5 295 -8 -53 29 54 .. .. .. .. .. .. .. .. .. 96 0 0 -58 24 51 18 46 7 4 294 -8 -53 29 37 .. .. .. .. .. .. .. .. .. 97 0 0 -58 25 46 18 46 5 4 294 -8 -53 30 12 .. .. .. .. .. .. .. .. .. 98 0 0 -58 27 48 18 46 4 3 293 -7 -53 31 39 .. .. .. .. .. .. .. .. .. 99 0 0 -58 31 0 18 46 3 3 292 -7 -53 34 0 .. .. .. .. .. .. .. .. .. 100 0 0 -58 35 21 18 46 2 2 291 -7 -53 37 12 .. .. .. .. .. .. .. .. .. 101 0 0 -58 40 52 18 46 2 2 290 -7 -53 41 18 .. .. .. .. .. .. .. .. .. 102 0 0 -58 47 34 18 46 1 1 289 -6 -53 46 17 .. .. .. .. .. .. .. .. .. 103 0 0 -58 55 28 18 46 1 1 288 -6 -53 52 9 .. .. .. .. .. .. .. .. .. 104 0 0 -59 4 35 18 46 1 0 288 -6 -53 58 55 .. .. .. .. .. .. .. .. .. Uncertainty in time = +/- 11982 secs [Prediction of 2008 Mar 20.0] Data for the target star ------------------------ * name: TYC 0621-00849-1 * constellation : Pisces * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 01 37 21.6774 DE: +08 52 55.642 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .030, .022 ) * V mag [mag]: 10.8 * B mag [mag]: 11.3 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (0) 2001 UP18 approx. diameter [km]: 238 approx. diameter ["]: .007 distance from Earth [AU]: 49.95400 * orbital information: orbit source: Preston date of fit: 2008 Mar 20 source of used astrometry: MPC (via Astdys) number of used observations: 13 number of rejected observations: 0 time covered by the observations: 2001 Oct 19 - 2005 Sep 29 1 sigma uncertainty ellipse (major, minor, PA): 5.434, 1.667, 68° remarks: * orbital elements for (0) 2001 UP18 : Mean anomaly = 134.05854656 deg Arg. of pericenter = 141.46877964 deg Long. of node = 105.20454437 deg Inclination = 1.17183875 deg Eccentricity = 0.07618295 Semimajor axis = 47.95997489 AU Perihelion dist = 44.30624253 AU Mag: H = 5.72, G = 0.15 Epoch of elements : MJD 55169.78200000 TDT (2009 Dec 04.782) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Dec 4 0 2001 UP18 18h 47.2m UT 10.8 1 37 21.677 8 52 55.64TYC 0621-00849-1 11.3 22.9 238 14.5 49.954 -0.104 -0.55 28.8337 8.882 -104.19 -22.33 18.7861 0.32913 -0.92479 -8.73547 -3.11589 0.00415 0.00171 2000 134.02951920091125.00000141.468780105.204544 1.1718390.0761829547.959974944.3062425 5.7 5.00.15 RATE 0.0296750 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 5.434 1.667 68241.47 1.580 0 54545.5020091204_0849-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 20, 17:25 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org