IOTA/IOTA-ES occultation update for (35) Leukothea / TYC 1889-00005-1 event on 2009 Aug 01, 11:42 UT Visible from Summary ------- On 2009 Aug 01 UT, the 103 km diameter asteroid (35) Leukothea will occult a 10.4 mag star in the constellation Auriga for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 4.4 mag to 14.8 mag (the magnitude of the asteroid) for at most 2.6 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: 87 * date and approx. time of event: 2009 Aug 01, 11:40 - 2009 Aug 01, 11:40 UT * magnitude of target star: 10.4 * magnitude drop [mag]: 4.4 * estimated maximum duration [s]: 2.6 * Moon: 83 % sunlit, 167° distance * Sun: 37° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 112 * 1 sigma uncertainty interval [path widths]: +/- 0.57 * 1 sigma uncertainty interval [seconds]: +/- 1.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .020 +/- .020) * 1 sigma uncertainty ellipse (major, minor, PA): ( .020", .020", 91° ) * approx speed of asteroid's shadow [km/s]: 39.1378 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1889-00005-1 by 35 Leukothea on 2009 Aug 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 -133 0 0 19 54 38 11 40 7 1 58 -35 19 18 41 20 30 46 18 37 55 21 12 14 -132 0 0 20 30 6 11 40 7 2 59 -34 19 54 5 21 6 18 19 13 16 21 47 50 -131 0 0 21 5 38 11 40 7 3 59 -33 20 29 34 21 41 54 19 48 42 22 23 29 -130 0 0 21 41 13 11 40 8 4 59 -32 21 5 6 22 17 31 20 24 10 22 59 10 -129 0 0 22 16 48 11 40 8 5 60 -31 21 40 39 22 53 10 20 59 40 23 34 52 -128 0 0 22 52 24 11 40 8 6 60 -30 22 16 12 23 28 48 21 35 11 24 10 33 -127 0 0 23 27 59 11 40 9 7 61 -29 22 51 45 24 4 25 22 10 41 24 46 12 -126 0 0 24 3 32 11 40 9 8 61 -28 23 27 16 24 40 0 22 46 9 25 21 49 -125 0 0 24 39 1 11 40 10 10 61 -27 24 2 43 25 15 30 23 21 35 25 57 22 -124 0 0 25 14 25 11 40 10 11 62 -25 24 38 6 25 50 56 23 56 56 26 32 49 -123 0 0 25 49 43 11 40 11 12 62 -24 25 13 23 26 26 15 24 32 12 27 8 10 -122 0 0 26 24 55 11 40 12 13 63 -23 25 48 34 27 1 28 25 7 22 27 43 23 -121 0 0 26 59 58 11 40 12 14 63 -22 26 23 37 27 36 32 25 42 25 28 18 27 -120 0 0 27 34 52 11 40 13 15 64 -21 26 58 31 28 11 26 26 17 18 28 53 22 -119 0 0 28 9 36 11 40 14 16 64 -20 27 33 15 28 46 10 26 52 2 29 28 6 -118 0 0 28 44 8 11 40 15 17 65 -19 28 7 47 29 20 42 27 26 35 30 2 37 -117 0 0 29 18 28 11 40 16 18 65 -18 28 42 8 29 55 1 28 0 57 30 36 55 -116 0 0 29 52 35 11 40 17 19 66 -17 29 16 15 30 29 6 28 35 5 31 11 0 -115 0 0 30 26 26 11 40 18 20 66 -16 29 50 8 31 2 56 29 8 59 31 44 49 -114 0 0 31 0 3 11 40 19 21 67 -15 30 23 46 31 36 31 29 42 39 32 18 21 -113 0 0 31 33 22 11 40 20 22 68 -14 30 57 8 32 9 49 30 16 2 32 51 37 -112 0 0 32 6 25 11 40 22 23 68 -13 31 30 12 32 42 50 30 49 9 33 24 35 -111 0 0 32 39 9 11 40 23 24 69 -12 32 2 59 33 15 31 31 21 59 33 57 14 -110 0 0 33 11 35 11 40 24 25 69 -11 32 35 27 33 47 54 31 54 30 34 29 34 -109 0 0 33 43 40 11 40 25 26 70 -10 33 7 35 34 19 57 32 26 41 35 1 33 -108 0 0 34 15 25 11 40 27 27 71 -9 33 39 23 34 51 38 32 58 33 35 33 11 -107 0 0 34 46 48 11 40 28 28 71 -8 34 10 50 35 22 58 33 30 3 36 4 27 -106 0 0 35 17 50 11 40 30 29 72 -7 34 41 55 35 53 56 34 1 13 36 35 21 -105 0 0 35 48 29 11 40 31 30 73 -6 35 12 38 36 24 31 34 32 0 37 5 51 -104 0 0 36 18 45 11 40 33 31 74 -5 35 42 58 36 54 43 35 2 24 37 35 58 -103 0 0 36 48 37 11 40 34 32 74 -4 36 12 54 37 24 31 35 32 25 38 5 40 -102 0 0 37 18 4 11 40 36 33 75 -3 36 42 26 37 53 54 36 2 3 38 34 58 -101 0 0 37 47 7 11 40 37 33 76 -2 37 11 34 38 22 52 36 31 15 39 3 51 -100 0 0 38 15 45 11 40 39 34 77 -1 37 40 17 38 51 24 37 0 3 39 32 17 - 99 0 0 38 43 57 11 40 41 35 78 0 38 8 34 39 19 31 37 28 26 40 0 18 Uncertainty in time = +/- 1 secs [Prediction of 2008 Apr 25.0] Data for the target star ------------------------ * name: TYC 1889-00005-1 * constellation : Auriga * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 06 12 19.8413 DE: +29 51 01.414 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .017, .018 ) * V mag [mag]: 10.4 * B mag [mag]: 11.4 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (35) Leukothea approx. diameter [km]: 103 approx. diameter ["]: .035 distance from Earth [AU]: 4.02500 * orbital information: orbit source: Preston date of fit: 2008 Apr 25 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1132 number of rejected observations: 103 time covered by the observations: 1907 Apr 04 - 2008 Jan 12 1 sigma uncertainty ellipse (major, minor, PA): 0.011, 0.009, 95° remarks: * orbital elements for (35) Leukothea : Mean anomaly = 257.58539173 deg Arg. of pericenter = 213.91912952 deg Long. of node = 353.80285016 deg Inclination = 7.93477942 deg Eccentricity = 0.22758608 Semimajor axis = 2.99143477 AU Perihelion dist = 2.31062586 AU Mag: H = 8.45, G = 0.15 Epoch of elements : MJD 55044.48800000 TDT (2009 Aug 01.488) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Aug 1 35 Leukothea 11h 42.6m UT 10.4 6 12 19.841 29 51 1.41TYC 1889-00005-1 11.4 14.8 103 2.6 4.025 3.710 0.98 -32.7873 29.850 5.94 17.91 11.7101 -0.00749 0.40137 22.08591 0.44896 -0.00337 0.00058 2000 256.7304482009 728.00000213.919130353.802850 7.9347790.22758608 2.9914348 2.3106259 8.5 5.00.15 RATE 1.9049550 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.020 0.020 91 1.57 0.020 0 54581.5020090801_0005-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 25, 07:47 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org