IOTA/IOTA-ES occultation update for (405) Thia / TYC 1864-00383-1 event on 2009 Sep 11, 09:16 UT Visible from Summary ------- On 2009 Sep 11 UT, the 125 km diameter asteroid (405) Thia will occult a 11.6 mag star in the constellation Gemini for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 2.6 mag to 14.1 mag (the magnitude of the asteroid) for at most 5.6 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: 98 * date and approx. time of event: 2009 Sep 11, 09:13 - 2009 Sep 11, 09:15 UT * magnitude of target star: 11.6 * magnitude drop [mag]: 2.6 * estimated maximum duration [s]: 5.6 * Moon: 58 % sunlit, 23° distance * Sun: 77° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 162 * 1 sigma uncertainty interval [path widths]: +/- 0.36 * 1 sigma uncertainty interval [seconds]: +/- 2.8 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .031 +/- .021) * 1 sigma uncertainty ellipse (major, minor, PA): ( .032", .021", 92° ) * approx speed of asteroid's shadow [km/s]: 22.2525 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1864-00383-1 by 405 Thia on 2009 Sep 11 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 -151 0 0 43 17 49 9 13 7 0 56 -41 .. .. .. 44 11 37 .. .. .. 44 50 53 -150 0 0 43 47 19 9 13 7 1 57 -41 42 54 19 44 41 8 42 16 39 45 20 26 -149 0 0 44 16 37 9 13 8 2 58 -41 43 23 37 45 10 28 42 45 56 45 49 47 -148 0 0 44 45 44 9 13 8 3 59 -40 43 52 42 45 39 35 43 15 1 46 18 55 -147 0 0 45 14 37 9 13 8 4 59 -40 44 21 35 46 8 29 43 43 53 46 47 48 -146 0 0 45 43 16 9 13 9 5 60 -40 44 50 14 46 37 8 44 12 33 47 16 27 -145 0 0 46 11 40 9 13 9 6 61 -39 45 18 39 47 5 31 44 40 58 47 44 50 -144 0 0 46 39 49 9 13 10 6 61 -39 45 46 49 47 33 39 45 9 9 48 12 57 -143 0 0 47 7 42 9 13 10 7 62 -38 46 14 44 48 1 30 45 37 4 48 40 47 -142 0 0 47 35 18 9 13 11 8 63 -38 46 42 21 48 29 4 46 4 44 49 8 19 -141 0 0 48 2 36 9 13 12 9 64 -38 47 9 42 48 56 19 46 32 6 49 35 32 -140 0 0 48 29 36 9 13 13 10 64 -37 47 36 45 49 23 16 46 59 11 50 2 27 -139 0 0 48 56 17 9 13 14 10 65 -37 48 3 29 49 49 53 47 25 57 50 29 2 -138 0 0 49 22 38 9 13 15 11 66 -36 48 29 55 50 16 11 47 52 26 50 55 16 -137 0 0 49 48 40 9 13 16 12 67 -36 48 56 1 50 42 8 48 18 34 51 21 10 -136 0 0 50 14 22 9 13 17 13 68 -35 49 21 47 51 7 45 48 44 24 51 46 43 -135 0 0 50 39 42 9 13 18 14 68 -35 49 47 12 51 33 0 49 9 53 52 11 55 -134 0 0 51 4 42 9 13 19 14 69 -34 50 12 17 51 57 54 49 35 1 52 36 44 -133 0 0 51 29 19 9 13 20 15 70 -34 50 37 1 52 22 26 49 59 49 53 1 11 -132 0 0 51 53 35 9 13 22 16 71 -33 51 1 23 52 46 35 50 24 15 53 25 16 -131 0 0 52 17 29 9 13 23 16 72 -33 51 25 23 53 10 22 50 48 20 53 48 57 -130 0 0 52 41 0 9 13 24 17 73 -32 51 49 1 53 33 46 51 12 2 54 12 16 -129 0 0 53 4 8 9 13 26 18 73 -32 52 12 16 53 56 46 51 35 22 54 35 11 -128 0 0 53 26 53 9 13 27 18 74 -31 52 35 8 54 19 24 51 58 20 54 57 42 -127 0 0 53 49 15 9 13 29 19 75 -31 52 57 38 54 41 38 52 20 55 55 19 50 -126 0 0 54 11 13 9 13 30 20 76 -30 53 19 45 55 3 28 52 43 7 55 41 34 -125 0 0 54 32 49 9 13 32 20 77 -30 53 41 28 55 24 54 53 4 56 56 2 54 -124 0 0 54 54 0 9 13 33 21 78 -29 54 2 48 55 45 57 53 26 22 56 23 50 -123 0 0 55 14 48 9 13 35 22 79 -29 54 23 45 56 6 36 53 47 25 56 44 22 -122 0 0 55 35 12 9 13 37 22 80 -28 54 44 18 56 26 50 54 8 4 57 4 30 -121 0 0 55 55 12 9 13 38 23 81 -28 55 4 27 56 46 41 54 28 20 57 24 14 -120 0 0 56 14 49 9 13 40 24 82 -27 55 24 13 57 6 8 54 48 12 57 43 34 -119 0 0 56 34 2 9 13 42 24 82 -27 55 43 35 57 25 11 55 7 41 58 2 29 -118 0 0 56 52 51 9 13 43 25 83 -26 56 2 34 57 43 51 55 26 47 58 21 1 -117 0 0 57 11 17 9 13 45 25 84 -26 56 21 10 58 2 6 55 45 29 58 39 9 -116 0 0 57 29 19 9 13 47 26 85 -25 56 39 22 58 19 58 56 3 48 58 56 54 -115 0 0 57 46 58 9 13 49 27 86 -25 56 57 10 58 37 27 56 21 43 59 14 14 -114 0 0 58 4 14 9 13 50 27 87 -24 57 14 36 58 54 32 56 39 16 59 31 12 -113 0 0 58 21 6 9 13 52 28 88 -24 57 31 38 59 11 14 56 56 25 59 47 46 -112 0 0 58 37 35 9 13 54 28 89 -23 57 48 17 59 27 33 57 13 11 60 3 57 -111 0 0 58 53 41 9 13 56 29 90 -23 58 4 34 59 43 29 57 29 35 60 19 45 -110 0 0 59 9 25 9 13 58 29 91 -22 58 20 27 59 59 2 57 45 35 60 35 10 -109 0 0 59 24 46 9 14 0 30 92 -22 58 35 59 60 14 12 58 1 13 60 50 13 -108 0 0 59 39 45 9 14 1 30 93 -21 58 51 7 60 29 0 58 16 29 61 4 53 -107 0 0 59 54 21 9 14 3 31 94 -21 59 5 54 60 43 27 58 31 23 61 19 12 -106 0 0 60 8 36 9 14 5 31 95 -20 59 20 18 60 57 31 58 45 54 61 33 8 -105 0 0 60 22 28 9 14 7 32 96 -20 59 34 21 61 11 13 59 0 4 61 46 43 -104 0 0 60 36 0 9 14 9 32 97 -19 59 48 2 61 24 34 59 13 52 61 59 56 -103 0 0 60 49 9 9 14 11 33 99 -19 60 1 21 61 37 33 59 27 18 62 12 48 -102 0 0 61 1 58 9 14 13 33 100 -18 60 14 20 61 50 12 59 40 23 62 25 19 -101 0 0 61 14 25 9 14 15 33 101 -18 60 26 57 62 2 30 59 53 7 62 37 29 -100 0 0 61 26 32 9 14 17 34 102 -18 60 39 13 62 14 27 60 5 30 62 49 19 - 99 0 0 61 38 19 9 14 18 34 103 -17 60 51 9 62 26 3 60 17 32 63 0 48 - 98 0 0 61 49 45 9 14 20 35 104 -17 61 2 44 62 37 20 60 29 14 63 11 58 - 97 0 0 62 0 51 9 14 22 35 105 -16 61 14 0 62 48 16 60 40 36 63 22 47 - 96 0 0 62 11 37 9 14 24 36 106 -16 61 24 55 62 58 53 60 51 37 63 33 17 - 95 0 0 62 22 4 9 14 26 36 107 -15 61 35 30 63 9 11 61 2 19 63 43 28 - 94 0 0 62 32 11 9 14 28 36 108 -15 61 45 46 63 19 9 61 12 40 63 53 20 - 93 0 0 62 41 59 9 14 30 37 109 -14 61 55 42 63 28 48 61 22 43 64 2 52 - 92 0 0 62 51 27 9 14 32 37 111 -14 62 5 19 63 38 8 61 32 26 64 12 6 - 91 0 0 63 0 38 9 14 34 37 112 -13 62 14 38 63 47 10 61 41 50 64 21 2 - 90 0 0 63 9 29 9 14 36 38 113 -13 62 23 37 63 55 53 61 50 55 64 29 39 - 89 0 0 63 18 2 9 14 38 38 114 -13 62 32 18 64 4 19 61 59 41 64 37 58 - 88 0 0 63 26 17 9 14 39 39 115 -12 62 40 41 64 12 26 62 8 9 64 45 59 - 87 0 0 63 34 14 9 14 41 39 116 -12 62 48 45 64 20 15 62 16 19 64 53 43 - 86 0 0 63 41 54 9 14 43 39 117 -11 62 56 32 64 27 47 62 24 10 65 1 10 - 85 0 0 63 49 15 9 14 45 40 119 -11 63 4 0 64 35 1 62 31 44 65 8 19 - 84 0 0 63 56 20 9 14 47 40 120 -10 63 11 11 64 41 59 62 38 59 65 15 11 - 83 0 0 64 3 6 9 14 49 40 121 -10 63 18 4 64 48 39 62 45 57 65 21 46 - 82 0 0 64 9 36 9 14 51 41 122 -9 63 24 41 64 55 2 62 52 38 65 28 5 - 81 0 0 64 15 49 9 14 53 41 123 -9 63 31 0 65 1 9 62 59 1 65 34 7 - 80 0 0 64 21 45 9 14 55 41 125 -9 63 37 2 65 6 59 63 5 7 65 39 52 - 79 0 0 64 27 25 9 14 57 41 126 -8 63 42 47 65 12 33 63 10 56 65 45 22 - 78 0 0 64 32 48 9 14 59 42 127 -8 63 48 15 65 17 50 63 16 28 65 50 35 - 77 0 0 64 37 55 9 15 1 42 128 -7 63 53 27 65 22 52 63 21 44 65 55 33 - 76 0 0 64 42 45 9 15 3 42 129 -7 63 58 22 65 27 37 63 26 42 66 0 14 - 75 0 0 64 47 20 9 15 5 43 131 -6 64 3 1 65 32 7 63 31 25 66 4 41 - 74 0 0 64 51 38 9 15 6 43 132 -6 64 7 24 65 36 21 63 35 51 66 8 51 - 73 0 0 64 55 41 9 15 8 43 133 -6 64 11 31 65 40 19 63 40 0 66 12 46 - 72 0 0 64 59 28 9 15 10 43 134 -5 64 15 22 65 44 2 63 43 54 66 16 26 - 71 0 0 65 2 59 9 15 12 44 136 -5 64 18 57 65 47 30 63 47 31 66 19 51 - 70 0 0 65 6 15 9 15 14 44 137 -4 64 22 16 65 50 42 63 50 53 66 23 1 - 69 0 0 65 9 15 9 15 16 44 138 -4 64 25 19 65 53 39 63 53 59 66 25 55 - 68 0 0 65 12 0 9 15 18 44 139 -4 64 28 7 65 56 21 63 56 48 66 28 35 - 67 0 0 65 14 30 9 15 20 45 141 -3 64 30 40 65 58 48 63 59 23 66 31 0 - 66 0 0 65 16 44 9 15 22 45 142 -3 64 32 56 66 1 0 64 1 41 66 33 10 - 65 0 0 65 18 43 9 15 24 45 143 -2 64 34 58 66 2 57 64 3 44 66 35 6 - 64 0 0 65 20 27 9 15 26 45 144 -2 64 36 44 66 4 39 64 5 31 66 36 47 - 63 0 0 65 21 56 9 15 28 46 146 -1 64 38 14 66 6 7 64 7 3 66 38 13 - 62 0 0 65 23 10 9 15 30 46 147 -1 64 39 30 66 7 19 64 8 19 66 39 24 - 61 0 0 65 24 10 9 15 32 46 148 -1 64 40 30 66 8 17 64 9 20 66 40 22 - 60 0 0 65 24 54 9 15 34 46 150 0 64 41 15 66 9 0 64 10 6 66 41 4 Uncertainty in time = +/- 3 secs [Prediction of 2008 Mar 20.0] Data for the target star ------------------------ * name: TYC 1864-00383-1 * constellation : Gemini * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 06 07 01.4835 DE: +24 08 04.074 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .029, .019 ) * V mag [mag]: 11.6 * B mag [mag]: 11.9 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (405) Thia approx. diameter [km]: 125 approx. diameter ["]: .058 distance from Earth [AU]: 2.96600 * orbital information: orbit source: Preston date of fit: 2008 Mar 20 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 715 number of rejected observations: 83 time covered by the observations: 1903 Jun 27 - 2007 Nov 20 1 sigma uncertainty ellipse (major, minor, PA): 0.012, 0.010, 106° remarks: * orbital elements for (405) Thia : Mean anomaly = 250.90111095 deg Arg. of pericenter = 309.03872197 deg Long. of node = 255.29888193 deg Inclination = 11.95038056 deg Eccentricity = 0.24456789 Semimajor axis = 2.58360584 AU Perihelion dist = 1.95173881 AU Mag: H = 8.45, G = 0.15 Epoch of elements : MJD 55085.38700000 TDT (2009 Sep 11.387) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Sep 11 405 Thia 9h 16.8m UT 11.6 6 7 1.483 24 8 4.07TYC 1864-00383-1 11.9 14.1 125 5.6 2.966 2.691 -5.49 -37.9723 24.137 39.96 4.44 9.2799 0.09517 0.63104 12.42288 -1.85046 -0.00554 0.00008 2000 249.6225792009 9 6.00000309.038722255.298882 11.9503810.24456789 2.5836058 1.9517388 8.5 5.00.15 RATE 2.3733660 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.032 0.021 92 1.36 0.021 0 54545.5020090911_0383-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 20, 13:11 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org