IOTA/IOTA-ES occultation update for (18) Melpomene / TYC 0023-00248-1 event on 2009 Aug 04, 18:49 UT Visible from N China, E Russia Summary ------- On 2009 Aug 04 UT, the 141 km diameter asteroid (18) Melpomene will occult a 9.9 mag star in the constellation Pisces for observers along a path across N China, E Russia. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.5 mag to 9.3 mag (the magnitude of the asteroid) for at most 13.1 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: 100 * date and approx. time of event: 2009 Aug 04, 18:42 - 2009 Aug 04, 18:50 UT * midpoint of event [JD]: 2455048.284825 * magnitude of target star: 9.9 * magnitude drop [mag]: 0.5 * estimated maximum duration [s]: 13.1 * Moon: 99 % sunlit, 79° distance * Sun: 114° distance * rough path description: N China, E Russia The occultation path -------------------- * approximate projected width [km]: 191 * 1 sigma uncertainty interval [path widths]: +/- 0.15 * 1 sigma uncertainty interval [seconds]: +/- 2.2 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .028 +/- .024) * 1 sigma uncertainty ellipse (major, minor, PA): ( .028", .024", 83° ) * approx speed of asteroid's shadow [km/s]: 10.7327 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 0023-00248-1 by 18 Melpomene on 2009 Aug 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 ' " Latitude Latitude Latitude Latitude 52 0 0 49 49 44 18 42 51 0 86 -19 48 58 13 50 41 57 48 42 54 50 57 46 53 0 0 49 52 28 18 42 51 1 87 -19 49 0 58 50 44 41 48 45 39 51 0 29 54 0 0 49 55 5 18 42 51 2 88 -19 49 3 36 50 47 17 48 48 17 51 3 5 55 0 0 49 57 35 18 42 51 2 89 -19 49 6 7 50 49 46 48 50 48 51 5 34 56 0 0 49 59 58 18 42 52 3 89 -20 49 8 30 50 52 8 48 53 12 51 7 56 57 0 0 50 2 14 18 42 52 4 90 -20 49 10 47 50 54 23 48 55 29 51 10 11 58 0 0 50 4 22 18 42 53 4 91 -20 49 12 56 50 56 31 48 57 38 51 12 18 59 0 0 50 6 23 18 42 54 5 92 -20 49 14 58 50 58 31 48 59 40 51 14 19 60 0 0 50 8 17 18 42 55 6 92 -20 49 16 53 51 0 25 49 1 35 51 16 12 61 0 0 50 10 4 18 42 56 6 93 -21 49 18 40 51 2 11 49 3 23 51 17 58 62 0 0 50 11 44 18 42 57 7 94 -21 49 20 20 51 3 50 49 5 3 51 19 36 63 0 0 50 13 16 18 42 58 8 95 -21 49 21 53 51 5 21 49 6 36 51 21 8 64 0 0 50 14 41 18 42 59 8 96 -21 49 23 18 51 6 46 49 8 1 51 22 32 65 0 0 50 15 58 18 43 0 9 96 -21 49 24 36 51 8 3 49 9 20 51 23 48 66 0 0 50 17 8 18 43 2 9 97 -22 49 25 47 51 9 12 49 10 30 51 24 58 67 0 0 50 18 11 18 43 3 10 98 -22 49 26 50 51 10 14 49 11 33 51 26 0 68 0 0 50 19 6 18 43 5 11 99 -22 49 27 45 51 11 9 49 12 29 51 26 55 69 0 0 50 19 54 18 43 7 11 100 -22 49 28 34 51 11 56 49 13 18 51 27 42 70 0 0 50 20 34 18 43 9 12 100 -22 49 29 14 51 12 36 49 13 58 51 28 22 71 0 0 50 21 7 18 43 10 13 101 -22 49 29 48 51 13 9 49 14 32 51 28 54 72 0 0 50 21 32 18 43 12 13 102 -22 49 30 13 51 13 34 49 14 57 51 29 19 73 0 0 50 21 50 18 43 15 14 103 -22 49 30 31 51 13 52 49 15 16 51 29 37 74 0 0 50 22 1 18 43 17 15 104 -22 49 30 42 51 14 2 49 15 26 51 29 47 75 0 0 50 22 3 18 43 19 15 104 -23 49 30 45 51 14 4 49 15 29 51 29 49 76 0 0 50 21 59 18 43 22 16 105 -23 49 30 40 51 13 59 49 15 25 51 29 44 77 0 0 50 21 46 18 43 24 16 106 -23 49 30 28 51 13 47 49 15 13 51 29 32 78 0 0 50 21 27 18 43 27 17 107 -23 49 30 8 51 13 27 49 14 53 51 29 12 79 0 0 50 20 59 18 43 29 18 108 -23 49 29 41 51 13 0 49 14 26 51 28 44 80 0 0 50 20 24 18 43 32 18 108 -23 49 29 6 51 12 25 49 13 51 51 28 10 81 0 0 50 19 42 18 43 35 19 109 -23 49 28 24 51 11 42 49 13 8 51 27 27 82 0 0 50 18 52 18 43 38 19 110 -23 49 27 34 51 10 52 49 12 18 51 26 37 83 0 0 50 17 54 18 43 41 20 111 -23 49 26 36 51 9 55 49 11 20 51 25 40 84 0 0 50 16 49 18 43 44 21 112 -23 49 25 31 51 8 50 49 10 15 51 24 35 85 0 0 50 15 36 18 43 48 21 113 -23 49 24 18 51 7 37 49 9 2 51 23 22 86 0 0 50 14 16 18 43 51 22 114 -23 49 22 57 51 6 17 49 7 41 51 22 2 87 0 0 50 12 48 18 43 55 23 114 -23 49 21 29 51 4 49 49 6 13 51 20 35 88 0 0 50 11 13 18 43 58 23 115 -23 49 19 53 51 3 14 49 4 37 51 19 0 89 0 0 50 9 30 18 44 2 24 116 -23 49 18 10 51 1 32 49 2 54 51 17 17 90 0 0 50 7 39 18 44 5 24 117 -22 49 16 19 50 59 42 49 1 3 51 15 27 91 0 0 50 5 41 18 44 9 25 118 -22 49 14 21 50 57 44 48 59 5 51 13 29 92 0 0 50 3 35 18 44 13 26 119 -22 49 12 15 50 55 39 48 56 58 51 11 24 93 0 0 50 1 22 18 44 17 26 120 -22 49 10 1 50 53 26 48 54 45 51 9 12 94 0 0 49 59 2 18 44 21 27 121 -22 49 7 40 50 51 6 48 52 24 51 6 52 95 0 0 49 56 34 18 44 26 27 122 -22 49 5 11 50 48 38 48 49 55 51 4 25 96 0 0 49 53 58 18 44 30 28 123 -22 49 2 35 50 46 3 48 47 19 51 1 50 97 0 0 49 51 15 18 44 34 28 124 -22 48 59 52 50 43 21 48 44 35 50 59 8 98 0 0 49 48 25 18 44 39 29 125 -21 48 57 1 50 40 31 48 41 44 50 56 18 99 0 0 49 45 27 18 44 43 30 126 -21 48 54 2 50 37 34 48 38 45 50 53 21 100 0 0 49 42 22 18 44 48 30 127 -21 48 50 56 50 34 30 48 35 39 50 50 17 101 0 0 49 39 9 18 44 53 31 128 -21 48 47 43 50 31 18 48 32 25 50 47 5 102 0 0 49 35 49 18 44 57 31 129 -21 48 44 22 50 27 58 48 29 4 50 43 46 103 0 0 49 32 22 18 45 2 32 130 -21 48 40 54 50 24 32 48 25 36 50 40 20 104 0 0 49 28 47 18 45 7 32 131 -20 48 37 19 50 20 58 48 22 1 50 36 46 105 0 0 49 25 5 18 45 12 33 132 -20 48 33 36 50 17 17 48 18 18 50 33 6 106 0 0 49 21 16 18 45 17 33 133 -20 48 29 47 50 13 29 48 14 28 50 29 18 107 0 0 49 17 20 18 45 23 34 134 -20 48 25 49 50 9 34 48 10 30 50 25 23 108 0 0 49 13 17 18 45 28 34 135 -19 48 21 45 50 5 31 48 6 26 50 21 21 109 0 0 49 9 6 18 45 33 35 136 -19 48 17 34 50 1 22 48 2 14 50 17 11 110 0 0 49 4 49 18 45 39 35 137 -19 48 13 15 49 57 5 47 57 55 50 12 55 111 0 0 49 0 24 18 45 44 36 138 -19 48 8 50 49 52 42 47 53 30 50 8 32 112 0 0 48 55 53 18 45 50 36 139 -18 48 4 17 49 48 11 47 48 57 50 4 1 113 0 0 48 51 14 18 45 56 37 140 -18 47 59 38 49 43 34 47 44 17 49 59 24 114 0 0 48 46 29 18 46 1 37 141 -18 47 54 51 49 38 49 47 39 30 49 54 40 115 0 0 48 41 37 18 46 7 38 142 -17 47 49 58 49 33 58 47 34 37 49 49 49 116 0 0 48 36 38 18 46 13 38 144 -17 47 44 58 49 29 0 47 29 36 49 44 52 117 0 0 48 31 32 18 46 19 39 145 -17 47 39 51 49 23 56 47 24 29 49 39 47 118 0 0 48 26 19 18 46 25 39 146 -16 47 34 38 49 18 44 47 19 15 49 34 36 119 0 0 48 21 0 18 46 32 40 147 -16 47 29 18 49 13 26 47 13 55 49 29 19 120 0 0 48 15 35 18 46 38 40 148 -16 47 23 51 49 8 2 47 8 28 49 23 55 121 0 0 48 10 3 18 46 44 41 150 -15 47 18 18 49 2 31 47 2 55 49 18 24 122 0 0 48 4 24 18 46 51 41 151 -15 47 12 38 48 56 54 46 57 15 49 12 47 123 0 0 47 58 39 18 46 57 42 152 -15 47 6 52 48 51 10 46 51 28 49 7 4 124 0 0 47 52 48 18 47 3 42 153 -14 47 1 0 48 45 20 46 45 36 49 1 14 125 0 0 47 46 51 18 47 10 42 155 -14 46 55 2 48 39 24 46 39 37 48 55 18 126 0 0 47 40 47 18 47 17 43 156 -13 46 48 57 48 33 21 46 33 32 48 49 17 127 0 0 47 34 38 18 47 23 43 157 -13 46 42 47 48 27 13 46 27 21 48 43 9 128 0 0 47 28 23 18 47 30 43 159 -12 46 36 30 48 20 59 46 21 5 48 36 55 129 0 0 47 22 1 18 47 37 44 160 -12 46 30 8 48 14 39 46 14 42 48 30 35 130 0 0 47 15 34 18 47 44 44 161 -12 46 23 40 48 8 13 46 8 13 48 24 9 131 0 0 47 9 1 18 47 51 44 163 -11 46 17 6 48 1 41 46 1 39 48 17 38 132 0 0 47 2 23 18 47 58 45 164 -11 46 10 26 47 55 4 45 54 59 48 11 1 133 0 0 46 55 39 18 48 5 45 165 -10 46 3 41 47 48 21 45 48 14 48 4 19 134 0 0 46 48 50 18 48 12 45 167 -10 45 56 51 47 41 33 45 41 23 47 57 31 135 0 0 46 41 55 18 48 19 46 168 -9 45 49 55 47 34 40 45 34 28 47 50 38 136 0 0 46 34 56 18 48 27 46 170 -9 45 42 55 47 27 41 45 27 26 47 43 39 137 0 0 46 27 51 18 48 34 46 171 -8 45 35 49 47 20 37 45 20 20 47 36 36 138 0 0 46 20 41 18 48 41 46 173 -8 45 28 38 47 13 28 45 13 9 47 29 28 139 0 0 46 13 26 18 48 48 46 174 -7 45 21 22 47 6 15 45 5 53 47 22 14 140 0 0 46 6 7 18 48 56 47 176 -7 45 14 2 46 58 56 44 58 33 47 14 56 141 0 0 45 58 43 18 49 3 47 177 -6 45 6 37 46 51 33 44 51 7 47 7 34 142 0 0 45 51 15 18 49 11 47 179 -5 44 59 7 46 44 6 44 43 38 47 0 6 143 0 0 45 43 42 18 49 18 47 180 -5 44 51 34 46 36 34 44 36 4 46 52 35 144 0 0 45 36 5 18 49 26 47 182 -4 44 43 56 46 28 58 44 28 25 46 44 59 145 0 0 45 28 23 18 49 33 47 183 -4 44 36 14 46 21 18 44 20 43 46 37 19 146 0 0 45 20 38 18 49 41 47 185 -3 44 28 28 46 13 33 44 12 57 46 29 35 147 0 0 45 12 49 18 49 49 47 186 -3 44 20 38 46 5 45 44 5 7 46 21 47 148 0 0 45 4 57 18 49 56 47 188 -2 44 12 44 45 57 53 43 57 13 46 13 56 149 0 0 44 57 0 18 50 4 48 189 -1 44 4 47 45 49 58 43 49 16 46 6 0 150 0 0 44 49 1 18 50 12 48 191 -1 43 56 47 45 41 59 43 41 15 45 58 2 151 0 0 44 40 58 18 50 20 47 192 0 43 48 43 45 33 57 43 33 11 45 50 0 Uncertainty in time = +/- 2 secs [Prediction of 2008 Apr 28.0] Data for the target star ------------------------ * name: TYC 0023-00248-1 * constellation : Pisces * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 01 14 13.4521 DE: +02 40 53.234 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .020, .021 ) * V mag [mag]: 9.9 * B mag [mag]: 10.3 * Apparent position with proper motion RA(deg): 18.6858642924 DE(deg): 2.7354357416 * Equation of equinoxes (radians) : 0.000072107117007 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (18) Melpomene approx. diameter [km]: 141 approx. diameter ["]: .166 distance from Earth [AU]: 1.17400 * orbital information: orbit source: Preston date of fit: 2008 Mar 20 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 3744 number of rejected observations: 304 time covered by the observations: 1901 Aug 14 - 2008 Feb 17 1 sigma uncertainty ellipse (major, minor, PA): 0.020, 0.012, 76° remarks: * orbital elements for (18) Melpomene : Mean anomaly = 340.82653650 deg Arg. of pericenter = 227.76939281 deg Long. of node = 150.51410584 deg Inclination = 10.12890761 deg Eccentricity = 0.21837390 Semimajor axis = 2.29588568 AU Perihelion dist = 1.79452417 AU Mag: H = 6.51, G = 0.25 Epoch of elements : MJD 55047.78500000 TDT (2009 Aug 04.785) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Aug 4 18 Melpomene 18h 50.1m UT 9.9 1 14 13.452 2 40 53.23TYC 0023-00248-1 10.3 9.3 141 13.1 1.174 3.003 -5.77 142.5512 2.684 -101.02 17.05 18.8358 0.08567 0.66750 6.00894 -0.76825 -0.00415 -0.00152 2000 338.6208832009 728.00000227.769393150.514106 10.1289080.21837390 2.2958857 1.7945242 6.5 5.00.25 RATE 2.8332100 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.028 0.024 83 1.15 0.024 0 54584.5020090804_0248-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 28, 02:27 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org