IOTA/IOTA-ES occultation update for (31) Euphrosyne / TYC 1986-00436-1 event on 2012 Nov 23, 19:34 UT Visible from Japan, Russia, China Summary ------- On 2012 Nov 23 UT, the 277 km diameter asteroid (31) Euphrosyne will occult a 11.0 mag star in the constellation Coma Berenices for observers along a path across Japan, Russia, China. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.4 mag to 12.1 mag (the magnitude of the asteroid) for at most 10.7 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: 99 * date and approx. time of event: 2012 Nov 23, 19:30 - 2012 Nov 23, 19:33 UT * geocentric midpoint of event [JD]: 2456255.31592083 * magnitude of target star: 11.0 * magnitude drop [mag]: 1.4 * estimated maximum duration [s]: 10.7 * Moon: 81 % sunlit, 149° distance * Sun: 72° distance * rough path description: Japan, Russia, China The occultation path -------------------- * approximate projected width [km]: 287 * 1 sigma uncertainty interval [path widths]: +/- 0.29 * 1 sigma uncertainty interval [seconds]: +/- 1.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .022 +/- .042) * 1 sigma uncertainty ellipse (major, minor, PA): ( .042", .021", 177° ) * approx speed of asteroid's shadow [km/s]: 25.9011 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1986-00436-1 by 31 Euphrosyne on 2012 Nov 23 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 82 0 0 27 47 47 19 30 58 0 63 -72 .. .. .. 29 15 48 .. .. .. 30 7 12 83 0 0 28 15 23 19 30 58 1 63 -71 26 48 12 29 43 15 25 57 55 30 34 32 84 0 0 28 42 38 19 30 58 2 63 -70 27 15 37 30 10 19 26 25 25 31 1 31 85 0 0 29 9 31 19 30 58 3 64 -69 27 42 40 30 37 2 26 52 34 31 28 7 86 0 0 29 36 2 19 30 59 4 64 -68 28 9 22 31 3 22 27 19 22 31 54 20 87 0 0 30 2 10 19 30 59 5 65 -67 28 35 41 31 29 19 27 45 47 32 20 11 88 0 0 30 27 56 19 31 0 6 65 -66 29 1 37 31 54 53 28 11 50 32 45 38 89 0 0 30 53 18 19 31 0 7 66 -65 29 27 11 32 20 4 28 37 30 33 10 42 90 0 0 31 18 16 19 31 1 8 67 -64 29 52 21 32 44 50 29 2 46 33 35 22 91 0 0 31 42 51 19 31 1 9 67 -63 30 17 7 33 9 13 29 27 39 33 59 37 92 0 0 32 7 1 19 31 2 10 68 -62 30 41 29 33 33 11 29 52 8 34 23 28 93 0 0 32 30 47 19 31 3 11 68 -61 31 5 27 33 56 45 30 16 13 34 46 54 94 0 0 32 54 9 19 31 3 12 69 -61 31 29 1 34 19 53 30 39 53 35 9 56 95 0 0 33 17 5 19 31 4 13 69 -60 31 52 9 34 42 37 31 3 9 35 32 32 96 0 0 33 39 36 19 31 5 13 70 -59 32 14 53 35 4 56 31 26 0 35 54 43 97 0 0 34 1 43 19 31 6 14 70 -58 32 37 12 35 26 49 31 48 26 36 16 29 98 0 0 34 23 24 19 31 7 15 71 -57 32 59 5 35 48 17 32 10 27 36 37 50 99 0 0 34 44 39 19 31 8 16 72 -56 33 20 33 36 9 20 32 32 2 36 58 44 100 0 0 35 5 29 19 31 9 17 72 -55 33 41 36 36 29 57 32 53 12 37 19 14 101 0 0 35 25 53 19 31 11 18 73 -54 34 2 13 36 50 8 33 13 56 37 39 17 102 0 0 35 45 52 19 31 12 19 73 -53 34 22 24 37 9 54 33 34 14 37 58 55 103 0 0 36 5 24 19 31 13 20 74 -52 34 42 9 37 29 13 33 54 7 38 18 7 104 0 0 36 24 31 19 31 15 21 75 -52 35 1 29 37 48 7 34 13 33 38 36 54 105 0 0 36 43 12 19 31 16 21 75 -51 35 20 23 38 6 36 34 32 34 38 55 15 106 0 0 37 1 28 19 31 17 22 76 -50 35 38 50 38 24 38 34 51 9 39 13 10 107 0 0 37 19 17 19 31 19 23 76 -49 35 56 52 38 42 15 35 9 18 39 30 39 108 0 0 37 36 41 19 31 20 24 77 -48 36 14 28 38 59 26 35 27 1 39 47 42 109 0 0 37 53 39 19 31 22 25 78 -47 36 31 38 39 16 11 35 44 18 40 4 20 110 0 0 38 10 11 19 31 23 26 78 -47 36 48 22 39 32 31 36 1 9 40 20 33 111 0 0 38 26 17 19 31 25 26 79 -46 37 4 41 39 48 25 36 17 34 40 36 20 112 0 0 38 41 58 19 31 27 27 80 -45 37 20 33 40 3 54 36 33 33 40 51 41 113 0 0 38 57 13 19 31 28 28 80 -44 37 36 0 40 18 57 36 49 7 41 6 38 114 0 0 39 12 2 19 31 30 29 81 -43 37 51 1 40 33 35 37 4 14 41 21 8 115 0 0 39 26 26 19 31 32 30 82 -42 38 5 36 40 47 47 37 18 56 41 35 14 116 0 0 39 40 25 19 31 34 31 83 -42 38 19 46 41 1 35 37 33 12 41 48 55 117 0 0 39 53 58 19 31 36 31 83 -41 38 33 30 41 14 57 37 47 2 42 2 10 118 0 0 40 7 6 19 31 38 32 84 -40 38 46 48 41 27 54 38 0 27 42 15 1 119 0 0 40 19 49 19 31 39 33 85 -39 38 59 42 41 40 26 38 13 26 42 27 27 120 0 0 40 32 7 19 31 41 34 86 -39 39 12 10 41 52 34 38 26 0 42 39 28 121 0 0 40 43 59 19 31 43 34 86 -38 39 24 12 42 4 16 38 38 8 42 51 5 122 0 0 40 55 27 19 31 45 35 87 -37 39 35 50 42 15 34 38 49 52 43 2 17 123 0 0 41 6 30 19 31 47 36 88 -36 39 47 3 42 26 28 39 1 9 43 13 5 124 0 0 41 17 9 19 31 49 37 89 -35 39 57 50 42 36 57 39 12 2 43 23 29 125 0 0 41 27 23 19 31 52 38 89 -35 40 8 13 42 47 2 39 22 30 43 33 28 126 0 0 41 37 12 19 31 54 38 90 -34 40 18 11 42 56 42 39 32 33 43 43 4 127 0 0 41 46 37 19 31 56 39 91 -33 40 27 44 43 5 59 39 42 11 43 52 15 128 0 0 41 55 38 19 31 58 40 92 -32 40 36 53 43 14 51 39 51 24 44 1 3 129 0 0 42 4 14 19 32 0 41 93 -32 40 45 37 43 23 20 40 0 12 44 9 27 130 0 0 42 12 26 19 32 2 41 93 -31 40 53 56 43 31 25 40 8 36 44 17 27 131 0 0 42 20 14 19 32 5 42 94 -30 41 1 51 43 39 6 40 16 36 44 25 4 132 0 0 42 27 39 19 32 7 43 95 -29 41 9 22 43 46 23 40 24 10 44 32 17 133 0 0 42 34 39 19 32 9 43 96 -29 41 16 29 43 53 17 40 31 21 44 39 7 134 0 0 42 41 16 19 32 12 44 97 -28 41 23 12 43 59 47 40 38 7 44 45 34 135 0 0 42 47 28 19 32 14 45 98 -27 41 29 30 44 5 54 40 44 29 44 51 37 136 0 0 42 53 18 19 32 16 46 99 -26 41 35 25 44 11 38 40 50 27 44 57 18 137 0 0 42 58 43 19 32 19 46 99 -26 41 40 56 44 16 58 40 56 0 45 2 35 138 0 0 43 3 45 19 32 21 47 100 -25 41 46 3 44 21 55 41 1 10 45 7 29 139 0 0 43 8 24 19 32 24 48 101 -24 41 50 46 44 26 30 41 5 55 45 12 1 140 0 0 43 12 39 19 32 26 48 102 -24 41 55 5 44 30 41 41 10 17 45 16 10 141 0 0 43 16 31 19 32 28 49 103 -23 41 59 0 44 34 29 41 14 15 45 19 56 142 0 0 43 19 59 19 32 31 50 104 -22 42 2 32 44 37 54 41 17 48 45 23 19 143 0 0 43 23 5 19 32 33 51 105 -21 42 5 41 44 40 56 41 20 58 45 26 19 144 0 0 43 25 47 19 32 36 51 106 -21 42 8 25 44 43 36 41 23 45 45 28 57 145 0 0 43 28 6 19 32 39 52 107 -20 42 10 46 44 45 52 41 26 7 45 31 12 146 0 0 43 30 1 19 32 41 53 108 -19 42 12 44 44 47 46 41 28 6 45 33 5 147 0 0 43 31 34 19 32 44 53 109 -18 42 14 18 44 49 17 41 29 41 45 34 35 148 0 0 43 32 43 19 32 46 54 110 -18 42 15 29 44 50 25 41 30 52 45 35 42 149 0 0 43 33 30 19 32 49 55 111 -17 42 16 16 44 51 11 41 31 40 45 36 27 150 0 0 43 33 53 19 32 52 55 112 -16 42 16 39 44 51 33 41 32 3 45 36 50 151 0 0 43 33 53 19 32 54 56 113 -16 42 16 40 44 51 33 41 32 4 45 36 50 152 0 0 43 33 30 19 32 57 57 115 -15 42 16 16 44 51 11 41 31 40 45 36 27 153 0 0 43 32 44 19 33 0 57 116 -14 42 15 29 44 50 25 41 30 53 45 35 42 154 0 0 43 31 34 19 33 3 58 117 -13 42 14 19 44 49 17 41 29 42 45 34 35 155 0 0 43 30 2 19 33 5 59 118 -13 42 12 45 44 47 46 41 28 7 45 33 4 156 0 0 43 28 6 19 33 8 59 119 -12 42 10 48 44 45 52 41 26 9 45 31 11 157 0 0 43 25 47 19 33 11 60 121 -11 42 8 27 44 43 35 41 23 46 45 28 56 158 0 0 43 23 5 19 33 14 61 122 -11 42 5 42 44 40 55 41 21 0 45 26 18 159 0 0 43 19 59 19 33 17 61 123 -10 42 2 33 44 37 53 41 17 50 45 23 17 160 0 0 43 16 31 19 33 20 62 125 -9 41 59 1 44 34 27 41 14 16 45 19 53 161 0 0 43 12 38 19 33 23 63 126 -8 41 55 5 44 30 38 41 10 18 45 16 6 162 0 0 43 8 22 19 33 26 63 128 -8 41 50 46 44 26 27 41 5 56 45 11 57 163 0 0 43 3 43 19 33 29 64 129 -7 41 46 2 44 21 51 41 1 10 45 7 25 164 0 0 42 58 40 19 33 32 64 131 -6 41 40 54 44 16 53 40 56 0 45 2 29 165 0 0 42 53 13 19 33 35 65 132 -6 41 35 23 44 11 32 40 50 25 44 57 10 166 0 0 42 47 23 19 33 38 66 134 -5 41 29 27 44 5 47 40 44 26 44 51 29 167 0 0 42 41 8 19 33 41 66 136 -4 41 23 7 43 59 38 40 38 3 44 45 24 168 0 0 42 34 30 19 33 44 67 137 -3 41 16 22 43 53 6 40 31 15 44 38 55 169 0 0 42 27 28 19 33 47 67 139 -3 41 9 14 43 46 10 40 24 3 44 32 3 170 0 0 42 20 1 19 33 50 68 141 -2 41 1 41 43 38 51 40 16 26 44 24 47 171 0 0 42 12 11 19 33 53 69 143 -1 40 53 43 43 31 7 40 8 24 44 17 8 172 0 0 42 3 56 19 33 56 69 145 -1 40 45 20 43 23 0 39 59 57 44 9 5 Uncertainty in time = +/- 3 secs Prediction of 2012 Nov 16.0 Data for the target star ------------------------ * name: TYC 1986-00436-1 * constellation : Coma Berenices * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 12 04 58.2667 DE: +24 13 17.616 * position source: mpos:UCAC4 pm:UCAC4 * standard error: RA,DE ["]: ( .019, .040 ) * V mag [mag]: 11.0 * B mag [mag]: 11.7 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (31) Euphrosyne approx. diameter [km]: 277 approx. diameter ["]: .138 distance from Earth [AU]: 2.77400 * orbital information: orbit source: Preston date of fit: 2012 Oct 25 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1156 number of rejected observations: 87 time covered by the observations: 1907 Apr 10 - 2012 Mar 15 1 sigma uncertainty ellipse (major, minor, PA): 0.013, 0.010, 141° remarks: * orbital elements for (31) Euphrosyne : Mean anomaly = 34.95643673 deg Arg. of pericenter = 61.25959628 deg Long. of node = 31.15093623 deg Inclination = 26.31725157 deg Eccentricity = 0.22231825 Semimajor axis = 3.15313474 AU Perihelion dist = 2.45213533 AU Mag: H = 6.76, G = 0.15 Epoch of elements : MJD 56254.81600000 TDT (2012 Nov 23.816) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Nov 23 31 Euphrosyne 19h 34.9m UT 11.0 12 4 58.267 24 13 17.62TYC 1986-00436-1 11.7 12.1 277 10.7 2.774 3.261 -12.54 -175.6627 24.225 -117.07 -20.55 19.5821 0.06743 0.24641 14.07328 -3.95811 -0.00467 0.00304 2000 34.10867020121119.00000 61.259596 31.150936 26.3172520.22231825 3.1531347 2.4521353 6.7 5.00.15 RATE 1.7603140 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.042 0.021 177 1.29 0.040 0 0-3-4 056247.0020121123_0436-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Oct 25, 21:52 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org