IOTA/IOTA-ES occultation update for (1585) Union / TYC 5783-01366-1 event on 2012 Sep 10, 07:01 UT Visible from W Canada, Alaska Summary ------- On 2012 Sep 10 UT, the 51 km diameter asteroid (1585) Union will occult a 11.4 mag star in the constellation Aquarius for observers along a path across W Canada, Alaska. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.4 mag to 14.7 mag (the magnitude of the asteroid) for at most 4.0 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, TMO astrometry for the asteroid kindly provided by Bill Owen, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 66 * date and approx. time of event: 2012 Sep 10, 06:53 - 2012 Sep 10, 07:06 UT * geocentric midpoint of event [JD]: 2456180.7925 * magnitude of target star: 11.4 * magnitude drop [mag]: 3.4 * estimated maximum duration [s]: 4.0 * Moon: 34 % sunlit, 142° distance * Sun: 147° distance * rough path description: W Canada, Alaska The occultation path -------------------- * approximate projected width [km]: 58 * 1 sigma uncertainty interval [path widths]: +/- 0.91 * 1 sigma uncertainty interval [seconds]: +/- 4.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .035 +/- .044) * 1 sigma uncertainty ellipse (major, minor, PA): ( .044", .035", 1° ) * approx speed of asteroid's shadow [km/s]: 12.8033 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5783-01366-1 by 1585 Union on 2012 Sep 10 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 -125 30 54 75 0 0 6 53 54 1 191 -9 -126 32 19 -124 29 25 -128 24 3 -122 37 20 -126 15 1 74 0 0 6 53 54 2 190 -10 -127 12 41 -125 17 18 -128 57 37 -123 32 8 -126 56 3 73 0 0 6 53 55 3 189 -11 -127 50 25 -126 1 39 -129 29 23 -124 22 33 -127 34 32 72 0 0 6 53 55 4 189 -12 -128 26 0 -126 43 4 -129 59 40 -125 9 20 -128 10 54 71 0 0 6 53 56 5 188 -13 -128 59 46 -127 22 2 -130 28 43 -125 53 5 -128 45 29 70 0 0 6 53 57 6 188 -14 -129 32 1 -127 58 57 -130 56 44 -126 34 16 -129 18 33 69 0 0 6 53 58 7 187 -14 -130 2 59 -128 34 8 -131 23 54 -127 13 17 -129 50 20 68 0 0 6 53 59 8 187 -15 -130 32 52 -129 7 49 -131 50 20 -127 50 27 -130 21 1 67 0 0 6 54 1 9 186 -16 -131 1 49 -129 40 14 -132 16 9 -128 26 2 -130 50 45 66 0 0 6 54 2 10 186 -17 -131 29 59 -130 11 33 -132 41 27 -129 0 14 -131 19 41 65 0 0 6 54 4 11 185 -18 -131 57 28 -130 41 55 -133 6 18 -129 33 15 -131 47 54 64 0 0 6 54 6 12 185 -18 -132 24 22 -131 11 29 -133 30 47 -130 5 13 -132 15 32 63 0 0 6 54 8 13 184 -19 -132 50 45 -131 40 19 -133 54 57 -130 36 18 -132 42 37 62 0 0 6 54 11 14 184 -20 -133 16 43 -132 8 33 -134 18 52 -131 6 35 -133 9 16 61 0 0 6 54 13 15 184 -21 -133 42 19 -132 36 14 -134 42 34 -131 36 11 -133 35 31 60 0 0 6 54 16 16 183 -21 -134 7 36 -133 3 28 -135 6 4 -132 5 11 -134 1 26 59 0 0 6 54 19 17 183 -22 -134 32 37 -133 30 17 -135 29 27 -132 33 39 -134 27 4 58 0 0 6 54 22 18 182 -23 -134 57 24 -133 56 45 -135 52 42 -133 1 40 -134 52 27 57 0 0 6 54 25 19 182 -24 -135 22 0 -134 22 56 -136 15 52 -133 29 16 -135 17 38 56 0 0 6 54 28 20 182 -24 -135 46 27 -134 48 51 -136 38 59 -133 56 32 -135 42 39 55 0 0 6 54 32 21 181 -25 -136 10 47 -135 14 33 -137 2 4 -134 23 29 -136 7 32 54 0 0 6 54 36 22 181 -26 -136 35 1 -135 40 5 -137 25 7 -134 50 11 -136 32 18 53 0 0 6 54 39 23 180 -26 -136 59 11 -136 5 27 -137 48 11 -135 16 39 -136 56 59 52 0 0 6 54 44 24 180 -27 -137 23 17 -136 30 42 -138 11 15 -135 42 57 -137 21 36 51 0 0 6 54 48 25 179 -28 -137 47 23 -136 55 52 -138 34 22 -136 9 5 -137 46 12 50 0 0 6 54 52 26 179 -28 -138 11 28 -137 20 57 -138 57 32 -136 35 5 -138 10 46 49 0 0 6 54 57 27 179 -29 -138 35 34 -137 46 0 -139 20 46 -137 1 0 -138 35 20 48 0 0 6 55 1 28 178 -29 -138 59 41 -138 11 1 -139 44 5 -137 26 50 -138 59 56 47 0 0 6 55 6 29 178 -30 -139 23 52 -138 36 2 -140 7 29 -137 52 37 -139 24 34 46 0 0 6 55 11 30 177 -31 -139 48 6 -139 1 4 -140 31 0 -138 18 23 -139 49 15 45 0 0 6 55 16 31 177 -31 -140 12 24 -139 26 8 -140 54 38 -138 44 8 -140 14 1 44 0 0 6 55 22 32 176 -32 -140 36 49 -139 51 15 -141 18 23 -139 9 53 -140 38 51 43 0 0 6 55 27 33 176 -32 -141 1 19 -140 16 25 -141 42 17 -139 35 40 -141 3 48 42 0 0 6 55 33 34 175 -33 -141 25 56 -140 41 41 -142 6 20 -140 1 30 -141 28 51 41 0 0 6 55 39 35 175 -33 -141 50 41 -141 7 2 -142 30 32 -140 27 24 -141 54 1 40 0 0 6 55 45 36 174 -34 -142 15 35 -141 32 29 -142 54 55 -140 53 23 -142 19 20 39 0 0 6 55 51 37 174 -34 -142 40 38 -141 58 4 -143 19 29 -141 19 27 -142 44 48 38 0 0 6 55 57 38 173 -35 -143 5 51 -142 23 47 -143 44 14 -141 45 37 -143 10 26 37 0 0 6 56 3 39 173 -35 -143 31 14 -142 49 39 -144 9 12 -142 11 55 -143 36 14 36 0 0 6 56 10 40 172 -35 -143 56 49 -143 15 41 -144 34 22 -142 38 22 -144 2 14 35 0 0 6 56 17 41 171 -36 -144 22 36 -143 41 53 -144 59 46 -143 4 57 -144 28 25 34 0 0 6 56 23 42 171 -36 -144 48 36 -144 8 17 -145 25 25 -143 31 42 -144 54 50 33 0 0 6 56 30 43 170 -37 -145 14 49 -144 34 52 -145 51 17 -143 58 38 -145 21 28 32 0 0 6 56 37 44 169 -37 -145 41 17 -145 1 41 -146 17 26 -144 25 45 -145 48 20 31 0 0 6 56 45 44 168 -37 -146 7 59 -145 28 42 -146 43 50 -144 53 5 -146 15 27 30 0 0 6 56 52 45 168 -37 -146 34 57 -145 55 58 -147 10 31 -145 20 38 -146 42 49 29 0 0 6 56 59 46 167 -38 -147 2 11 -146 23 30 -147 37 30 -145 48 24 -147 10 28 28 0 0 6 57 7 47 166 -38 -147 29 42 -146 51 17 -148 4 47 -146 16 26 -147 38 25 27 0 0 6 57 15 48 165 -38 -147 57 31 -147 19 20 -148 32 23 -146 44 43 -148 6 39 26 0 0 6 57 23 49 164 -38 -148 25 39 -147 47 41 -149 0 18 -147 13 16 -148 35 12 25 0 0 6 57 31 50 163 -38 -148 54 6 -148 16 21 -149 28 34 -147 42 7 -149 4 5 24 0 0 6 57 39 50 162 -39 -149 22 53 -148 45 19 -149 57 12 -148 11 16 -149 33 19 23 0 0 6 57 47 51 161 -39 -149 52 1 -149 14 38 -150 26 11 -148 40 44 -150 2 54 22 0 0 6 57 55 52 160 -39 -150 21 32 -149 44 18 -150 55 33 -149 10 32 -150 32 51 21 0 0 6 58 4 53 159 -39 -150 51 25 -150 14 19 -151 25 19 -149 40 41 -151 3 12 20 0 0 6 58 12 54 158 -39 -151 21 43 -150 44 43 -151 55 30 -150 11 12 -151 33 57 19 0 0 6 58 21 54 157 -39 -151 52 25 -151 15 31 -152 26 7 -150 42 5 -152 5 7 18 0 0 6 58 30 55 155 -39 -152 23 33 -151 46 44 -152 57 11 -151 13 23 -152 36 44 17 0 0 6 58 39 56 154 -39 -152 55 8 -152 18 23 -153 28 43 -151 45 5 -153 8 49 16 0 0 6 58 48 57 152 -38 -153 27 11 -152 50 29 -154 0 43 -152 17 14 -153 41 22 15 0 0 6 58 57 57 151 -38 -153 59 43 -153 23 3 -154 33 14 -152 49 50 -154 14 25 14 0 0 6 59 6 58 149 -38 -154 32 46 -153 56 7 -155 6 17 -153 22 54 -154 48 0 13 0 0 6 59 15 58 148 -38 -155 6 21 -154 29 41 -155 39 52 -153 56 29 -155 22 7 12 0 0 6 59 25 59 146 -38 -155 40 29 -155 3 48 -156 14 1 -154 30 34 -155 56 48 11 0 0 6 59 34 59 144 -38 -156 15 11 -155 38 28 -156 48 46 -155 5 12 -156 32 5 10 0 0 6 59 44 60 142 -37 -156 50 30 -156 13 43 -157 24 8 -155 40 25 -157 7 59 9 0 0 6 59 54 60 140 -37 -157 26 26 -156 49 35 -158 0 9 -156 16 12 -157 44 32 8 0 0 7 0 3 61 138 -37 -158 3 2 -157 26 5 -158 36 51 -156 52 38 -158 21 46 7 0 0 7 0 13 61 136 -36 -158 40 19 -158 3 15 -159 14 15 -157 29 42 -158 59 42 6 0 0 7 0 23 61 134 -36 -159 18 20 -158 41 7 -159 52 23 -158 7 27 -159 38 23 5 0 0 7 0 33 62 132 -35 -159 57 6 -159 19 43 -160 31 18 -158 45 55 -160 17 50 4 0 0 7 0 43 62 130 -35 -160 36 39 -159 59 6 -161 11 1 -159 25 7 -160 58 7 3 0 0 7 0 54 62 128 -35 -161 17 2 -160 39 16 -161 51 36 -160 5 7 -161 39 16 2 0 0 7 1 4 62 125 -34 -161 58 17 -161 20 18 -162 33 4 -160 45 57 -162 21 18 1 0 0 7 1 14 62 123 -33 -162 40 27 -162 2 13 -163 15 29 -161 27 39 -163 4 18 0 0 0 7 1 25 62 121 -33 -163 23 35 -162 45 4 -163 58 53 -162 10 15 -163 48 18 - 1 0 0 7 1 35 62 119 -32 -164 7 44 -163 28 55 -164 43 19 -162 53 49 Latitude Latitude Latitude Latitude -165 0 0 - 2 34 49 7 1 52 62 115 -31 - 2 9 12 - 3 0 17 - 1 22 9 - 3 46 12 -166 0 0 - 3 51 24 7 2 6 61 112 -30 - 3 26 17 - 4 16 22 - 2 40 10 - 5 1 25 -167 0 0 - 5 5 31 7 2 19 61 110 -30 - 4 40 53 - 5 30 1 - 3 55 40 - 6 14 14 -168 0 0 - 6 17 15 7 2 32 60 107 -29 - 5 53 4 - 6 41 17 - 5 8 42 - 7 24 43 -169 0 0 - 7 26 38 7 2 45 60 105 -28 - 7 2 53 - 7 50 15 - 6 19 20 - 8 32 55 -170 0 0 - 8 33 45 7 2 57 59 103 -27 - 8 10 25 - 8 56 58 - 7 27 38 - 9 38 54 -171 0 0 - 9 38 39 7 3 9 58 101 -26 - 9 15 43 -10 1 28 - 8 33 40 -10 42 43 -172 0 0 -10 41 24 7 3 21 58 99 -25 -10 18 50 -11 3 51 - 9 37 29 -11 44 26 -173 0 0 -11 42 2 7 3 32 57 98 -24 -11 19 50 -12 4 8 -10 39 10 -12 44 5 -174 0 0 -12 40 38 7 3 43 56 96 -23 -12 18 47 -13 2 24 -11 38 45 -13 41 44 -175 0 0 -13 37 15 7 3 54 55 95 -22 -13 15 43 -13 58 41 -12 36 18 -14 37 27 -176 0 0 -14 31 55 7 4 4 54 94 -21 -14 10 43 -14 53 2 -13 31 52 -15 31 15 -177 0 0 -15 24 43 7 4 14 53 93 -20 -15 3 48 -15 45 32 -14 25 31 -16 23 13 -178 0 0 -16 15 40 7 4 24 53 92 -19 -15 55 3 -16 36 13 -15 17 18 -17 13 23 -179 0 0 -17 4 51 7 4 34 52 91 -18 -16 44 30 -17 25 7 -16 7 16 -18 1 48 -180 0 0 -17 52 17 7 4 43 51 90 -18 -17 32 13 -18 12 18 -16 55 27 -18 48 31 179 0 0 -18 38 3 7 4 52 50 90 -17 -18 18 13 -18 57 48 -17 41 56 -19 33 34 178 0 0 -19 22 10 7 5 1 49 89 -16 -19 2 34 -19 41 40 -18 26 44 -20 17 1 177 0 0 -20 4 40 7 5 9 48 89 -15 -19 45 19 -20 23 58 -19 9 55 -20 58 53 176 0 0 -20 45 38 7 5 17 47 88 -14 -20 26 30 -21 4 42 -19 51 30 -21 39 14 175 0 0 -21 25 4 7 5 25 46 88 -13 -21 6 9 -21 43 56 -20 31 33 -22 18 5 174 0 0 -22 3 3 7 5 33 45 88 -12 -21 44 20 -22 21 42 -21 10 6 -22 55 29 173 0 0 -22 39 34 7 5 41 44 88 -11 -22 21 3 -22 58 2 -21 47 11 -23 31 29 172 0 0 -23 14 42 7 5 48 43 88 -10 -22 56 22 -23 32 59 -22 22 50 -24 6 5 171 0 0 -23 48 28 7 5 55 42 87 -9 -23 30 18 -24 6 34 -22 57 6 -24 39 22 170 0 0 -24 20 53 7 6 2 42 87 -9 -24 2 54 -24 38 49 -23 30 1 -25 11 19 169 0 0 -24 52 1 7 6 8 41 87 -8 -24 34 11 -25 9 47 -24 1 37 -25 41 59 168 0 0 -25 21 52 7 6 15 40 87 -7 -25 4 12 -25 39 29 -24 31 55 -26 11 25 167 0 0 -25 50 29 7 6 21 39 87 -6 -25 32 58 -26 7 57 -25 0 57 -26 39 37 166 0 0 -26 17 54 7 6 27 38 88 -5 -26 0 31 -26 35 13 -25 28 45 -27 6 38 165 0 0 -26 44 7 7 6 33 37 88 -4 -26 26 52 -27 1 18 -25 55 22 -27 32 29 164 0 0 -27 9 11 7 6 39 36 88 -3 -26 52 4 -27 26 14 -26 20 47 -27 57 11 163 0 0 -27 33 6 7 6 44 35 88 -3 -27 16 7 -27 50 3 -26 45 4 -28 20 46 162 0 0 -27 55 55 7 6 49 34 88 -2 -27 39 3 -28 12 45 -27 8 12 -28 43 15 161 0 0 -28 17 39 7 6 54 34 88 -1 -28 0 53 -28 34 22 -27 30 15 -29 4 41 160 0 0 -28 38 18 7 6 59 33 89 0 -28 21 38 -28 54 55 -27 51 12 -29 25 2 Uncertainty in time = +/- 4 secs Prediction of 2012 Sep 8.0 Data for the target star ------------------------ * name: TYC 5783-01366-1 * constellation : Aquarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 21 05 29.3269 DE: -14 01 51.066 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .024, .041 ) * V mag [mag]: 11.4 * B mag [mag]: 11.8 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1585) Union approx. diameter [km]: 51 approx. diameter ["]: .041 distance from Earth [AU]: 1.72700 * orbital information: orbit source: Preston date of fit: 2012 Sep 07 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 1008 number of rejected observations: 61 time covered by the observations: 1939 Feb 13 - 2012 Sep 01 1 sigma uncertainty ellipse (major, minor, PA): 0.025, 0.015, 101° remarks: * orbital elements for (1585) Union : Mean anomaly = 306.06891483 deg Arg. of pericenter = 264.79528237 deg Long. of node = 150.11656333 deg Inclination = 26.17430402 deg Eccentricity = 0.30885679 Semimajor axis = 2.92849784 AU Perihelion dist = 2.02401141 AU Mag: H = 10.21, G = 0.15 Epoch of elements : MJD 56180.29300000 TDT (2012 Sep 10.293) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 10 1585 Union 7h 1.2m UT 11.4 21 5 29.327-14 1 51.07TYC 5783-01366-1 11.8 14.7 51 4.0 1.727 -1.300 -31.53 -138.6488 -14.022 73.93 4.75 7.0200 -0.40243 0.24152 -3.71847 -6.19641 0.00298 0.00068 2000 306.0112912012 910.00000264.795282150.116563 26.1743040.30885679 2.9284978 2.024011410.7 5.00.15 RATE 1.9666940 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.044 0.035 1 1.91 0.037 0 0-1 4 056178.0020120910_1366-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Sep 07, 22:41 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org