IOTA/IOTA-ES occultation update for (404) Arsinoe / TYC 7407-00681-1 event on 2012 Aug 03, 06:47 UT Visible from W USA, SW Canada Summary ------- On 2012 Aug 03 UT, the 117 km diameter asteroid (404) Arsinoe will occult a 12.2 mag star in the constellation Sagittarius for observers along a path across W USA, SW Canada. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.9 mag to 12.5 mag (the magnitude of the asteroid) for at most 19.7 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: 97 * date and approx. time of event: 2012 Aug 03, 06:35 - 2012 Aug 03, 06:57 UT * geocentric midpoint of event [JD]: 2456142.783375 * magnitude of target star: 12.2 * magnitude drop [mag]: 0.9 * estimated maximum duration [s]: 19.7 * Moon: 98 % sunlit, 50° distance * Sun: 146° distance * rough path description: W USA, SW Canada The occultation path -------------------- * approximate projected width [km]: 170 * 1 sigma uncertainty interval [path widths]: +/- 0.40 * 1 sigma uncertainty interval [seconds]: +/- 8.6 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .057 +/- .038) * 1 sigma uncertainty ellipse (major, minor, PA): ( .057", .038", 92° ) * approx speed of asteroid's shadow [km/s]: 5.9258 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 7407-00681-1 by 404 Arsinoe on 2012 Aug 3 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 -109 55 56 57 0 0 6 35 47 1 198 -15 -111 27 44 -108 24 58 -112 41 48 ... .. .. -110 33 22 56 0 0 6 35 48 2 198 -16 -112 3 11 -109 4 21 -113 15 41 ... .. .. -111 11 13 55 0 0 6 35 49 3 197 -17 -112 39 13 -109 44 1 -113 50 15 -108 34 47 -111 49 30 54 0 0 6 35 50 4 197 -18 -113 15 49 -110 24 0 -114 25 29 -109 16 7 -112 28 16 53 0 0 6 35 53 5 196 -19 -113 53 0 -111 4 19 -115 1 25 -109 57 41 -113 7 30 52 0 0 6 35 55 6 196 -19 -114 30 47 -111 45 1 -115 38 2 -110 39 33 -113 47 15 51 0 0 6 35 58 7 195 -20 -115 9 11 -112 26 6 -116 15 21 -111 21 43 -114 27 32 50 0 0 6 36 2 8 195 -21 -115 48 13 -113 7 38 -116 53 22 -112 4 14 -115 8 21 49 0 0 6 36 7 9 194 -22 -116 27 53 -113 49 36 -117 32 7 -112 47 8 -115 49 44 48 0 0 6 36 12 10 194 -23 -117 8 12 -114 32 4 -118 11 35 -113 30 28 -116 31 44 47 0 0 6 36 17 11 193 -24 -117 49 13 -115 15 2 -118 51 49 -114 14 13 -117 14 20 46 0 0 6 36 23 12 192 -24 -118 30 55 -115 58 33 -119 32 48 -114 58 28 -117 57 36 45 0 0 6 36 30 13 192 -25 -119 13 21 -116 42 39 -120 14 35 -115 43 13 -118 41 32 44 0 0 6 36 37 15 191 -26 -119 56 32 -117 27 20 -120 57 9 -116 28 31 -119 26 9 43 0 0 6 36 45 16 191 -27 -120 40 29 -118 12 39 -121 40 34 -117 14 24 -120 11 31 42 0 0 6 36 54 17 190 -27 -121 25 14 -118 58 38 -122 24 50 -118 0 53 -120 57 38 41 0 0 6 37 3 18 190 -28 -122 10 49 -119 45 19 -123 9 59 -118 48 1 -121 44 34 40 0 0 6 37 12 19 189 -29 -122 57 15 -120 32 43 -123 56 3 -119 35 49 -122 32 19 39 0 0 6 37 23 20 188 -29 -123 44 35 -121 20 54 -124 43 4 -120 24 21 -123 20 56 38 0 0 6 37 34 21 188 -30 -124 32 51 -122 9 53 -125 31 4 -121 13 38 -124 10 27 37 0 0 6 37 45 22 187 -30 -125 22 6 -122 59 43 -126 20 6 -122 3 43 -125 0 56 36 0 0 6 37 58 23 186 -31 -126 12 21 -123 50 26 -127 10 11 -122 54 39 -125 52 24 35 0 0 6 38 11 24 186 -31 -127 3 40 -124 42 5 -128 1 24 -123 46 28 -126 44 56 34 0 0 6 38 24 25 185 -32 -127 56 5 -125 34 43 -128 53 46 -124 39 13 -127 38 32 33 0 0 6 38 39 26 184 -32 -128 49 41 -126 28 24 -129 47 21 -125 32 57 -128 33 19 32 0 0 6 38 54 27 183 -33 -129 44 29 -127 23 9 -130 42 13 -126 27 43 -129 29 18 31 0 0 6 39 10 28 183 -33 -130 40 35 -128 19 4 -131 38 25 -127 23 35 -130 26 34 30 0 0 6 39 26 29 182 -34 -131 38 2 -129 16 11 -132 36 2 -128 20 37 -131 25 11 29 0 0 6 39 43 30 181 -34 -132 36 55 -130 14 35 -133 35 9 -129 18 52 -132 25 14 28 0 0 6 40 1 31 180 -34 -133 37 18 -131 14 21 -134 35 51 -130 18 25 -133 26 49 27 0 0 6 40 20 32 179 -34 -134 39 18 -132 15 33 -135 38 14 -131 19 22 -134 30 0 26 0 0 6 40 39 33 178 -34 -135 43 0 -133 18 17 -136 42 24 -132 21 46 -135 34 55 25 0 0 6 41 0 34 177 -35 -136 48 32 -134 22 38 -137 48 28 -133 25 43 -136 41 40 24 0 0 6 41 21 35 176 -35 -137 56 1 -135 28 44 -138 56 35 -134 31 21 -137 50 24 23 0 0 6 41 43 36 175 -35 -139 5 35 -136 36 42 -140 6 54 -135 38 46 -139 1 14 22 0 0 6 42 6 37 173 -35 -140 17 24 -137 46 40 -141 19 34 -136 48 5 -140 14 22 21 0 0 6 42 30 38 172 -34 -141 31 39 -138 58 48 -142 34 48 -137 59 28 -141 29 59 20 0 0 6 42 55 39 171 -34 -142 48 33 -140 13 15 -143 52 50 -139 13 4 -142 48 18 19 0 0 6 43 20 40 169 -34 -144 8 20 -141 30 13 -145 13 55 -140 29 4 -144 9 33 18 0 0 6 43 47 40 168 -34 -145 31 17 -142 49 57 -146 38 22 -141 47 41 -145 34 4 17 0 0 6 44 15 41 166 -33 -146 57 45 -144 12 43 -148 6 34 -143 9 10 -147 2 10 16 0 0 6 44 45 42 164 -33 -148 28 7 -145 38 48 -149 38 56 -144 33 47 -148 34 17 15 0 0 6 45 15 42 163 -32 -150 2 51 -147 8 35 -151 16 1 -146 1 53 -150 10 55 14 0 0 6 45 47 43 161 -31 -151 42 34 -148 42 30 -152 58 31 -147 33 51 -151 52 42 13 0 0 6 46 21 43 159 -31 -153 28 0 -150 21 6 -154 47 15 -149 10 10 -153 40 25 12 0 0 6 46 56 43 157 -30 -155 20 5 -152 5 2 -156 43 22 -150 51 26 -155 35 4 11 0 0 6 47 33 44 154 -29 -157 20 4 -153 55 8 -158 48 22 -152 38 21 -157 38 1 10 0 0 6 48 13 44 152 -27 -159 29 41 -155 52 31 -161 4 21 -154 31 52 Latitude Latitude Latitude Latitude -159 0 0 9 22 27 6 48 39 44 151 -26 10 13 18 8 32 26 10 54 39 7 53 0 -160 0 0 8 56 11 6 48 58 43 149 -26 9 46 41 8 6 31 10 27 43 7 27 21 -161 0 0 8 30 56 6 49 17 43 148 -25 9 21 5 7 41 37 10 1 50 7 2 42 -162 0 0 8 6 43 6 49 35 43 147 -24 8 56 32 7 17 42 9 37 0 6 39 2 -163 0 0 7 43 30 6 49 54 43 146 -24 8 33 0 6 54 46 9 13 12 6 16 20 -164 0 0 7 21 16 6 50 12 43 145 -23 8 10 29 6 32 50 8 50 26 5 54 36 -165 0 0 7 0 2 6 50 30 43 144 -22 7 48 58 6 11 51 8 28 41 5 33 50 -166 0 0 6 39 46 6 50 48 42 143 -22 7 28 27 5 51 51 8 7 57 5 14 1 -167 0 0 6 20 30 6 51 6 42 142 -21 7 8 55 5 32 48 7 48 13 4 55 9 -168 0 0 6 2 11 6 51 23 42 141 -20 6 50 22 5 14 43 7 29 28 4 37 14 -169 0 0 5 44 49 6 51 41 41 141 -19 6 32 48 4 57 34 7 11 43 4 20 15 -170 0 0 5 28 25 6 51 58 41 140 -19 6 16 12 4 41 22 6 54 57 4 4 11 -171 0 0 5 12 59 6 52 15 41 139 -18 6 0 33 4 26 6 6 39 9 3 49 4 -172 0 0 4 58 28 6 52 32 40 138 -17 5 45 53 4 11 45 6 24 20 3 34 51 -173 0 0 4 44 55 6 52 49 40 137 -16 5 32 9 3 58 21 6 10 28 3 21 34 -174 0 0 4 32 17 6 53 5 39 136 -15 5 19 23 3 45 52 5 57 34 3 9 11 -175 0 0 4 20 35 6 53 21 39 136 -15 5 7 33 3 34 18 5 45 38 2 57 43 -176 0 0 4 9 50 6 53 37 38 135 -14 4 56 40 3 23 39 5 34 39 2 47 10 -177 0 0 3 59 59 6 53 53 38 134 -13 4 46 44 3 13 55 5 24 37 2 37 30 -178 0 0 3 51 5 6 54 9 37 134 -12 4 37 43 3 5 6 5 15 32 2 28 46 -179 0 0 3 43 6 6 54 24 36 133 -11 4 29 39 2 57 11 5 7 24 2 20 55 -180 0 0 3 36 2 6 54 39 36 133 -10 4 22 31 2 50 12 5 0 12 2 13 58 179 0 0 3 29 53 6 54 54 35 132 -10 4 16 20 2 44 6 4 53 58 2 7 55 178 0 0 3 24 40 6 55 9 35 131 -9 4 11 4 2 38 56 4 48 40 2 2 47 177 0 0 3 20 23 6 55 23 34 131 -8 4 6 44 2 34 40 4 44 19 1 58 32 176 0 0 3 17 0 6 55 37 33 130 -7 4 3 21 2 31 19 4 40 54 1 55 12 175 0 0 3 14 33 6 55 51 33 130 -6 4 0 53 2 28 52 4 38 27 1 52 46 174 0 0 3 13 2 6 56 5 32 130 -5 3 59 23 2 27 21 4 36 56 1 51 14 173 0 0 3 12 27 6 56 18 31 129 -4 3 58 48 2 26 44 4 36 23 1 50 36 172 0 0 3 12 47 6 56 32 30 129 -3 3 59 11 2 27 3 4 36 47 1 50 54 171 0 0 3 14 4 6 56 44 30 128 -3 4 0 30 2 28 17 4 38 9 1 52 6 170 0 0 3 16 17 6 56 57 29 128 -2 4 2 46 2 30 26 4 40 28 1 54 13 169 0 0 3 19 26 6 57 9 28 128 -1 4 6 0 2 33 32 4 43 46 1 57 15 Uncertainty in time = +/- 10 secs Prediction of 2012 Jul 21.0 Data for the target star ------------------------ * name: TYC 7407-00681-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 18 38 53.1524 DE: -30 44 36.088 * position source: mpos:UCAC4 pm:UCAC4 * standard error: RA,DE ["]: ( .052, .035 ) * V mag [mag]: 12.2 * B mag [mag]: 12.6 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (404) Arsinoe approx. diameter [km]: 117 approx. diameter ["]: .109 distance from Earth [AU]: 1.48600 * orbital information: orbit source: Preston date of fit: 2012 Jul 21 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 1114 number of rejected observations: 50 time covered by the observations: 1909 Nov 06 - 2012 Jul 10 1 sigma uncertainty ellipse (major, minor, PA): 0.025, 0.013, 100° remarks: * orbital elements for (404) Arsinoe : Mean anomaly = 57.22606237 deg Arg. of pericenter = 120.70641711 deg Long. of node = 92.64065521 deg Inclination = 14.11186332 deg Eccentricity = 0.19956415 Semimajor axis = 2.59363679 AU Perihelion dist = 2.07603988 AU Mag: H = 9.07, G = 0.15 Epoch of elements : MJD 56142.28300000 TDT (2012 Aug 03.283) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Aug 3 404 Arsinoe 6h 48.1m UT 12.2 18 38 53.152-30 44 36.09TYC 7407-00681-1 12.6 12.5 117 19.7 1.486 -1.301 -10.48 -134.5509 -30.739 79.53 17.37 6.8010 -0.38166 0.61519 -2.83666 -1.77212 0.00285 0.00079 2000 56.6873632012 8 1.00000120.706417 92.640655 14.1118630.19956415 2.5936368 2.0760399 9.0 5.00.15 RATE 2.3596100 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.057 0.038 92 1.40 0.043 0 0 4 2 056129.0020120803_0681-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Jul 21, 14:03 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org