IOTA/IOTA-ES occultation update for (792) Metcalfia / 2UCAC 22924840 event on 2009 Mar 30, 11:44 UT Visible from W USA Summary ------- On 2009 Mar 30 UT, the 61 km diameter asteroid (792) Metcalfia will occult a 12.4 mag star in the constellation Virgo for observers along a path across W USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.6 mag to 13.7 mag (the magnitude of the asteroid) for at most 6.5 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: 88 * date and approx. time of event: 2009 Mar 30, 11:40 - 2009 Mar 30, 11:48 UT * magnitude of target star: 12.4 * magnitude drop [mag]: 1.6 * estimated maximum duration [s]: 6.5 * Moon: 17 % sunlit, 147° distance * Sun: 159° distance * rough path description: W USA Additional comments ------------------- low altitude The occultation path -------------------- * approximate projected width [km]: 159 * 1 sigma uncertainty interval [path widths]: +/- 0.55 * 1 sigma uncertainty interval [seconds]: +/- 4.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .045 +/- .031) * 1 sigma uncertainty ellipse (major, minor, PA): ( .046", .030", 102° ) * approx speed of asteroid's shadow [km/s]: 9.3252 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 22924840 by 792 Metcalfia on 2009 Mar 30 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 -166 10 39 67 0 0 11 48 56 1 179 -19 -164 15 36 -168 2 18 -162 4 34 ... .. .. -166 1 27 66 0 0 11 48 56 2 179 -20 -164 10 38 -167 49 6 -162 4 34 ... .. .. -165 46 40 65 0 0 11 48 54 3 180 -21 -163 59 33 -167 30 47 -161 57 49 ... .. .. -165 26 49 64 0 0 11 48 53 4 180 -22 -163 42 56 -167 7 50 -161 44 59 -168 56 2 -165 2 18 63 0 0 11 48 50 5 180 -23 -163 21 17 -166 40 36 -161 26 37 -168 25 54 -164 33 29 62 0 0 11 48 47 6 181 -24 -162 54 57 -166 9 22 -161 3 10 -167 52 8 -164 0 36 61 0 0 11 48 44 7 181 -24 -162 24 15 -165 34 24 -160 34 56 -167 14 55 -163 23 54 60 0 0 11 48 40 8 182 -25 -161 49 25 -164 55 52 -160 2 14 -166 34 25 -162 43 30 59 0 0 11 48 35 9 182 -26 -161 10 38 -164 13 54 -159 25 15 -165 50 45 -161 59 33 58 0 0 11 48 30 10 183 -27 -160 28 1 -163 28 37 -158 44 8 -165 4 1 -161 12 6 57 0 0 11 48 24 11 184 -28 -159 41 39 -162 40 4 -157 58 58 -164 14 16 -160 21 11 56 0 0 11 48 17 12 185 -29 -158 51 36 -161 48 17 -157 9 49 -163 21 30 -159 26 48 55 0 0 11 48 10 13 185 -30 -157 57 50 -160 53 15 -156 16 41 -162 25 43 -158 28 55 54 0 0 11 48 2 14 186 -30 -157 0 19 -159 54 56 -155 19 29 -161 26 52 -157 27 27 53 0 0 11 47 53 14 187 -31 -155 58 58 -158 53 16 -154 18 9 -160 24 55 -156 22 17 52 0 0 11 47 44 15 188 -32 -154 53 39 -157 48 8 -153 12 31 -159 19 43 -155 13 13 51 0 0 11 47 33 16 189 -32 -153 44 9 -156 39 23 -152 2 21 -158 11 10 -154 0 4 50 0 0 11 47 22 17 191 -33 -152 30 14 -155 26 48 -150 47 22 -156 59 4 -152 42 30 49 0 0 11 47 10 18 192 -34 -151 11 33 -154 10 8 -149 27 8 -155 43 11 -151 20 9 48 0 0 11 46 57 19 193 -34 -149 47 40 -152 49 3 -148 1 9 -154 23 15 -149 52 32 47 0 0 11 46 43 19 195 -34 -148 18 0 -151 23 8 -146 28 43 -152 58 52 -148 19 2 46 0 0 11 46 27 20 196 -35 -146 41 50 -149 51 51 -144 48 54 -151 29 36 -146 38 49 45 0 0 11 46 11 21 198 -35 -144 58 8 -148 14 31 -143 0 25 -149 54 52 -144 50 47 44 0 0 11 45 53 21 200 -35 -143 5 32 -146 30 12 -141 1 28 -148 13 55 -142 53 25 43 0 0 11 45 33 22 202 -35 -141 2 6 -144 37 42 -138 49 20 -146 25 45 -140 44 31 42 0 0 11 45 12 22 204 -35 -138 44 51 -142 35 18 -136 19 40 -144 29 3 Latitude Latitude Latitude Latitude -140 0 0 41 40 40 11 45 5 22 204 -34 42 32 0 40 51 24 43 31 15 39 59 21 -139 0 0 41 15 41 11 44 55 22 205 -34 42 6 17 40 27 5 43 4 36 39 35 39 -138 0 0 40 51 56 11 44 45 22 206 -34 41 41 52 40 3 56 42 39 19 39 13 6 -137 0 0 40 29 24 11 44 35 22 207 -34 41 18 42 39 41 58 42 15 22 38 51 40 -136 0 0 40 8 4 11 44 25 22 208 -33 40 56 47 39 21 8 41 52 43 38 31 21 -135 0 0 39 47 54 11 44 16 22 209 -33 40 36 5 39 1 27 41 31 22 38 12 8 -134 0 0 39 28 54 11 44 6 22 210 -33 40 16 36 38 42 53 41 11 15 37 54 0 -133 0 0 39 11 2 11 43 57 22 211 -32 39 58 17 38 25 25 40 52 24 37 36 56 -132 0 0 38 54 18 11 43 47 22 212 -32 39 41 9 38 9 4 40 34 45 37 20 56 -131 0 0 38 38 42 11 43 38 22 213 -31 39 25 10 37 53 48 40 18 18 37 6 1 -130 0 0 38 24 13 11 43 29 22 214 -31 39 10 21 37 39 37 40 3 3 36 52 8 -129 0 0 38 10 50 11 43 20 21 215 -30 38 56 39 37 26 30 39 48 59 36 39 18 -128 0 0 37 58 33 11 43 11 21 215 -30 38 44 5 37 14 28 39 36 5 36 27 31 -127 0 0 37 47 21 11 43 2 21 216 -29 38 32 39 37 3 30 39 24 20 36 16 46 -126 0 0 37 37 14 11 42 54 20 217 -29 38 22 19 36 53 35 39 13 44 36 7 3 -125 0 0 37 28 12 11 42 45 20 218 -28 38 13 6 36 44 43 39 4 17 35 58 22 -124 0 0 37 20 15 11 42 37 20 219 -28 38 4 59 36 36 55 38 55 58 35 50 42 -123 0 0 37 13 22 11 42 29 19 220 -27 37 57 58 36 30 10 38 48 47 35 44 4 -122 0 0 37 7 34 11 42 21 19 221 -26 37 52 3 36 24 27 38 42 44 35 38 28 -121 0 0 37 2 50 11 42 13 18 221 -26 37 47 14 36 19 48 38 37 48 35 33 53 -120 0 0 36 59 10 11 42 6 18 222 -25 37 43 30 36 16 11 38 34 0 35 30 20 -119 0 0 36 56 34 11 41 58 17 223 -24 37 40 52 36 13 37 38 31 20 35 27 48 -118 0 0 36 55 3 11 41 51 17 224 -24 37 39 20 36 12 7 38 29 47 35 26 17 -117 0 0 36 54 36 11 41 44 16 224 -23 37 38 54 36 11 39 38 29 22 35 25 49 -116 0 0 36 55 14 11 41 37 16 225 -22 37 39 34 36 12 14 38 30 5 35 26 22 -115 0 0 36 56 56 11 41 31 15 226 -22 37 41 21 36 13 53 38 31 56 35 27 57 -114 0 0 36 59 44 11 41 24 15 227 -21 37 44 14 36 16 36 38 34 56 35 30 35 -113 0 0 37 3 37 11 41 18 14 227 -20 37 48 13 36 20 22 38 39 4 35 34 15 -112 0 0 37 8 35 11 41 12 13 228 -19 37 53 21 36 25 13 38 44 22 35 38 58 -111 0 0 37 14 40 11 41 7 13 229 -19 37 59 35 36 31 9 38 50 49 35 44 44 -110 0 0 37 21 51 11 41 2 12 229 -18 38 6 59 36 38 9 38 58 27 35 51 34 -109 0 0 37 30 10 11 40 57 11 230 -17 38 15 30 36 46 15 39 7 15 35 59 28 -108 0 0 37 39 36 11 40 52 11 231 -16 38 25 12 36 55 27 39 17 15 36 8 26 -107 0 0 37 50 10 11 40 47 10 231 -15 38 36 3 37 5 46 39 28 28 36 18 29 -106 0 0 38 1 53 11 40 43 9 232 -15 38 48 5 37 17 12 39 40 53 36 29 38 -105 0 0 38 14 46 11 40 39 9 233 -14 39 1 19 37 29 46 39 54 33 36 41 53 -104 0 0 38 28 49 11 40 36 8 233 -13 39 15 46 37 43 28 40 9 29 36 55 14 -103 0 0 38 44 4 11 40 32 7 234 -12 39 31 26 37 58 20 40 25 40 37 9 44 -102 0 0 39 0 32 11 40 29 6 235 -11 39 48 22 38 14 23 40 43 10 37 25 21 -101 0 0 39 18 12 11 40 27 5 235 -11 40 6 33 38 31 36 41 1 59 37 42 8 -100 0 0 39 37 8 11 40 25 5 236 -10 40 26 1 38 50 2 41 22 9 38 0 4 - 99 0 0 39 57 19 11 40 23 4 237 -9 40 46 49 39 9 41 41 43 41 38 19 12 - 98 0 0 40 18 48 11 40 21 3 237 -8 41 8 56 39 30 35 42 6 38 .. .. .. - 97 0 0 40 41 35 11 40 20 2 238 -7 41 32 26 39 52 45 42 31 1 .. .. .. - 96 0 0 41 5 43 11 40 19 1 238 -6 41 57 20 40 16 12 42 56 53 .. .. .. - 95 0 0 41 31 14 11 40 19 0 239 -6 .. .. .. 40 40 58 .. .. .. .. .. .. Uncertainty in time = +/- 5 secs Prediction of 2009 Mar 19.0 Data for the target star ------------------------ * name: 2UCAC 22924840 * constellation : Virgo * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 13 19 12.7613 DE: -22 20 46.470 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .025, .025 ) * V mag [mag]: 12.4 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (792) Metcalfia approx. diameter [km]: 61 approx. diameter ["]: .056 distance from Earth [AU]: 1.49000 * orbital information: orbit source: Preston date of fit: 2009 Mar 18 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 907 number of rejected observations: 68 time covered by the observations: 1915 Feb 04 - 2009 Feb 06 1 sigma uncertainty ellipse (major, minor, PA): 0.039, 0.018, 107° remarks: * orbital elements for (792) Metcalfia : Mean anomaly = 53.46655824 deg Arg. of pericenter = 227.40297070 deg Long. of node = 265.30617677 deg Inclination = 8.60918769 deg Eccentricity = 0.13275562 Semimajor axis = 2.62132960 AU Perihelion dist = 2.27333335 AU Mag: H = 10.10, G = 0.15 Epoch of elements : MJD 54920.48900000 TDT (2009 Mar 30.489) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Mar 30 792 Metcalfia 11h 44.6m UT 12.4 13 19 12.761-22 20 46.472UCAC 22924840 0.0 13.7 61 6.5 1.490 -2.080 11.56 -164.3573 -22.348 4.95 3.93 11.7441 0.34336 0.85719 -4.88639 1.95619 -0.00103 0.00174 2000 53.3529972009 330.00000227.402971265.306177 8.6091880.13275562 2.6213296 2.273333410.3 5.00.15 RATE 2.3223170 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.046 0.030 102 1.55 0.031 0 54909.0020090330_924840 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2009 Mar 18, 17:26 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org