IOTA/IOTA-ES occultation update for (94) Aurora / 2UCAC 19531443 event on 2012 Oct 06, 03:27 UT Visible from S USA, Mexico Summary ------- On 2012 Oct 06 UT, the 218 km diameter asteroid (94) Aurora will occult a 12.4 mag star in the constellation Sagittarius for observers along a path across S USA, Mexico. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.4 mag to 13.5 mag (the magnitude of the asteroid) for at most 14.5 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: 98 * date and approx. time of event: 2012 Oct 06, 03:28 - 2012 Oct 06, 03:33 UT * geocentric midpoint of event [JD]: 2456206.6441625 * magnitude of target star: 12.4 * magnitude drop [mag]: 1.4 * estimated maximum duration [s]: 14.5 * Moon: 70 % sunlit, 153° distance * Sun: 92° distance * rough path description: S USA, Mexico The occultation path -------------------- * approximate projected width [km]: 248 * 1 sigma uncertainty interval [path widths]: +/- 0.34 * 1 sigma uncertainty interval [seconds]: +/- 4.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .033 +/- .033) * 1 sigma uncertainty ellipse (major, minor, PA): ( .033", .033", 89° ) * approx speed of asteroid's shadow [km/s]: 15.0518 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 19531443 by 94 Aurora on 2012 Oct 6 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 -144 0 0 - 0 29 48 3 28 30 60 173 -1 - 1 43 35 0 44 56 - 2 33 15 1 36 21 -143 0 0 - 0 1 4 3 28 38 60 175 -2 - 1 15 14 1 14 4 - 2 5 8 2 5 46 -142 0 0 0 28 30 3 28 46 60 177 -3 - 0 46 3 1 44 2 - 1 36 13 2 36 1 -141 0 0 0 58 53 3 28 55 59 178 -4 - 0 16 3 2 14 50 - 1 6 29 3 7 6 -140 0 0 1 30 6 3 29 3 59 180 -5 0 14 45 2 46 28 - 0 35 56 3 39 1 -139 0 0 2 2 8 3 29 11 58 182 -6 0 46 22 3 18 55 - 0 4 35 4 11 46 -138 0 0 2 34 58 3 29 20 58 183 -8 1 18 48 3 52 12 0 27 33 4 45 21 -137 0 0 3 8 37 3 29 28 57 185 -9 1 52 1 4 26 17 1 0 30 5 19 45 -136 0 0 3 43 5 3 29 36 56 187 -10 2 26 3 5 1 11 1 34 15 5 54 58 -135 0 0 4 18 20 3 29 45 56 188 -11 3 0 51 5 36 54 2 8 46 6 31 0 -134 0 0 4 54 22 3 29 53 55 189 -12 3 36 27 6 13 24 2 44 4 7 7 49 -133 0 0 5 31 11 3 30 1 54 191 -13 4 12 49 6 50 41 3 20 9 7 45 26 -132 0 0 6 8 46 3 30 9 53 192 -14 4 49 57 7 28 44 3 56 59 8 23 49 -131 0 0 6 47 7 3 30 17 52 193 -15 5 27 51 8 7 33 4 34 34 9 2 59 -130 0 0 7 26 12 3 30 25 51 195 -16 6 6 28 8 47 7 5 12 54 9 42 53 -129 0 0 8 6 1 3 30 33 51 196 -17 6 45 50 9 27 26 5 51 57 10 23 32 -128 0 0 8 46 34 3 30 41 50 197 -18 7 25 54 10 8 27 6 31 43 11 4 54 -127 0 0 9 27 48 3 30 49 49 198 -19 8 6 41 10 50 11 7 12 11 11 46 58 -126 0 0 10 9 43 3 30 57 48 199 -20 8 48 8 11 32 35 7 53 20 12 29 43 -125 0 0 10 52 18 3 31 4 47 200 -21 9 30 15 12 15 39 8 35 9 13 13 8 -124 0 0 11 35 32 3 31 12 46 201 -22 10 13 1 12 59 22 9 17 36 13 57 11 -123 0 0 12 19 23 3 31 19 45 202 -23 10 56 24 13 43 42 10 0 41 14 41 52 -122 0 0 13 3 49 3 31 26 44 203 -24 11 40 23 14 28 37 10 44 22 15 27 8 -121 0 0 13 48 50 3 31 34 42 203 -25 12 24 56 15 14 7 11 28 37 16 12 58 -120 0 0 14 34 24 3 31 41 41 204 -26 13 10 3 16 0 9 12 13 26 16 59 20 -119 0 0 15 20 29 3 31 47 40 205 -27 13 55 41 16 46 42 12 58 46 17 46 13 -118 0 0 16 7 2 3 31 54 39 206 -28 14 41 48 17 33 43 13 44 36 18 33 34 -117 0 0 16 54 4 3 32 1 38 206 -29 15 28 23 18 21 12 14 30 55 19 21 22 -116 0 0 17 41 30 3 32 7 37 207 -30 16 15 25 19 9 5 15 17 39 20 9 34 -115 0 0 18 29 21 3 32 13 36 208 -31 17 2 50 19 57 22 16 4 48 20 58 9 -114 0 0 19 17 32 3 32 20 35 208 -32 17 50 38 20 45 59 16 52 20 21 47 4 -113 0 0 20 6 3 3 32 25 33 209 -33 18 38 45 21 34 54 17 40 12 22 36 17 -112 0 0 20 54 51 3 32 31 32 210 -34 19 27 10 22 24 6 18 28 22 23 25 46 -111 0 0 21 43 53 3 32 37 31 210 -34 20 15 50 23 13 32 19 16 48 24 15 29 -110 0 0 22 33 8 3 32 42 30 211 -35 21 4 44 24 3 9 20 5 29 25 5 22 -109 0 0 23 22 33 3 32 47 29 212 -36 21 53 49 24 52 55 20 54 20 25 55 23 -108 0 0 24 12 6 3 32 52 27 212 -37 22 43 3 25 42 48 21 43 21 26 45 30 -107 0 0 25 1 44 3 32 57 26 213 -38 23 32 23 26 32 45 22 32 29 27 35 41 -106 0 0 25 51 25 3 33 1 25 213 -38 24 21 46 27 22 44 23 21 42 28 25 53 -105 0 0 26 41 6 3 33 5 24 214 -39 25 11 12 28 12 42 24 10 57 29 16 3 -104 0 0 27 30 45 3 33 9 23 215 -40 26 0 36 29 2 36 25 0 12 30 6 8 -103 0 0 28 20 19 3 33 13 21 215 -40 26 49 57 29 52 25 25 49 24 30 56 7 -102 0 0 29 9 46 3 33 17 20 216 -41 27 39 12 30 42 5 26 38 31 31 45 56 -101 0 0 29 59 4 3 33 20 19 216 -41 28 28 19 31 31 34 27 27 31 32 35 34 -100 0 0 30 48 10 3 33 24 18 217 -42 29 17 15 32 20 50 28 16 21 33 24 57 - 99 0 0 31 37 2 3 33 26 17 217 -42 30 5 59 33 9 51 29 4 59 34 14 4 - 98 0 0 32 25 37 3 33 29 16 218 -43 30 54 27 33 58 33 29 53 24 35 2 52 - 97 0 0 33 13 53 3 33 32 14 219 -43 31 42 38 34 46 56 30 41 31 35 51 18 - 96 0 0 34 1 49 3 33 34 13 219 -43 32 30 30 35 34 55 31 29 21 36 39 21 - 95 0 0 34 49 22 3 33 36 12 220 -44 33 18 0 36 22 31 32 16 49 37 26 59 - 94 0 0 35 36 29 3 33 38 11 220 -44 34 5 7 37 9 40 33 3 55 38 14 9 - 93 0 0 36 23 10 3 33 40 10 221 -44 34 51 48 37 56 20 33 50 37 39 0 49 - 92 0 0 37 9 22 3 33 41 9 222 -45 35 38 2 38 42 30 34 36 52 39 46 58 - 91 0 0 37 55 3 3 33 43 8 222 -45 36 23 46 39 28 8 35 22 39 40 32 34 - 90 0 0 38 40 13 3 33 44 7 223 -45 37 9 0 40 13 13 36 7 56 41 17 35 - 89 0 0 39 24 48 3 33 45 6 224 -45 37 53 42 40 57 42 36 52 41 42 2 0 - 88 0 0 40 8 49 3 33 45 4 224 -45 38 37 50 41 41 35 37 36 54 42 45 47 - 87 0 0 40 52 12 3 33 46 3 225 -45 39 21 22 42 24 50 38 20 33 43 28 55 - 86 0 0 41 34 59 3 33 46 2 226 -45 40 4 19 43 7 25 39 3 36 44 11 23 - 85 0 0 42 17 6 3 33 47 1 226 -45 40 46 38 43 49 21 39 46 2 .. .. .. - 84 0 0 42 58 34 3 33 47 0 227 -45 41 28 18 .. .. .. 40 27 50 .. .. .. Uncertainty in time = +/- 5 secs Prediction of 2012 Sep 27.0 Data for the target star ------------------------ * name: 2UCAC 19531443 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 08 40.1951 DE: -29 52 19.228 * position source: mpos:UCAC4 pm:UCAC4 * standard error: RA,DE ["]: ( .032, .032 ) * V mag [mag]: 12.4 * B mag [mag]: 0.0 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (94) Aurora approx. diameter [km]: 218 approx. diameter ["]: .097 distance from Earth [AU]: 3.09300 * orbital information: orbit source: Preston date of fit: 2012 Sep 26 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1122 number of rejected observations: 97 time covered by the observations: 1901 Oct 14 - 2012 Sep 20 1 sigma uncertainty ellipse (major, minor, PA): 0.009, 0.007, 81° remarks: * orbital elements for (94) Aurora : Mean anomaly = 248.78440827 deg Arg. of pericenter = 60.24621659 deg Long. of node = 2.66699636 deg Inclination = 7.96464137 deg Eccentricity = 0.08921773 Semimajor axis = 3.15896799 AU Perihelion dist = 2.87713203 AU Mag: H = 7.53, G = 0.15 Epoch of elements : MJD 56206.14400000 TDT (2012 Oct 06.144) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Oct 6 94 Aurora 3h 27.6m UT 12.4 19 8 40.195-29 52 19.232UCAC 19531443 0.0 13.5 218 14.5 3.093 1.706 9.57 -139.9323 -29.874 125.13 -5.25 3.4599 -0.18783 0.43843 7.80079 3.36516 0.00580 0.00072 2000 247.7058652012 930.00000 60.246217 2.666996 7.9646410.08921773 3.1589680 2.8771320 7.6 5.00.15 RATE 1.7554410 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.033 0.033 89 1.34 0.033 0 0 1 2 056197.0020121006_531443 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Sep 26, 22:00 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org