IOTA/IOTA-ES occultation update for (7) Iris / TYC 6273-01319-1 event on 2009 Sep 05, 03:19 UT Visible from Summary ------- On 2009 Sep 05 UT, the 200 km diameter asteroid (7) Iris will occult a 11.3 mag star in the constellation Sagittarius for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 0.3 mag to 9.9 mag (the magnitude of the asteroid) for at most 43.2 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: 2009 Sep 05, 03:14 - 2009 Sep 05, 03:36 UT * magnitude of target star: 11.3 * magnitude drop [mag]: 0.3 * estimated maximum duration [s]: 43.2 * Moon: 100 % sunlit, 73° distance * Sun: 112° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 282 * 1 sigma uncertainty interval [path widths]: +/- 0.31 * 1 sigma uncertainty interval [seconds]: +/- 7.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .025 +/- .046) * 1 sigma uncertainty ellipse (major, minor, PA): ( .046", .025", 360° ) * approx speed of asteroid's shadow [km/s]: 4.6279 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6273-01319-1 by 7 Iris on 2009 Sep 5 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 -135 0 0 26 47 35 3 14 35 42 158 0 25 31 26 28 5 26 24 45 2 28 54 39 -134 0 0 26 40 47 3 14 57 42 160 -1 25 24 42 27 58 35 24 38 19 28 47 45 -133 0 0 26 34 29 3 15 20 42 161 -2 25 18 27 27 52 14 24 32 7 28 41 21 -132 0 0 26 28 41 3 15 43 43 162 -3 25 12 43 27 46 23 24 26 24 28 35 28 -131 0 0 26 23 24 3 16 5 43 164 -4 25 7 28 27 41 3 24 21 11 28 30 6 -130 0 0 26 18 38 3 16 28 43 165 -5 25 2 44 27 36 13 24 16 28 28 25 15 -129 0 0 26 14 22 3 16 51 44 166 -6 24 58 30 27 31 55 24 12 16 28 20 56 -128 0 0 26 10 37 3 17 15 44 168 -7 24 54 47 27 28 8 24 8 34 28 17 8 -127 0 0 26 7 23 3 17 38 44 169 -8 24 51 35 27 24 53 24 5 23 28 13 51 -126 0 0 26 4 41 3 18 1 45 171 -9 24 48 54 27 22 9 24 2 42 28 11 6 -125 0 0 26 2 29 3 18 25 45 172 -10 24 46 44 27 19 57 24 0 33 28 8 53 -124 0 0 26 0 50 3 18 49 45 174 -11 24 45 5 27 18 16 23 58 54 28 7 12 -123 0 0 25 59 41 3 19 12 45 175 -12 24 43 57 27 17 7 23 57 47 28 6 3 -122 0 0 25 59 5 3 19 36 45 177 -13 24 43 21 27 16 30 23 57 11 28 5 25 -121 0 0 25 58 59 3 20 0 45 178 -14 24 43 15 27 16 25 23 57 5 28 5 20 -120 0 0 25 59 26 3 20 24 45 179 -15 24 43 41 27 16 52 23 57 31 28 5 47 -119 0 0 26 0 24 3 20 47 45 181 -16 24 44 39 27 17 50 23 58 28 28 6 46 -118 0 0 26 1 53 3 21 11 45 182 -17 24 46 7 27 19 21 23 59 56 28 8 17 -117 0 0 26 3 54 3 21 35 45 184 -18 24 48 7 27 21 23 24 1 55 28 10 20 -116 0 0 26 6 26 3 21 59 45 185 -19 24 50 38 27 23 57 24 4 25 28 12 55 -115 0 0 26 9 30 3 22 22 45 187 -20 24 53 40 27 27 2 24 7 26 28 16 2 -114 0 0 26 13 5 3 22 46 45 188 -21 24 57 13 27 30 39 24 10 58 28 19 40 -113 0 0 26 17 11 3 23 9 44 190 -22 25 1 16 27 34 47 24 15 0 28 23 50 -112 0 0 26 21 48 3 23 33 44 191 -22 25 5 51 27 39 27 24 19 33 28 28 31 -111 0 0 26 26 56 3 23 56 44 192 -23 25 10 56 27 44 38 24 24 37 28 33 44 -110 0 0 26 32 34 3 24 19 43 194 -24 25 16 31 27 50 19 24 30 10 28 39 28 -109 0 0 26 38 43 3 24 42 43 195 -25 25 22 37 27 56 32 24 36 14 28 45 43 -108 0 0 26 45 22 3 25 5 43 197 -26 25 29 12 28 3 15 24 42 47 28 52 28 -107 0 0 26 52 31 3 25 27 42 198 -27 25 36 18 28 10 28 24 49 50 28 59 44 -106 0 0 27 0 10 3 25 50 42 199 -28 25 43 52 28 18 11 24 57 22 29 7 30 -105 0 0 27 8 18 3 26 12 41 200 -28 25 51 56 28 26 24 25 5 24 29 15 45 -104 0 0 27 16 56 3 26 34 41 202 -29 26 0 29 28 35 6 25 13 54 29 24 31 -103 0 0 27 26 2 3 26 55 40 203 -30 26 9 31 28 44 18 25 22 53 29 33 46 -102 0 0 27 35 37 3 27 17 40 204 -31 26 19 1 28 53 58 25 32 20 29 43 29 -101 0 0 27 45 40 3 27 38 39 205 -32 26 28 59 29 4 6 25 42 15 29 53 42 -100 0 0 27 56 11 3 27 59 39 206 -32 26 39 24 29 14 43 25 52 37 30 4 22 - 99 0 0 28 7 9 3 28 19 38 208 -33 26 50 17 29 25 47 26 3 27 30 15 30 - 98 0 0 28 18 35 3 28 40 38 209 -34 27 1 37 29 37 19 26 14 43 30 27 6 - 97 0 0 28 30 27 3 29 0 37 210 -35 27 13 23 29 49 18 26 26 26 30 39 9 - 96 0 0 28 42 46 3 29 19 36 211 -35 27 25 35 30 1 43 26 38 35 30 51 38 - 95 0 0 28 55 30 3 29 39 36 212 -36 27 38 13 30 14 34 26 51 9 31 4 34 - 94 0 0 29 8 40 3 29 58 35 213 -37 27 51 17 30 27 50 27 4 8 31 17 55 - 93 0 0 29 22 14 3 30 16 34 214 -37 28 4 45 30 41 32 27 17 32 31 31 41 - 92 0 0 29 36 13 3 30 35 33 215 -38 28 18 37 30 55 38 27 31 20 31 45 52 - 91 0 0 29 50 36 3 30 52 33 216 -38 28 32 53 31 10 8 27 45 32 32 0 27 - 90 0 0 30 5 22 3 31 10 32 217 -39 28 47 32 31 25 2 28 0 7 32 15 26 - 89 0 0 30 20 31 3 31 27 31 218 -39 29 2 34 31 40 19 28 15 5 32 30 48 - 88 0 0 30 36 3 3 31 44 30 218 -40 29 17 58 31 55 58 28 30 25 32 46 32 - 87 0 0 30 51 56 3 32 0 30 219 -41 29 33 44 32 11 59 28 46 7 33 2 38 - 86 0 0 31 8 10 3 32 16 29 220 -41 29 49 51 32 28 21 29 2 9 33 19 6 - 85 0 0 31 24 45 3 32 31 28 221 -41 30 6 18 32 45 4 29 18 32 33 35 54 - 84 0 0 31 41 40 3 32 46 27 222 -42 30 23 6 33 2 7 29 35 15 33 53 2 - 83 0 0 31 58 54 3 33 0 26 223 -42 30 40 12 33 19 30 29 52 18 34 10 30 - 82 0 0 32 16 27 3 33 14 26 223 -43 30 57 38 33 37 11 30 9 39 34 28 17 - 81 0 0 32 34 19 3 33 28 25 224 -43 31 15 22 33 55 11 30 27 18 34 46 22 - 80 0 0 32 52 28 3 33 41 24 225 -43 31 33 23 34 13 28 30 45 14 35 4 45 - 79 0 0 33 10 53 3 33 54 23 226 -43 31 51 41 34 32 2 31 3 28 35 23 24 - 78 0 0 33 29 35 3 34 6 22 226 -44 32 10 15 34 50 53 31 21 58 35 42 20 - 77 0 0 33 48 33 3 34 18 21 227 -44 32 29 5 35 9 59 31 40 43 36 1 32 - 76 0 0 34 7 46 3 34 29 21 228 -44 32 48 10 35 29 19 31 59 43 36 20 58 - 75 0 0 34 27 12 3 34 40 20 229 -44 33 7 29 35 48 55 32 18 58 36 40 39 - 74 0 0 34 46 53 3 34 50 19 229 -44 33 27 2 36 8 43 32 38 27 37 0 33 - 73 0 0 35 6 46 3 35 0 18 230 -45 33 46 48 36 28 45 32 58 8 37 20 41 - 72 0 0 35 26 52 3 35 9 17 231 -45 34 6 46 36 48 59 33 18 2 37 41 0 - 71 0 0 35 47 9 3 35 18 16 231 -45 34 26 56 37 9 24 33 38 7 38 1 31 - 70 0 0 36 7 38 3 35 26 15 232 -45 34 47 16 37 30 1 33 58 24 38 22 12 - 69 0 0 36 28 16 3 35 34 15 233 -45 35 7 48 37 50 47 34 18 50 38 43 4 - 68 0 0 36 49 4 3 35 42 14 233 -45 35 28 28 38 11 43 34 39 27 39 4 5 - 67 0 0 37 10 1 3 35 48 13 234 -45 35 49 18 38 32 47 35 0 13 39 25 15 - 66 0 0 37 31 6 3 35 55 12 235 -44 36 10 16 38 54 0 35 21 6 39 46 33 - 65 0 0 37 52 18 3 36 1 11 235 -44 36 31 21 39 15 20 35 42 8 40 7 58 - 64 0 0 38 13 37 3 36 6 10 236 -44 36 52 34 39 36 47 36 3 17 40 29 29 - 63 0 0 38 35 3 3 36 11 9 237 -44 37 13 53 39 58 19 36 24 32 40 51 7 - 62 0 0 38 56 34 3 36 16 8 237 -44 37 35 17 40 19 57 36 45 52 41 12 50 - 61 0 0 39 18 9 3 36 20 8 238 -44 37 56 47 40 41 40 37 7 18 41 34 37 - 60 0 0 39 39 49 3 36 24 7 239 -43 38 18 20 41 3 27 37 28 48 41 56 28 - 59 0 0 40 1 33 3 36 27 6 239 -43 38 39 58 41 25 17 37 50 22 42 18 23 - 58 0 0 40 23 19 3 36 29 5 240 -43 39 1 38 41 47 9 38 11 59 42 40 19 - 57 0 0 40 45 7 3 36 32 4 241 -43 39 23 21 42 9 4 38 33 39 43 2 18 - 56 0 0 41 6 57 3 36 34 3 241 -42 39 45 6 42 31 0 38 55 21 43 24 18 - 55 0 0 41 28 48 3 36 35 3 242 -42 40 6 52 42 52 57 39 17 3 43 46 19 - 54 0 0 41 50 40 3 36 36 2 243 -41 40 28 38 43 14 53 39 38 47 44 8 19 - 53 0 0 42 12 31 3 36 37 1 243 -41 40 50 24 43 36 50 40 0 30 .. .. .. - 52 0 0 42 34 21 3 36 37 0 244 -41 41 12 10 .. .. .. 40 22 13 .. .. .. Uncertainty in time = +/- 13 secs [Prediction of 2008 Mar 20.0] Data for the target star ------------------------ * name: TYC 6273-01319-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 18 18 52.8203 DE: -18 58 58.924 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .024, .045 ) * V mag [mag]: 11.3 * B mag [mag]: 11.8 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (7) Iris approx. diameter [km]: 200 approx. diameter ["]: .148 distance from Earth [AU]: 1.86500 * orbital information: orbit source: Preston date of fit: 2008 Mar 20 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 4112 number of rejected observations: 310 time covered by the observations: 1901 Mar 27 - 2008 Mar 12 1 sigma uncertainty ellipse (major, minor, PA): 0.009, 0.008, 78° remarks: * orbital elements for (7) Iris : Mean anomaly = 278.82451820 deg Arg. of pericenter = 145.17737187 deg Long. of node = 259.71157755 deg Inclination = 5.52475520 deg Eccentricity = 0.23108312 Semimajor axis = 2.38621036 AU Perihelion dist = 1.83479743 AU Mag: H = 5.46, G = 0.15 Epoch of elements : MJD 55079.13900000 TDT (2009 Sep 05.139) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Sep 5 7 Iris 3h 20.3m UT 11.3 18 18 52.820-18 58 58.92TYC 6273-01319-1 11.8 9.9 200 43.2 1.865 0.869 0.13 -119.7366 -18.982 129.61 6.79 3.3390 -0.00863 0.70438 2.61199 0.02768 0.00508 0.00001 2000 276.3808642009 827.00000145.177372259.711578 5.5247550.23108312 2.3862104 1.8347974 5.5 5.00.15 RATE 2.6738750 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.046 0.025 360 1.31 0.046 0 54545.5020090905_1319-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 20, 12:56 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org