IOTA/IOTA-ES occultation update for (1488) Aura / TYC 1406-01149-1 event on 2008 May 18, 15:13 UT Visible from India, SE Asia Summary ------- On 2008 May 18 UT, the 23 km diameter asteroid (1488) Aura will occult a 9.4 mag star in the constellation Leo for observers along a path across India, SE Asia. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.8 mag to 16.2 mag (the magnitude of the asteroid) for at most 1.0 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: 24 * date and approx. time of event: 2008 May 18, 15:13 - 2008 May 18, 15:17 UT * midpoint of event [JD]: 2454605.134125 * magnitude of target star: 9.4 * magnitude drop [mag]: 6.8 * estimated maximum duration [s]: 1.0 * Moon: 98 % sunlit, 84° distance * Sun: 81° distance * rough path description: India, SE Asia The occultation path -------------------- * approximate projected width [km]: 25 * 1 sigma uncertainty interval [path widths]: +/- 2.82 * 1 sigma uncertainty interval [seconds]: +/- 3.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .035 +/- .034) * 1 sigma uncertainty ellipse (major, minor, PA): ( .035", .034", 100° ) * approx speed of asteroid's shadow [km/s]: 22.4496 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1406-01149-1 by 1488 Aura on 2008 May 18 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 57 0 0 36 29 25 15 13 30 64 229 -1 36 20 40 36 38 11 35 31 30 37 27 54 58 0 0 35 50 53 15 13 35 64 231 -2 35 42 7 35 59 41 34 52 52 36 49 29 59 0 0 35 11 53 15 13 40 64 234 -3 35 3 6 35 20 41 34 13 47 36 10 35 60 0 0 34 32 26 15 13 45 64 237 -4 34 23 38 34 41 15 33 34 15 35 31 13 61 0 0 33 52 34 15 13 51 63 239 -5 33 43 45 34 1 23 32 54 18 34 51 24 62 0 0 33 12 16 15 13 56 63 242 -6 33 3 27 33 21 6 32 13 57 34 11 10 63 0 0 32 31 36 15 14 1 62 244 -7 32 22 46 32 40 26 31 33 14 33 30 33 64 0 0 31 50 34 15 14 7 62 247 -8 31 41 44 31 59 24 30 52 10 32 49 33 65 0 0 31 9 11 15 14 12 61 249 -9 31 0 21 31 18 2 30 10 46 32 8 11 66 0 0 30 27 30 15 14 17 61 251 -10 30 18 40 30 36 21 29 29 4 31 26 30 67 0 0 29 45 31 15 14 23 60 253 -11 29 36 41 29 54 22 28 47 6 30 44 32 68 0 0 29 3 17 15 14 28 59 256 -13 28 54 27 29 12 8 28 4 53 30 2 16 69 0 0 28 20 49 15 14 33 59 258 -14 28 11 59 28 29 39 27 22 26 29 19 47 70 0 0 27 38 8 15 14 39 58 259 -15 27 29 19 27 46 58 26 39 48 28 37 4 71 0 0 26 55 18 15 14 44 57 261 -16 26 46 29 27 4 7 25 57 0 27 54 10 72 0 0 26 12 18 15 14 49 56 263 -17 26 3 30 26 21 7 25 14 5 27 11 7 73 0 0 25 29 12 15 14 55 56 265 -18 25 20 24 25 38 0 24 31 3 26 27 56 74 0 0 24 46 1 15 15 0 55 266 -19 24 37 14 24 54 48 23 47 57 25 44 39 75 0 0 24 2 46 15 15 5 54 268 -21 23 54 0 24 11 33 23 4 48 25 1 19 76 0 0 23 19 30 15 15 10 53 269 -22 23 10 45 23 28 16 22 21 39 24 17 56 77 0 0 22 36 15 15 15 15 52 270 -23 22 27 31 22 45 0 21 38 31 23 34 33 78 0 0 21 53 2 15 15 21 51 272 -24 21 44 19 22 1 45 20 55 26 22 51 13 79 0 0 21 9 53 15 15 26 50 273 -25 21 1 12 21 18 35 20 12 25 22 7 55 80 0 0 20 26 50 15 15 31 49 274 -27 20 18 10 20 35 31 19 29 31 21 24 43 81 0 0 19 43 55 15 15 35 48 275 -28 19 35 17 19 52 35 18 46 46 20 41 39 82 0 0 19 1 10 15 15 40 47 276 -29 18 52 33 19 9 48 18 4 10 19 58 43 83 0 0 18 18 36 15 15 45 46 277 -30 18 10 0 18 27 12 17 21 47 19 15 58 84 0 0 17 36 15 15 15 50 45 278 -31 17 27 41 17 44 49 16 39 36 18 33 26 85 0 0 16 54 8 15 15 54 44 279 -33 16 45 36 17 2 41 15 57 41 17 51 8 86 0 0 16 12 18 15 15 59 43 280 -34 16 3 48 16 20 49 15 16 3 17 9 6 87 0 0 15 30 46 15 16 3 42 280 -35 15 22 17 15 39 15 14 34 42 16 27 21 88 0 0 14 49 33 15 16 8 41 281 -36 14 41 6 14 58 0 13 53 42 15 45 56 89 0 0 14 8 41 15 16 12 40 282 -37 14 0 16 14 17 6 13 13 2 15 4 51 90 0 0 13 28 11 15 16 16 38 282 -39 13 19 48 13 36 35 12 32 46 14 24 8 91 0 0 12 48 5 15 16 20 37 283 -40 12 39 44 12 56 27 11 52 53 13 43 48 92 0 0 12 8 24 15 16 24 36 283 -41 12 0 5 12 16 43 11 13 25 13 3 53 93 0 0 11 29 9 15 16 28 35 284 -42 11 20 52 11 37 26 10 34 24 12 24 24 94 0 0 10 50 22 15 16 31 34 284 -43 10 42 7 10 58 37 9 55 50 11 45 23 95 0 0 10 12 3 15 16 35 33 285 -44 10 3 50 10 20 16 9 17 45 11 6 49 96 0 0 9 34 13 15 16 38 32 285 -46 9 26 3 9 42 24 8 40 9 10 28 46 97 0 0 8 56 54 15 16 42 31 285 -47 8 48 46 9 5 3 8 3 5 9 51 12 98 0 0 8 20 7 15 16 45 29 286 -48 8 12 1 8 28 14 7 26 32 9 14 11 99 0 0 7 43 52 15 16 48 28 286 -49 7 35 48 7 51 57 6 50 31 8 37 41 100 0 0 7 8 11 15 16 51 27 286 -50 7 0 9 7 16 13 6 15 4 8 1 45 101 0 0 6 33 3 15 16 54 26 287 -51 6 25 4 6 41 4 5 40 10 7 26 23 102 0 0 5 58 31 15 16 56 25 287 -52 5 50 33 6 6 29 5 5 52 6 51 36 103 0 0 5 24 33 15 16 59 24 287 -54 5 16 38 5 32 29 4 32 9 6 17 25 104 0 0 4 51 12 15 17 2 23 287 -55 4 43 19 4 59 6 3 59 1 5 43 49 105 0 0 4 18 28 15 17 4 22 287 -56 4 10 37 4 26 19 3 26 31 5 10 50 106 0 0 3 46 20 15 17 6 20 288 -57 3 38 31 3 54 10 2 54 37 4 38 29 107 0 0 3 14 50 15 17 8 19 288 -58 3 7 4 3 22 38 2 23 21 4 6 45 108 0 0 2 43 59 15 17 10 18 288 -59 2 36 14 2 51 44 1 52 43 3 35 39 109 0 0 2 13 45 15 17 12 17 288 -60 2 6 2 2 21 28 1 22 43 3 5 12 110 0 0 1 44 10 15 17 14 16 288 -61 1 36 30 1 51 52 0 53 21 2 35 24 111 0 0 1 15 15 15 17 15 15 288 -62 1 7 36 1 22 54 0 24 39 2 6 15 112 0 0 0 46 58 15 17 17 14 288 -63 0 39 22 0 54 36 - 0 3 25 1 37 45 113 0 0 0 19 22 15 17 18 13 288 -64 0 11 47 0 26 57 - 0 30 49 1 9 56 114 0 0 - 0 7 35 15 17 20 12 288 -65 - 0 15 8 - 0 0 2 - 0 57 34 0 42 46 115 0 0 - 0 33 52 15 17 21 10 288 -66 - 0 41 24 - 0 26 21 - 1 23 38 0 16 16 116 0 0 - 0 59 30 15 17 22 9 288 -67 - 1 6 59 - 0 52 0 - 1 49 4 - 0 9 33 117 0 0 - 1 24 27 15 17 23 8 288 -68 - 1 31 54 - 1 16 58 - 2 13 49 - 0 34 42 118 0 0 - 1 48 43 15 17 24 7 288 -69 - 1 56 9 - 1 41 17 - 2 37 54 - 0 59 11 119 0 0 - 2 12 20 15 17 24 6 288 -70 - 2 19 44 - 2 4 55 - 3 1 19 - 1 22 58 120 0 0 - 2 35 16 15 17 25 5 288 -70 - 2 42 38 - 2 27 53 - 3 24 4 - 1 46 6 121 0 0 - 2 57 31 15 17 25 4 288 -71 - 3 4 52 - 2 50 10 .. .. .. - 2 8 32 122 0 0 - 3 19 7 15 17 26 3 288 -72 - 3 26 26 - 3 11 47 .. .. .. - 2 30 18 123 0 0 - 3 40 2 15 17 26 2 288 -73 - 3 47 19 - 3 32 44 .. .. .. - 2 51 24 124 0 0 - 4 0 16 15 17 26 1 288 -73 - 4 7 33 - 3 53 0 .. .. .. - 3 11 48 Uncertainty in time = +/- 3 secs [Prediction of 2008 Apr 13.0] Data for the target star ------------------------ * name: TYC 1406-01149-1 * constellation : Leo * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 09 28 23.9373 DE: +17 48 25.322 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .029, .030 ) * V mag [mag]: 9.4 * B mag [mag]: 9.9 * Apparent position with proper motion RA(deg): 142.2184836762 DE(deg): 17.7711420694 * Equation of equinoxes (radians) : 0.000039498900387 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1488) Aura approx. diameter [km]: 23 approx. diameter ["]: .012 distance from Earth [AU]: 2.75100 * orbital information: orbit source: Preston date of fit: 2008 Apr 08 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 691 number of rejected observations: 30 time covered by the observations: 1905 Sep 19 - 2008 Mar 30 1 sigma uncertainty ellipse (major, minor, PA): 0.021, 0.016, 119° remarks: * orbital elements for (1488) Aura : Mean anomaly = 41.16963027 deg Arg. of pericenter = 113.31773473 deg Long. of node = 354.67411381 deg Inclination = 10.55568788 deg Eccentricity = 0.12359873 Semimajor axis = 3.03576807 AU Perihelion dist = 2.66055099 AU Mag: H = 10.20, G = 0.15 Epoch of elements : MJD 54604.63400000 TDT (2008 May 18.634) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 18 1488 Aura 15h 13.1m UT 9.4 9 28 23.937 17 48 25.32TYC 1406-01149-1 9.9 16.2 23 1.0 2.751 2.468 -19.95 37.1383 17.813 -49.17 19.73 15.2190 0.20778 0.36905 11.02683 -6.24240 0.00524 -0.00169 2000 40.3061402008 514.00000113.317735354.674114 10.5556880.12359873 3.0357681 2.660551010.8 5.00.15 RATE 1.8633790 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.035 0.034 100 3.82 0.034 0 54569.5020080518_1149-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 13, 03:12 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org