IOTA/IOTA-ES occultation update for (132) Aethra / TYC 6846-00415-1 event on 2008 May 15, 20:17 UT Visible from Antarctica, S Africa Summary ------- On 2008 May 15 UT, the 43 km diameter asteroid (132) Aethra will occult a 11.8 mag star in the constellation Sagittarius for observers along a path across Antarctica, S Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.5 mag to 13.0 mag (the magnitude of the asteroid) for at most 3.5 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: 67 * date and approx. time of event: 2008 May 15, 20:11 - 2008 May 15, 20:23 UT * magnitude of target star: 11.8 * magnitude drop [mag]: 1.5 * estimated maximum duration [s]: 3.5 * Moon: 84 % sunlit, 81° distance * Sun: 145° distance * rough path description: Antarctica, S Africa The occultation path -------------------- * approximate projected width [km]: 62 * 1 sigma uncertainty interval [path widths]: +/- 0.89 * 1 sigma uncertainty interval [seconds]: +/- 2.6 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .038 +/- .026) * 1 sigma uncertainty ellipse (major, minor, PA): ( .039", .024", 71° ) * approx speed of asteroid's shadow [km/s]: 12.1849 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6846-00415-1 by 132 Aethra on 2008 May 15 Centre Star Star Sun Path Limit1 Path Limit2 Error Limit1 Error Limit2 E. Longitude Latitude U.T. Alt Az Alt o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " o ' " o ' " o ' " o ' " Longitude Latitude Longitude Latitude Longitude Latitude Longitude Latitude -105 24 0 -74 30 5 20 11 39 10 197 -4 -104 6 11 -73 46 4 -106 44 59 -75 10 20 -101 54 4 -72 15 13 -109 18 2 -76 14 26 -106 31 16 -77 42 40 20 11 48 14 199 -7 -105 5 27 -77 9 32 -108 2 12 -78 13 46 -102 44 17 -76 4 47 -110 57 48 -79 4 34 -107 7 16 -80 19 59 20 11 57 16 199 -10 -105 27 15 -79 52 12 -108 54 50 -80 46 15 -102 46 13 -78 58 52 -112 26 42 -81 29 28 -107 9 50 -82 36 45 20 12 6 18 200 -12 -105 8 27 -82 12 9 -109 22 57 -83 0 3 -101 58 9 -81 25 12 -113 52 35 -83 38 14 -106 19 43 -84 39 32 20 12 15 20 199 -14 -103 45 43 -84 16 52 -109 14 15 -85 0 57 - 99 54 18 -83 33 38 -115 24 54 -85 35 35 -103 32 17 -86 31 40 20 12 24 22 196 -16 -100 6 45 -86 9 52 -107 41 40 -86 52 7 - 95 22 30 -85 28 18 -117 29 40 -87 24 18 - 93 43 26 -88 13 38 20 12 33 24 187 -17 - 89 23 33 -87 51 10 -100 14 55 -88 34 47 - 84 34 40 -87 9 3 -123 28 39 -89 5 59 - 25 16 17 -89 20 49 20 12 42 25 119 -19 - 41 18 21 -89 1 55 9 29 48 -89 32 22 - 53 7 0 -88 22 54 73 0 55 -89 16 25 40 31 30 -88 17 6 20 12 51 26 53 -21 28 6 8 -88 22 6 51 14 45 -88 8 1 4 46 33 -88 18 46 65 39 24 -87 44 55 50 8 55 -86 50 31 20 13 0 28 44 -22 44 5 8 -86 59 43 55 33 3 -86 39 37 31 45 42 -87 10 43 63 38 24 -86 16 58 53 5 34 -85 25 11 20 13 9 29 42 -24 49 10 25 -85 35 17 56 41 27 -85 14 5 41 23 0 -85 50 14 62 21 18 -84 52 18 54 14 1 -84 2 21 20 13 19 30 41 -25 51 20 21 -84 12 36 56 56 27 -83 51 25 45 42 19 -84 28 50 61 19 28 -83 30 31 54 38 51 -82 42 1 20 13 28 31 41 -26 52 20 47 -82 52 9 56 49 34 -82 31 21 47 56 6 -83 8 43 60 25 5 -82 11 17 54 42 6 -81 23 57 20 13 37 32 41 -28 52 47 8 -81 33 52 56 31 53 -81 13 37 49 9 13 -81 50 24 59 35 6 -80 54 19 54 33 16 -80 7 57 20 13 46 33 42 -29 52 54 30 -80 17 38 56 8 12 -79 57 56 49 48 49 -80 33 56 58 48 5 -79 39 22 54 17 7 -78 53 50 20 13 55 34 43 -30 52 50 18 -79 3 15 55 40 59 -78 44 8 50 8 7 -79 19 15 58 3 10 -78 26 13 53 56 16 -77 41 25 20 14 4 35 44 -31 52 38 36 -77 50 34 55 11 33 -77 32 0 50 14 20 -78 6 13 57 19 53 -77 14 42 53 32 14 -76 30 32 20 14 13 35 45 -33 52 21 51 -76 39 26 54 40 41 -76 21 24 50 11 36 -76 54 43 56 37 52 -76 4 40 53 6 0 -75 21 3 20 14 22 36 46 -34 52 1 30 -75 29 43 54 8 52 -75 12 12 50 2 35 -75 44 37 55 56 54 -74 55 59 52 38 11 -74 12 51 20 14 31 37 47 -35 51 38 34 -74 21 16 53 36 25 -74 4 15 49 48 57 -74 35 48 55 16 47 -73 48 31 52 9 12 -73 5 49 20 14 40 37 48 -36 51 13 41 -73 14 1 53 3 32 -72 57 27 49 31 52 -73 28 11 54 37 24 -72 42 12 51 39 21 -71 59 52 20 14 49 38 49 -37 50 47 20 -72 7 51 52 30 21 -71 51 43 49 12 7 -72 21 40 53 58 38 -71 36 54 51 8 51 -70 54 53 20 14 58 39 50 -38 50 19 50 -71 2 40 51 56 57 -70 46 58 48 50 18 -71 16 9 53 20 24 -70 32 33 50 37 49 -69 50 49 20 15 7 39 51 -39 49 51 26 -69 58 24 51 23 24 -69 43 6 48 26 49 -70 11 33 52 42 36 -69 29 5 50 6 22 -68 47 35 20 15 17 40 53 -40 49 22 17 -68 54 59 50 49 44 -68 40 4 48 1 59 -69 7 49 52 5 11 -68 26 24 49 34 34 -67 45 7 20 15 26 40 54 -41 48 52 31 -67 52 20 50 15 58 -67 37 48 47 36 2 -68 4 52 51 28 5 -67 24 29 49 2 29 -66 43 22 20 15 35 41 55 -42 48 22 15 -66 50 24 49 42 8 -66 36 13 47 9 8 -67 2 38 50 51 16 -66 23 14 48 30 9 -65 42 16 20 15 44 41 57 -43 47 51 32 -65 49 8 49 8 13 -65 35 18 46 41 27 -66 1 5 50 14 40 -65 22 38 47 57 35 -64 41 46 20 15 53 41 58 -44 47 20 26 -64 48 28 48 34 14 -64 34 57 46 13 4 -65 0 9 49 38 16 -64 22 36 47 24 48 -63 41 49 20 16 2 42 59 -45 46 48 59 -63 48 22 48 0 10 -63 35 10 45 44 3 -63 59 47 49 2 0 -63 23 6 46 51 49 -62 42 23 20 16 11 42 61 -46 46 17 12 -62 48 47 47 26 1 -62 35 54 45 14 30 -62 59 56 48 25 51 -62 24 6 46 18 39 -61 43 25 20 16 20 42 62 -47 45 45 7 -61 49 40 46 51 46 -61 37 4 44 44 27 -62 0 34 47 49 46 -61 25 34 45 45 16 -60 44 53 20 16 29 43 63 -48 45 12 45 -60 51 0 46 17 25 -60 38 41 44 13 55 -61 1 39 47 13 45 -60 27 26 45 11 41 -59 46 44 20 16 38 43 65 -49 44 40 5 -59 52 42 45 42 57 -59 40 40 43 42 57 -60 3 7 46 37 44 -59 29 41 44 37 54 -58 48 56 20 16 47 43 66 -50 44 7 8 -58 54 47 45 8 20 -58 43 1 43 11 33 -59 4 57 46 1 42 -58 32 16 44 3 54 -57 51 28 20 16 56 43 67 -50 43 33 55 -57 57 11 44 33 34 -57 45 41 42 39 45 -58 7 8 45 25 38 -57 35 11 43 29 40 -56 54 17 20 17 5 43 69 -51 43 0 24 -56 59 52 43 58 38 -56 48 38 42 7 33 -57 9 35 44 49 29 -56 38 22 42 55 11 -55 57 22 20 17 15 43 70 -52 42 26 35 -56 2 49 43 23 30 -55 51 50 41 34 57 -56 12 19 44 13 14 -55 41 48 42 20 27 -55 0 40 20 17 24 43 71 -53 41 52 27 -55 6 0 42 48 10 -54 55 16 41 1 57 -55 15 17 43 36 52 -54 45 27 41 45 26 -54 4 10 20 17 33 43 73 -54 41 18 0 -54 9 23 42 12 36 -53 58 53 40 28 33 -54 18 27 43 0 20 -53 49 18 41 10 8 -53 7 50 20 17 42 43 74 -54 40 43 14 -53 12 55 41 36 47 -53 2 41 39 54 44 -53 21 47 42 23 37 -52 53 19 40 34 30 -52 11 39 20 17 51 43 76 -55 40 8 6 -52 16 37 41 0 41 -52 6 36 39 20 29 -52 25 15 41 46 41 -51 57 27 39 58 33 -51 15 34 20 18 0 43 77 -56 39 32 35 -51 20 25 40 24 17 -51 10 39 38 45 48 -51 28 51 41 9 31 -51 1 43 39 22 14 -50 19 34 20 18 9 43 78 -57 38 56 41 -50 24 18 39 47 33 -50 14 46 38 10 40 -50 32 31 40 32 5 -50 6 3 38 45 32 -49 23 38 20 18 18 43 80 -57 38 20 22 -49 28 14 39 10 28 -49 18 57 37 35 3 -49 36 15 39 54 21 -49 10 26 38 8 25 -48 27 43 20 18 27 42 81 -58 37 43 37 -48 32 12 38 33 0 -48 23 9 36 58 57 -48 40 1 39 16 16 -48 14 51 37 30 51 -47 31 48 20 18 36 42 82 -58 37 6 23 -47 36 10 37 55 7 -47 27 21 36 22 19 -47 43 46 38 37 49 -47 19 15 36 52 49 -46 35 51 20 18 45 42 84 -59 36 28 39 -46 40 6 37 16 48 -46 31 31 35 45 8 -46 47 29 37 58 58 -46 23 38 36 14 17 -45 39 50 20 18 54 42 85 -59 35 50 23 -45 43 58 36 37 59 -45 35 38 35 7 22 -45 51 8 37 19 41 -45 27 58 35 35 12 -44 43 44 20 19 3 41 86 -60 35 11 33 -44 47 45 35 58 39 -44 39 39 34 28 59 -44 54 42 36 39 55 -44 32 12 34 55 31 -43 47 31 20 19 13 41 88 -60 34 32 6 -43 51 24 35 18 45 -43 43 33 33 49 57 -43 58 8 35 59 38 -43 36 18 34 15 13 -42 51 8 20 19 22 40 89 -61 33 52 0 -42 54 53 34 38 14 -42 47 17 33 10 13 -43 1 24 35 18 46 -42 40 16 33 34 14 -41 54 33 20 19 31 40 90 -61 33 11 12 -41 58 11 33 57 5 -41 50 51 32 29 44 -42 4 28 34 37 18 -41 44 3 32 52 31 -40 57 45 20 19 40 39 91 -62 32 29 38 -41 1 16 33 15 13 -40 54 10 31 48 27 -41 7 18 33 55 10 -40 47 37 32 10 1 -40 0 41 20 19 49 39 92 -62 31 47 16 -40 4 3 32 32 35 -39 57 14 31 6 19 -40 9 51 33 12 18 -39 50 55 31 26 40 -39 3 19 20 19 58 38 94 -62 31 4 2 -39 6 33 31 49 7 -39 0 0 30 23 16 -39 12 5 32 28 39 -38 53 55 30 42 24 -38 5 35 20 20 7 38 95 -62 30 19 50 -38 8 40 31 4 46 -38 2 25 29 39 13 -38 13 57 31 44 9 -37 56 35 29 57 7 -37 7 28 20 20 16 37 96 -62 29 34 37 -37 10 24 30 19 26 -37 4 27 28 54 6 -37 15 24 30 58 42 -36 58 52 29 10 46 -36 8 53 20 20 25 36 97 -62 28 48 18 -36 11 39 29 33 3 -36 6 1 28 7 49 -36 16 22 30 12 15 -36 0 43 28 23 13 -35 9 47 20 20 34 36 98 -62 28 0 45 -35 12 23 28 45 30 -35 7 5 27 20 16 -35 16 48 29 24 42 -35 2 5 27 34 23 -34 10 7 20 20 43 35 99 -62 27 11 52 -34 12 33 27 56 41 -34 7 35 26 31 19 -34 16 38 28 35 55 -34 2 53 26 44 6 -33 9 48 20 20 52 34 100 -62 26 21 32 -33 12 2 27 6 28 -33 7 27 25 40 52 -33 15 47 27 45 48 -33 3 4 25 52 16 -32 8 44 20 21 1 33 101 -62 25 29 36 -32 10 47 26 14 44 -32 6 36 24 48 43 -32 14 9 26 54 13 -32 2 34 24 58 41 -31 6 52 20 21 11 32 102 -61 24 35 52 -31 8 41 25 21 17 -31 4 56 23 54 42 -31 11 39 26 1 0 -31 1 16 24 3 9 -30 4 3 20 21 20 31 103 -61 23 40 9 -30 5 38 24 25 57 -30 2 22 22 58 37 -30 8 10 25 5 58 -29 59 6 23 5 27 -29 0 11 20 21 29 30 104 -60 22 42 11 -29 1 30 23 28 29 -28 58 45 22 0 10 -29 3 32 24 8 54 -28 55 55 22 5 17 -27 55 6 20 21 38 29 105 -60 21 41 42 -27 56 7 22 28 37 -27 53 57 20 59 4 -27 57 37 23 9 33 -27 51 37 21 2 18 -26 48 38 20 21 47 28 106 -59 20 38 19 -26 49 20 21 26 1 -26 47 48 19 54 55 -26 50 13 22 7 35 -26 46 1 19 56 5 -25 40 33 20 21 56 27 107 -58 19 31 36 -25 40 52 20 20 17 -25 40 5 18 47 15 -25 41 3 21 2 38 -25 38 54 18 46 5 -24 30 35 20 22 5 25 108 -57 18 20 58 -24 30 28 19 10 53 -24 30 32 17 35 24 -24 29 49 19 54 14 -24 30 4 17 31 36 -23 18 22 20 22 14 24 109 -56 17 5 41 -23 17 44 17 57 9 -23 18 49 16 18 35 -23 16 7 18 41 45 -23 19 10 16 11 41 -22 3 26 20 22 23 23 109 -55 15 44 45 -22 2 11 16 38 12 -22 4 28 14 55 39 -21 59 22 17 24 23 -22 5 49 14 45 3 -20 45 8 20 22 32 21 110 -54 14 16 45 -20 43 6 15 12 49 -20 46 55 13 25 1 -20 38 47 16 1 4 -20 49 29 13 9 46 -19 22 31 20 22 41 19 111 -52 12 39 37 -19 19 28 13 39 15 -19 25 15 11 44 13 -19 13 9 14 30 15 -19 29 22 11 22 50 -17 54 8 20 22 50 17 112 -50 10 50 3 -17 49 40 11 54 46 -17 58 9 9 49 16 -17 40 31 12 49 38 -18 4 21 9 19 6 -16 17 25 20 22 59 15 113 -48 8 42 7 -16 10 48 9 54 45 -16 23 22 7 32 30 -15 57 9 10 55 25 -16 32 36 6 47 50 -14 27 11 20 23 9 12 113 -45 6 3 3 -14 16 40 7 30 11 -14 36 30 4 35 29 -13 54 7 8 40 38 -14 50 41 3 17 50 -12 8 22 20 23 18 8 114 -41 2 10 9 -11 46 42 4 17 5 -12 25 58 - 0 35 43 -10 46 15 5 49 11 -12 50 49 Uncertainty in time = +/- 4 secs [Prediction of 2008 May 8.0] Data for the target star ------------------------ * name: TYC 6846-00415-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 18 00 34.9820 DE: -25 21 40.730 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .022, .022 ) * V mag [mag]: 11.8 * B mag [mag]: 12.2 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (132) Aethra approx. diameter [km]: 43 approx. diameter ["]: .039 distance from Earth [AU]: 1.52500 * orbital information: orbit source: Preston date of fit: 2008 May 07 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 869 number of rejected observations: 52 time covered by the observations: 1932 Jun 21 - 2008 Apr 18 1 sigma uncertainty ellipse (major, minor, PA): 0.033, 0.011, 62° remarks: * orbital elements for (132) Aethra : Mean anomaly = 57.58988670 deg Arg. of pericenter = 254.40767251 deg Long. of node = 258.91557135 deg Inclination = 25.05029290 deg Eccentricity = 0.38799926 Semimajor axis = 2.60976098 AU Perihelion dist = 1.59717564 AU Mag: H = 8.91, G = 0.15 Epoch of elements : MJD 54601.84500000 TDT (2008 May 15.845) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 15 132 Aethra 20h 17.4m UT 11.8 18 0 34.982-25 21 40.73TYC 6846-00415-1 12.2 13.0 43 3.5 1.525 -2.331 23.99 91.8693 -25.369 -125.25 19.10 20.2899 -0.43809 -0.57766 -5.47636 4.16045 -0.00310 0.00015 2000 57.1585672008 514.00000254.407673258.915571 25.0502930.38799926 2.6097610 1.5971757 9.4 5.00.15 RATE 2.3377770 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.039 0.024 71 1.89 0.035 0 54594.5020080515_0415-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 May 08, 03:22 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org