IOTA/IOTA-ES occultation update for (503) Evelyn / 2UCAC 22105911 event on 2008 Mar 27, 08:34 UT Visible from Brazil, Argentina, Chile Summary ------- On 2008 Mar 27 UT, the 82 km diameter asteroid (503) Evelyn will occult a 11.0 mag star in the constellation Sagittarius for observers along a path across Brazil, Argentina, Chile. In the case of an occultation, the combined light of the asteroid and the star will drop by 4.1 mag to 15.1 mag (the magnitude of the asteroid) for at most 4.1 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: 78 * date and approx. time of event: 2008 Mar 27, 08:29 - 2008 Mar 27, 08:33 UT * midpoint of event [JD]: 2454552.85725417 * magnitude of target star: 11.0 * magnitude drop [mag]: 4.1 * estimated maximum duration [s]: 4.1 * Moon: 74 % sunlit, 39° distance * Sun: 80° distance * rough path description: Brazil, Argentina, Chile The occultation path -------------------- * approximate projected width [km]: 82 * 1 sigma uncertainty interval [path widths]: +/- 0.70 * 1 sigma uncertainty interval [seconds]: +/- 2.5 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .024 +/- .024) * 1 sigma uncertainty ellipse (major, minor, PA): ( .024", .024", 359° ) * approx speed of asteroid's shadow [km/s]: 20.1612 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 22105911 by 503 Evelyn on 2008 Mar 27 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 -116 0 0 - 7 34 4 8 29 12 1 114 -79 - 7 58 38 - 7 9 31 - 8 33 4 - 6 35 11 -115 0 0 - 8 0 58 8 29 12 2 114 -78 - 8 25 32 - 7 36 25 - 8 59 58 - 7 2 5 -114 0 0 - 8 27 49 8 29 12 3 114 -77 - 8 52 23 - 8 3 16 - 9 26 49 - 7 28 57 -113 0 0 - 8 54 37 8 29 13 4 114 -76 - 9 19 11 - 8 30 5 - 9 53 36 - 7 55 46 -112 0 0 - 9 21 21 8 29 13 5 114 -75 - 9 45 55 - 8 56 49 -10 20 20 - 8 22 31 -111 0 0 - 9 48 1 8 29 14 6 113 -74 -10 12 34 - 9 23 30 -10 46 58 - 8 49 12 -110 0 0 -10 14 35 8 29 14 7 113 -72 -10 39 8 - 9 50 4 -11 13 31 - 9 15 47 -109 0 0 -10 41 4 8 29 15 8 113 -71 -11 5 35 -10 16 33 -11 39 58 - 9 42 17 -108 0 0 -11 7 25 8 29 16 9 113 -70 -11 31 56 -10 42 56 -12 6 18 -10 8 40 -107 0 0 -11 33 40 8 29 17 10 113 -69 -11 58 10 -11 9 11 -12 32 30 -10 34 57 -106 0 0 -11 59 46 8 29 18 11 112 -68 -12 24 15 -11 35 18 -12 58 34 -11 1 5 -105 0 0 -12 25 44 8 29 19 12 112 -67 -12 50 12 -12 1 17 -13 24 29 -11 27 6 -104 0 0 -12 51 32 8 29 21 14 112 -66 -13 15 59 -12 27 7 -13 50 15 -11 52 57 -103 0 0 -13 17 11 8 29 22 15 112 -65 -13 41 37 -12 52 46 -14 15 51 -12 18 38 -102 0 0 -13 42 39 8 29 24 16 112 -64 -14 7 4 -13 18 16 -14 41 16 -12 44 10 -101 0 0 -14 7 56 8 29 25 17 111 -63 -14 32 20 -13 43 35 -15 6 30 -13 9 30 -100 0 0 -14 33 2 8 29 27 18 111 -62 -14 57 24 -14 8 42 -15 31 32 -13 34 39 - 99 0 0 -14 57 55 8 29 29 19 111 -61 -15 22 16 -14 33 37 -15 56 22 -13 59 36 - 98 0 0 -15 22 36 8 29 31 20 110 -60 -15 46 55 -14 58 19 -16 20 59 -14 24 21 - 97 0 0 -15 47 4 8 29 33 21 110 -59 -16 11 21 -15 22 48 -16 45 22 -14 48 52 - 96 0 0 -16 11 17 8 29 35 22 110 -58 -16 35 32 -15 47 3 -17 9 32 -15 13 10 - 95 0 0 -16 35 17 8 29 37 23 110 -57 -16 59 30 -16 11 4 -17 33 27 -15 37 13 - 94 0 0 -16 59 1 8 29 40 24 109 -55 -17 23 13 -16 34 51 -17 57 7 -16 1 2 - 93 0 0 -17 22 30 8 29 42 25 109 -54 -17 46 40 -16 58 22 -18 20 32 -16 24 36 - 92 0 0 -17 45 44 8 29 45 26 109 -53 -18 9 51 -17 21 37 -18 43 40 -16 47 54 - 91 0 0 -18 8 41 8 29 47 27 108 -52 -18 32 47 -17 44 37 -19 6 33 -17 10 56 - 90 0 0 -18 31 22 8 29 50 28 108 -51 -18 55 25 -18 7 19 -19 29 9 -17 33 42 - 89 0 0 -18 53 45 8 29 53 29 108 -50 -19 17 47 -18 29 45 -19 51 27 -17 56 10 - 88 0 0 -19 15 51 8 29 55 30 107 -49 -19 39 51 -18 51 53 -20 13 28 -18 18 22 - 87 0 0 -19 37 40 8 29 58 31 107 -48 -20 1 37 -19 13 44 -20 35 11 -18 40 15 - 86 0 0 -19 59 10 8 30 1 32 106 -47 -20 23 5 -19 35 16 -20 56 36 -19 1 51 - 85 0 0 -20 20 22 8 30 4 33 106 -46 -20 44 14 -19 56 30 -21 17 42 -19 23 8 - 84 0 0 -20 41 14 8 30 8 34 106 -45 -21 5 5 -20 17 25 -21 38 29 -19 44 6 - 83 0 0 -21 1 48 8 30 11 35 105 -44 -21 25 36 -20 38 1 -21 58 57 -20 4 45 - 82 0 0 -21 22 2 8 30 14 36 105 -43 -21 45 48 -20 58 17 -22 19 6 -20 25 5 - 81 0 0 -21 41 56 8 30 17 37 104 -42 -22 5 40 -21 18 14 -22 38 54 -20 45 5 - 80 0 0 -22 1 30 8 30 21 38 104 -41 -22 25 11 -21 37 51 -22 58 23 -21 4 45 - 79 0 0 -22 20 44 8 30 24 39 103 -40 -22 44 23 -21 57 7 -23 17 31 -21 24 4 - 78 0 0 -22 39 37 8 30 28 40 103 -39 -23 3 14 -22 16 2 -23 36 18 -21 43 3 - 77 0 0 -22 58 10 8 30 31 41 103 -38 -23 21 44 -22 34 37 -23 54 45 -22 1 41 - 76 0 0 -23 16 21 8 30 35 42 102 -37 -23 39 53 -22 52 51 -24 12 50 -22 19 59 - 75 0 0 -23 34 12 8 30 39 43 102 -36 -23 57 40 -23 10 44 -24 30 35 -22 37 55 - 74 0 0 -23 51 40 8 30 42 44 101 -35 -24 15 7 -23 28 15 -24 47 58 -22 55 29 - 73 0 0 -24 8 48 8 30 46 45 101 -34 -24 32 12 -23 45 25 -25 4 59 -23 12 42 - 72 0 0 -24 25 33 8 30 50 46 100 -33 -24 48 55 -24 2 12 -25 21 39 -23 29 33 - 71 0 0 -24 41 57 8 30 54 47 100 -32 -25 5 16 -24 18 38 -25 37 57 -23 46 2 - 70 0 0 -24 57 58 8 30 58 48 99 -31 -25 21 15 -24 34 42 -25 53 52 -24 2 10 - 69 0 0 -25 13 37 8 31 2 49 98 -30 -25 36 52 -24 50 24 -26 9 26 -24 17 54 - 68 0 0 -25 28 54 8 31 6 50 98 -30 -25 52 6 -25 5 43 -26 24 37 -24 33 17 - 67 0 0 -25 43 49 8 31 10 51 97 -29 -26 6 59 -25 20 40 -26 39 26 -24 48 17 - 66 0 0 -25 58 21 8 31 14 52 97 -28 -26 21 28 -25 35 14 -26 53 53 -25 2 54 - 65 0 0 -26 12 30 8 31 18 53 96 -27 -26 35 35 -25 49 26 -27 7 57 -25 17 9 - 64 0 0 -26 26 17 8 31 22 54 95 -26 -26 49 20 -26 3 15 -27 21 38 -25 31 1 - 63 0 0 -26 39 40 8 31 27 55 95 -25 -27 2 41 -26 16 41 -27 34 57 -25 44 30 - 62 0 0 -26 52 41 8 31 31 56 94 -24 -27 15 40 -26 29 44 -27 47 52 -25 57 36 - 61 0 0 -27 5 19 8 31 35 56 93 -23 -27 28 16 -26 42 24 -28 0 25 -26 10 19 - 60 0 0 -27 17 35 8 31 39 57 93 -22 -27 40 29 -26 54 41 -28 12 35 -26 22 39 - 59 0 0 -27 29 27 8 31 44 58 92 -21 -27 52 19 -27 6 35 -28 24 23 -26 34 36 - 58 0 0 -27 40 55 8 31 48 59 91 -20 -28 3 46 -27 18 6 -28 35 47 -26 46 10 - 57 0 0 -27 52 1 8 31 53 60 90 -19 -28 14 50 -27 29 14 -28 46 48 -26 57 20 - 56 0 0 -28 2 44 8 31 57 61 90 -18 -28 25 31 -27 39 58 -28 57 26 -27 8 7 - 55 0 0 -28 13 3 8 32 2 62 89 -17 -28 35 48 -27 50 19 -29 7 41 -27 18 31 - 54 0 0 -28 23 0 8 32 6 63 88 -17 -28 45 43 -28 0 17 -29 17 33 -27 28 32 - 53 0 0 -28 32 33 8 32 11 64 87 -16 -28 55 14 -28 9 52 -29 27 2 -27 38 9 - 52 0 0 -28 41 42 8 32 15 65 86 -15 -29 4 22 -28 19 4 -29 36 8 -27 47 23 - 51 0 0 -28 50 29 8 32 20 65 85 -14 -29 13 7 -28 27 52 -29 44 50 -27 56 13 - 50 0 0 -28 58 52 8 32 24 66 84 -13 -29 21 29 -28 36 16 -29 53 10 -28 4 40 - 49 0 0 -29 6 52 8 32 29 67 83 -12 -29 29 27 -28 44 18 -30 1 6 -28 12 43 - 48 0 0 -29 14 29 8 32 33 68 82 -11 -29 37 3 -28 51 56 -30 8 40 -28 20 23 - 47 0 0 -29 21 42 8 32 38 69 81 -10 -29 44 15 -28 59 11 -30 15 50 -28 27 40 - 46 0 0 -29 28 32 8 32 43 70 80 -9 -29 51 3 -29 6 2 -30 22 37 -28 34 33 - 45 0 0 -29 34 59 8 32 47 71 79 -8 -29 57 29 -29 12 30 -30 29 1 -28 41 3 - 44 0 0 -29 41 3 8 32 52 71 77 -8 -30 3 31 -29 18 35 -30 35 1 -28 47 9 - 43 0 0 -29 46 43 8 32 57 72 76 -7 -30 9 11 -29 24 16 -30 40 39 -28 52 52 - 42 0 0 -29 52 0 8 33 2 73 74 -6 -30 14 27 -29 29 34 -30 45 53 -28 58 11 - 41 0 0 -29 56 54 8 33 6 74 73 -5 -30 19 19 -29 34 29 -30 50 45 -29 3 7 - 40 0 0 -30 1 24 8 33 11 75 71 -4 -30 23 49 -29 39 0 -30 55 13 -29 7 40 - 39 0 0 -30 5 31 8 33 16 75 69 -3 -30 27 55 -29 43 8 -30 59 18 -29 11 49 - 38 0 0 -30 9 15 8 33 21 76 67 -2 -30 31 38 -29 46 52 -31 3 0 -29 15 34 - 37 0 0 -30 12 35 8 33 25 77 65 -1 -30 34 58 -29 50 14 -31 6 19 -29 18 57 - 36 0 0 -30 15 33 8 33 30 78 62 -1 -30 37 55 -29 53 12 -31 9 15 -29 21 55 Uncertainty in time = +/- 3 secs [Prediction of 2008 Feb 14.0] Data for the target star ------------------------ * name: 2UCAC 22105911 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 16 05.5315 DE: -24 00 47.782 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .021, .022 ) * V mag [mag]: 11.0 * B mag [mag]: 0.0 * Apparent position with proper motion RA(deg): 289.1496962607 DE(deg): -24.0000431007 * Equation of equinoxes (radians) : 0.000040692100927 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (503) Evelyn approx. diameter [km]: 82 approx. diameter ["]: .035 distance from Earth [AU]: 3.18500 * orbital information: orbit source: Preston date of fit: 2008 Feb 13 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 948 number of rejected observations: 114 time covered by the observations: 1903 Jan 19 - 2007 Aug 14 1 sigma uncertainty ellipse (major, minor, PA): 0.012, 0.010, 87° remarks: * orbital elements for (503) Evelyn : Mean anomaly = 151.45939947 deg Arg. of pericenter = 40.67423263 deg Long. of node = 69.19646158 deg Inclination = 5.02172175 deg Eccentricity = 0.17410447 Semimajor axis = 2.72798852 AU Perihelion dist = 2.25303352 AU Mag: H = 9.15, G = 0.15 Epoch of elements : MJD 54552.35700000 TDT (2008 Mar 27.357) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Mar 27 503 Evelyn 8h 34.4m UT 11.0 19 16 5.531-24 0 47.782UCAC 22105911 0.0 15.1 82 4.1 3.185 2.292 0.97 -24.7375 -24.014 52.72 2.80 8.5741 0.00472 -0.10770 11.37409 0.35250 -0.00569 -0.00077 2000 150.9438152008 325.00000 40.674233 69.196462 5.0217220.17410447 2.7279885 2.2530335 9.1 5.00.15 RATE 2.1874600 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.024 0.024 359 1.70 0.024 0 54510.5020080327_105911 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Feb 14, 19:54 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org