IOTA/IOTA-ES occultation update for (19) Fortuna / 2UCAC 22754721 event on 2008 Mar 04, 09:04 UT Visible from Brazil, Ecuador Summary ------- On 2008 Mar 04 UT, the 221 km diameter asteroid (19) Fortuna will occult a 12.0 mag star in the constellation Sagittarius for observers along a path across Brazil, Ecuador. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.1 mag to 12.6 mag (the magnitude of the asteroid) for at most 9.1 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: 99 * date and approx. time of event: 2008 Mar 04, 08:59 - 2008 Mar 04, 09:02 UT * magnitude of target star: 12.0 * magnitude drop [mag]: 1.1 * estimated maximum duration [s]: 9.1 * Moon: 12 % sunlit, 35° distance * Sun: 76° distance * rough path description: Brazil, Ecuador The occultation path -------------------- * approximate projected width [km]: 227 * 1 sigma uncertainty interval [path widths]: +/- 0.22 * 1 sigma uncertainty interval [seconds]: +/- 1.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .024 +/- .024) * 1 sigma uncertainty ellipse (major, minor, PA): ( .024", .024", 90° ) * approx speed of asteroid's shadow [km/s]: 24.2731 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 22754721 by 19 Fortuna on 2008 Mar 4 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 -114 0 0 11 30 42 8 59 45 0 113 -71 10 23 59 .. .. .. 9 54 43 .. .. .. -113 0 0 11 5 36 8 59 45 1 113 -71 9 58 54 12 12 37 9 29 39 12 42 13 -112 0 0 10 40 31 8 59 45 2 113 -70 9 33 51 11 47 31 9 4 36 12 17 6 -111 0 0 10 15 29 8 59 46 3 114 -69 9 8 50 11 22 26 8 39 37 11 52 1 -110 0 0 9 50 30 8 59 46 4 114 -68 8 43 54 10 57 25 8 14 41 11 26 59 -109 0 0 9 25 35 8 59 47 5 114 -67 8 19 1 10 32 28 7 49 49 11 2 1 -108 0 0 9 0 44 8 59 47 7 114 -66 7 54 13 10 7 35 7 25 3 10 37 6 -107 0 0 8 35 59 8 59 48 8 114 -65 7 29 31 9 42 47 7 0 21 10 12 17 -106 0 0 8 11 20 8 59 48 9 114 -64 7 4 54 9 18 5 6 35 46 9 47 34 -105 0 0 7 46 47 8 59 49 10 115 -63 6 40 24 8 53 29 6 11 18 9 22 56 -104 0 0 7 22 21 8 59 50 11 115 -62 6 16 2 8 29 0 5 46 57 8 58 25 -103 0 0 6 58 3 8 59 51 12 115 -61 5 51 47 8 4 38 5 22 44 8 34 2 -102 0 0 6 33 53 8 59 52 13 115 -60 5 27 41 7 40 24 4 58 39 8 9 47 -101 0 0 6 9 52 8 59 53 14 115 -59 5 3 44 7 16 19 4 34 43 7 45 40 -100 0 0 5 46 0 8 59 55 15 115 -58 4 39 56 6 52 24 4 10 57 7 21 43 - 99 0 0 5 22 19 8 59 56 16 115 -57 4 16 19 6 28 38 3 47 22 6 57 55 - 98 0 0 4 58 48 8 59 57 17 115 -56 3 52 52 6 5 3 3 23 57 6 34 18 - 97 0 0 4 35 28 8 59 59 18 116 -55 3 29 37 5 41 38 3 0 44 6 10 52 - 96 0 0 4 12 20 9 0 1 19 116 -54 3 6 33 5 18 26 2 37 42 5 47 37 - 95 0 0 3 49 24 9 0 2 20 116 -53 2 43 42 4 55 25 2 14 53 5 24 35 - 94 0 0 3 26 41 9 0 4 22 116 -52 2 21 4 4 32 37 1 52 17 5 1 45 - 93 0 0 3 4 12 9 0 6 23 116 -51 1 58 39 4 10 3 1 29 55 4 39 8 - 92 0 0 2 41 56 9 0 8 24 116 -50 1 36 29 3 47 42 1 7 46 4 16 45 - 91 0 0 2 19 55 9 0 10 25 116 -49 1 14 32 3 25 35 0 45 52 3 54 36 - 90 0 0 1 58 8 9 0 12 26 116 -48 0 52 51 3 3 44 0 24 13 3 32 42 - 89 0 0 1 36 37 9 0 14 27 116 -47 0 31 25 2 42 7 0 2 49 3 11 3 - 88 0 0 1 15 21 9 0 17 28 116 -46 0 10 15 2 20 46 - 0 18 18 2 49 39 - 87 0 0 0 54 22 9 0 19 29 117 -45 - 0 10 39 1 59 41 - 0 39 10 2 28 32 - 86 0 0 0 33 40 9 0 22 30 117 -44 - 0 31 16 1 38 53 - 0 59 44 2 7 42 - 85 0 0 0 13 14 9 0 24 31 117 -43 - 0 51 36 1 18 22 - 1 20 2 1 47 8 - 84 0 0 - 0 6 54 9 0 27 32 117 -41 - 1 11 38 0 58 9 - 1 40 2 1 26 52 - 83 0 0 - 0 26 44 9 0 30 33 117 -40 - 1 31 22 0 38 13 - 1 59 44 1 6 54 - 82 0 0 - 0 46 15 9 0 32 34 117 -39 - 1 50 48 0 18 36 - 2 19 7 0 47 14 - 81 0 0 - 1 5 28 9 0 35 35 117 -38 - 2 9 56 - 0 0 43 - 2 38 12 0 27 53 - 80 0 0 - 1 24 22 9 0 38 36 117 -37 - 2 28 44 - 0 19 43 - 2 56 57 0 8 50 - 79 0 0 - 1 42 57 9 0 41 37 117 -36 - 2 47 13 - 0 38 23 - 3 15 24 - 0 9 52 - 78 0 0 - 2 1 11 9 0 44 38 117 -35 - 3 5 22 - 0 56 44 - 3 33 30 - 0 28 16 - 77 0 0 - 2 19 6 9 0 47 39 118 -34 - 3 23 10 - 1 14 44 - 3 51 17 - 0 46 19 - 76 0 0 - 2 36 40 9 0 50 40 118 -33 - 3 40 39 - 1 32 24 - 4 8 43 - 1 4 1 - 75 0 0 - 2 53 54 9 0 54 41 118 -32 - 3 57 47 - 1 49 43 - 4 25 48 - 1 21 23 - 74 0 0 - 3 10 47 9 0 57 43 118 -31 - 4 14 34 - 2 6 42 - 4 42 33 - 1 38 24 - 73 0 0 - 3 27 18 9 1 0 44 118 -30 - 4 31 0 - 2 23 19 - 4 58 56 - 1 55 3 - 72 0 0 - 3 43 28 9 1 4 45 118 -29 - 4 47 4 - 2 39 34 - 5 14 58 - 2 11 21 - 71 0 0 - 3 59 16 9 1 7 46 119 -28 - 5 2 47 - 2 55 28 - 5 30 38 - 2 27 17 - 70 0 0 - 4 14 42 9 1 11 47 119 -27 - 5 18 7 - 3 10 59 - 5 45 56 - 2 42 51 - 69 0 0 - 4 29 46 9 1 15 48 119 -26 - 5 33 6 - 3 26 8 - 6 0 52 - 2 58 3 - 68 0 0 - 4 44 27 9 1 18 49 119 -25 - 5 47 42 - 3 40 55 - 6 15 26 - 3 12 52 - 67 0 0 - 4 58 46 9 1 22 50 119 -24 - 6 1 55 - 3 55 19 - 6 29 37 - 3 27 18 - 66 0 0 - 5 12 41 9 1 26 51 120 -23 - 6 15 45 - 4 9 20 - 6 43 26 - 3 41 22 - 65 0 0 - 5 26 14 9 1 29 52 120 -22 - 6 29 13 - 4 22 58 - 6 56 51 - 3 55 2 - 64 0 0 - 5 39 23 9 1 33 53 120 -21 - 6 42 18 - 4 36 12 - 7 9 53 - 4 8 18 - 63 0 0 - 5 52 9 9 1 37 54 121 -20 - 6 54 59 - 4 49 3 - 7 22 32 - 4 21 11 - 62 0 0 - 6 4 32 9 1 41 55 121 -19 - 7 7 16 - 5 1 30 - 7 34 48 - 4 33 41 - 61 0 0 - 6 16 30 9 1 45 55 121 -18 - 7 19 10 - 5 13 33 - 7 46 40 - 4 45 46 - 60 0 0 - 6 28 5 9 1 49 56 122 -17 - 7 30 40 - 5 25 13 - 7 58 8 - 4 57 27 - 59 0 0 - 6 39 16 9 1 53 57 122 -15 - 7 41 47 - 5 36 28 - 8 9 12 - 5 8 44 - 58 0 0 - 6 50 2 9 1 57 58 123 -14 - 7 52 29 - 5 47 19 - 8 19 52 - 5 19 37 - 57 0 0 - 7 0 24 9 2 1 59 123 -13 - 8 2 47 - 5 57 45 - 8 30 9 - 5 30 5 - 56 0 0 - 7 10 22 9 2 6 60 124 -12 - 8 12 41 - 6 7 47 - 8 40 1 - 5 40 9 - 55 0 0 - 7 19 55 9 2 10 61 125 -11 - 8 22 10 - 6 17 24 - 8 49 29 - 5 49 48 - 54 0 0 - 7 29 4 9 2 14 62 125 -10 - 8 31 15 - 6 26 37 - 8 58 32 - 5 59 2 - 53 0 0 - 7 37 48 9 2 18 63 126 -9 - 8 39 56 - 6 35 24 - 9 7 11 - 6 7 51 - 52 0 0 - 7 46 7 9 2 23 64 127 -8 - 8 48 11 - 6 43 47 - 9 15 25 - 6 16 16 - 51 0 0 - 7 54 2 9 2 27 65 128 -7 - 8 56 2 - 6 51 45 - 9 23 15 - 6 24 15 - 50 0 0 - 8 1 31 9 2 31 66 129 -6 - 9 3 29 - 6 59 17 - 9 30 39 - 6 31 49 - 49 0 0 - 8 8 35 9 2 36 66 130 -5 - 9 10 30 - 7 6 24 - 9 37 39 - 6 38 57 - 48 0 0 - 8 15 15 9 2 40 67 131 -4 - 9 17 6 - 7 13 7 - 9 44 15 - 6 45 41 - 47 0 0 - 8 21 29 9 2 44 68 132 -3 - 9 23 18 - 7 19 23 - 9 50 25 - 6 51 59 - 46 0 0 - 8 27 18 9 2 49 69 134 -2 - 9 29 4 - 7 25 15 - 9 56 10 - 6 57 51 - 45 0 0 - 8 32 41 9 2 53 70 135 -1 - 9 34 26 - 7 30 41 -10 1 31 - 7 3 18 - 44 0 0 - 8 37 39 9 2 58 70 137 0 - 9 39 22 - 7 35 41 -10 6 26 - 7 8 19 Uncertainty in time = +/- 2 secs [Prediction of 2008 Feb 27.0] Data for the target star ------------------------ * name: 2UCAC 22754721 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 17 53 34.4091 DE: -22 31 02.517 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .023, .023 ) * V mag [mag]: 12.0 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (19) Fortuna approx. diameter [km]: 221 approx. diameter ["]: .108 distance from Earth [AU]: 2.81200 * orbital information: orbit source: Preston date of fit: 2008 Feb 27 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1551 number of rejected observations: 256 time covered by the observations: 1900 Feb 12 - 2007 Jul 25 1 sigma uncertainty ellipse (major, minor, PA): 0.008, 0.006, 90° remarks: * orbital elements for (19) Fortuna : Mean anomaly = 226.23600170 deg Arg. of pericenter = 181.86239944 deg Long. of node = 211.36173491 deg Inclination = 1.57295950 deg Eccentricity = 0.15868587 Semimajor axis = 2.44257244 AU Perihelion dist = 2.05497070 AU Mag: H = 7.13, G = 0.10 Epoch of elements : MJD 54529.37800000 TDT (2008 Mar 04.378) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Mar 4 19 Fortuna 9h 4.0m UT 12.0 17 53 34.409-22 31 2.522UCAC 22754721 0.0 12.6 221 9.1 2.812 3.091 0.82 -30.1098 -22.517 46.92 -6.23 9.0669 -0.00405 0.23396 13.69787 0.26266 -0.00567 0.00009 2000 223.8147332008 224.00000181.862399211.361735 1.5729600.15868587 2.4425724 2.0549707 7.1 5.00.10 RATE 2.5818610 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.024 0.024 90 1.22 0.024 0 54523.5020080304_754721 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Feb 27, 19:31 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org