IOTA/IOTA-ES occultation update for (542) Susanna / TYC 5239-00139-1 event on 2008 May 04, 18:49 UT Visible from Australia Summary ------- On 2008 May 04 UT, the 42 km diameter asteroid (542) Susanna will occult a 9.3 mag star in the constellation Aquarius for observers along a path across Australia. In the case of an occultation, the combined light of the asteroid and the star will drop by 5.4 mag to 14.7 mag (the magnitude of the asteroid) for at most 1.4 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: 62 * date and approx. time of event: 2008 May 04, 18:45 - 2008 May 04, 18:47 UT * midpoint of event [JD]: 2454591.28405417 * magnitude of target star: 9.3 * magnitude drop [mag]: 5.4 * estimated maximum duration [s]: 1.4 * Moon: 1 % sunlit, 56° distance * Sun: 66° distance * rough path description: Australia The occultation path -------------------- * approximate projected width [km]: 43 * 1 sigma uncertainty interval [path widths]: +/- 0.99 * 1 sigma uncertainty interval [seconds]: +/- 1.5 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .023 +/- .020) * 1 sigma uncertainty ellipse (major, minor, PA): ( .023", .020", 86° ) * approx speed of asteroid's shadow [km/s]: 30.5293 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5239-00139-1 by 542 Susanna on 2008 May 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 102 0 0 -28 6 15 18 45 38 1 96 -65 -28 17 56 -27 54 34 -28 41 6 -27 31 28 103 0 0 -28 11 55 18 45 38 1 96 -64 -28 23 36 -28 0 15 -28 46 45 -27 37 9 104 0 0 -28 17 19 18 45 38 2 95 -63 -28 28 59 -28 5 39 -28 52 8 -27 42 34 105 0 0 -28 22 26 18 45 38 3 95 -62 -28 34 6 -28 10 46 -28 57 14 -27 47 42 106 0 0 -28 27 16 18 45 38 4 94 -61 -28 38 56 -28 15 37 -29 2 3 -27 52 34 107 0 0 -28 31 50 18 45 38 5 94 -60 -28 43 30 -28 20 11 -29 6 36 -27 57 9 108 0 0 -28 36 7 18 45 39 6 93 -60 -28 47 47 -28 24 29 -29 10 52 -28 1 27 109 0 0 -28 40 8 18 45 39 7 93 -59 -28 51 47 -28 28 30 -29 14 52 -28 5 28 110 0 0 -28 43 52 18 45 40 8 92 -58 -28 55 30 -28 32 14 -29 18 35 -28 9 13 111 0 0 -28 47 19 18 45 40 9 92 -57 -28 58 57 -28 35 41 -29 22 1 -28 12 40 112 0 0 -28 50 29 18 45 40 9 91 -56 -29 2 7 -28 38 51 -29 25 11 -28 15 51 113 0 0 -28 53 22 18 45 41 10 91 -55 -29 5 0 -28 41 45 -29 28 3 -28 18 45 114 0 0 -28 55 59 18 45 42 11 90 -54 -29 7 37 -28 44 22 -29 30 39 -28 21 23 115 0 0 -28 58 19 18 45 42 12 90 -53 -29 9 56 -28 46 42 -29 32 59 -28 23 43 116 0 0 -29 0 21 18 45 43 13 89 -53 -29 11 59 -28 48 45 -29 35 1 -28 25 46 117 0 0 -29 2 7 18 45 44 14 89 -52 -29 13 45 -28 50 31 -29 36 46 -28 27 32 118 0 0 -29 3 36 18 45 45 15 88 -51 -29 15 13 -28 52 0 -29 38 15 -28 29 2 119 0 0 -29 4 48 18 45 45 16 88 -50 -29 16 25 -28 53 12 -29 39 27 -28 30 14 120 0 0 -29 5 44 18 45 46 16 87 -49 -29 17 20 -28 54 7 -29 40 22 -28 31 9 121 0 0 -29 6 22 18 45 47 17 87 -48 -29 17 59 -28 54 45 -29 41 0 -28 31 48 122 0 0 -29 6 43 18 45 48 18 86 -47 -29 18 20 -28 55 6 -29 41 21 -28 32 9 123 0 0 -29 6 47 18 45 49 19 86 -47 -29 18 24 -28 55 11 -29 41 25 -28 32 13 124 0 0 -29 6 34 18 45 50 20 85 -46 -29 18 11 -28 54 58 -29 41 12 -28 32 0 125 0 0 -29 6 4 18 45 52 21 85 -45 -29 17 41 -28 54 28 -29 40 42 -28 31 30 126 0 0 -29 5 17 18 45 53 22 84 -44 -29 16 54 -28 53 41 -29 39 55 -28 30 43 127 0 0 -29 4 13 18 45 54 23 84 -43 -29 15 50 -28 52 37 -29 38 52 -28 29 39 128 0 0 -29 2 52 18 45 55 23 83 -42 -29 14 29 -28 51 16 -29 37 31 -28 28 18 129 0 0 -29 1 14 18 45 57 24 83 -41 -29 12 51 -28 49 37 -29 35 53 -28 26 39 130 0 0 -28 59 19 18 45 58 25 82 -40 -29 10 56 -28 47 42 -29 33 58 -28 24 44 131 0 0 -28 57 7 18 45 59 26 82 -40 -29 8 44 -28 45 30 -29 31 47 -28 22 31 132 0 0 -28 54 38 18 46 1 27 81 -39 -29 6 15 -28 43 1 -29 29 18 -28 20 2 133 0 0 -28 51 52 18 46 2 28 81 -38 -29 3 29 -28 40 14 -29 26 32 -28 17 15 134 0 0 -28 48 48 18 46 4 29 80 -37 -29 0 26 -28 37 11 -29 23 30 -28 14 11 135 0 0 -28 45 28 18 46 6 30 80 -36 -28 57 6 -28 33 50 -29 20 10 -28 10 50 136 0 0 -28 41 51 18 46 7 30 79 -35 -28 53 29 -28 30 13 -29 16 34 -28 7 12 137 0 0 -28 37 56 18 46 9 31 79 -34 -28 49 35 -28 26 18 -29 12 40 -28 3 17 138 0 0 -28 33 45 18 46 11 32 78 -33 -28 45 24 -28 22 7 -29 8 30 -27 59 5 139 0 0 -28 29 17 18 46 12 33 77 -32 -28 40 56 -28 17 38 -29 4 2 -27 54 36 140 0 0 -28 24 32 18 46 14 34 77 -32 -28 36 11 -28 12 52 -28 59 18 -27 49 49 141 0 0 -28 19 30 18 46 16 35 76 -31 -28 31 10 -28 7 50 -28 54 17 -27 44 46 142 0 0 -28 14 10 18 46 18 36 76 -30 -28 25 51 -28 2 30 -28 48 59 -27 39 26 143 0 0 -28 8 34 18 46 20 37 75 -29 -28 20 15 -27 56 54 -28 43 24 -27 33 49 144 0 0 -28 2 42 18 46 22 38 75 -28 -28 14 23 -27 51 1 -28 37 33 -27 27 55 145 0 0 -27 56 32 18 46 24 38 74 -27 -28 8 13 -27 44 51 -28 31 24 -27 21 44 146 0 0 -27 50 5 18 46 26 39 73 -26 -28 1 47 -27 38 24 -28 24 59 -27 15 16 147 0 0 -27 43 22 18 46 28 40 73 -25 -27 55 5 -27 31 40 -28 18 17 -27 8 31 148 0 0 -27 36 22 18 46 30 41 72 -24 -27 48 5 -27 24 40 -28 11 18 -27 1 30 149 0 0 -27 29 5 18 46 33 42 72 -24 -27 40 49 -27 17 22 -28 4 3 -26 54 12 150 0 0 -27 21 32 18 46 35 43 71 -23 -27 33 16 -27 9 49 -27 56 31 -26 46 37 151 0 0 -27 13 42 18 46 37 44 70 -22 -27 25 26 -27 1 58 -27 48 43 -26 38 46 152 0 0 -27 5 36 18 46 40 45 70 -21 -27 17 20 -26 53 51 -27 40 38 -26 30 38 153 0 0 -26 57 13 18 46 42 46 69 -20 -27 8 58 -26 45 27 -27 32 16 -26 22 13 154 0 0 -26 48 33 18 46 45 46 68 -19 -27 0 19 -26 36 48 -27 23 39 -26 13 32 155 0 0 -26 39 37 18 46 47 47 68 -18 -26 51 24 -26 27 51 -27 14 44 -26 4 34 156 0 0 -26 30 25 18 46 50 48 67 -17 -26 42 12 -26 18 39 -27 5 34 -25 55 21 157 0 0 -26 20 57 18 46 52 49 66 -16 -26 32 45 -26 9 10 -26 56 8 -25 45 51 158 0 0 -26 11 12 18 46 55 50 66 -15 -26 23 1 -25 59 25 -26 46 25 -25 36 4 159 0 0 -26 1 12 18 46 57 51 65 -14 -26 13 1 -25 49 23 -26 36 26 -25 26 2 160 0 0 -25 50 55 18 47 0 52 64 -13 -26 2 45 -25 39 6 -26 26 11 -25 15 44 161 0 0 -25 40 23 18 47 3 53 63 -13 -25 52 13 -25 28 33 -26 15 41 -25 5 10 162 0 0 -25 29 35 18 47 6 54 63 -12 -25 41 26 -25 17 45 -26 4 55 -24 54 20 163 0 0 -25 18 31 18 47 8 54 62 -11 -25 30 23 -25 6 40 -25 53 53 -24 43 14 164 0 0 -25 7 12 18 47 11 55 61 -10 -25 19 4 -24 55 20 -25 42 35 -24 31 53 165 0 0 -24 55 37 18 47 14 56 60 -9 -25 7 30 -24 43 45 -25 31 2 -24 20 16 166 0 0 -24 43 47 18 47 17 57 59 -8 -24 55 40 -24 31 54 -25 19 14 -24 8 24 167 0 0 -24 31 42 18 47 20 58 58 -7 -24 43 36 -24 19 48 -25 7 11 -23 56 17 168 0 0 -24 19 21 18 47 23 59 58 -6 -24 31 16 -24 7 27 -24 54 52 -23 43 54 169 0 0 -24 6 46 18 47 26 60 57 -5 -24 18 41 -23 54 51 -24 42 19 -23 31 17 170 0 0 -23 53 56 18 47 29 61 56 -4 -24 5 52 -23 42 0 -24 29 31 -23 18 25 171 0 0 -23 40 51 18 47 32 62 55 -3 -23 52 48 -23 28 55 -24 16 28 -23 5 18 172 0 0 -23 27 32 18 47 35 62 53 -2 -23 39 29 -23 15 35 -24 3 11 -22 51 57 173 0 0 -23 13 59 18 47 38 63 52 -1 -23 25 57 -23 2 1 -23 49 40 -22 38 22 174 0 0 -23 0 11 18 47 42 64 51 0 -23 12 10 -22 48 13 -23 35 54 -22 24 32 Uncertainty in time = +/- 2 secs [Prediction of 2008 Mar 31.0] Data for the target star ------------------------ * name: TYC 5239-00139-1 * constellation : Aquarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 22 34 40.8558 DE: -05 42 24.876 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .017, .018 ) * V mag [mag]: 9.3 * B mag [mag]: 9.8 * Apparent position with proper motion RA(deg): 338.7790820817 DE(deg): -5.6646329621 * Equation of equinoxes (radians) : 0.000037771587542 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (542) Susanna approx. diameter [km]: 42 approx. diameter ["]: .020 distance from Earth [AU]: 2.85400 * orbital information: orbit source: Preston date of fit: 2008 Mar 28 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 832 number of rejected observations: 61 time covered by the observations: 1904 Aug 17 - 2007 Oct 09 1 sigma uncertainty ellipse (major, minor, PA): 0.016, 0.009, 81° remarks: * orbital elements for (542) Susanna : Mean anomaly = 321.00248072 deg Arg. of pericenter = 214.55519586 deg Long. of node = 153.06227252 deg Inclination = 12.07413168 deg Eccentricity = 0.13899692 Semimajor axis = 2.90703872 AU Perihelion dist = 2.50296930 AU Mag: H = 9.26, G = 0.15 Epoch of elements : MJD 54590.78400000 TDT (2008 May 04.784) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 4 542 Susanna 18h 49.0m UT 9.3 22 34 40.856- 5 42 24.88TYC 5239-00139-1 9.8 14.7 42 1.4 2.854 3.411 15.07 -166.6142 -5.711 -103.08 16.24 18.8173 0.05742 -0.19147 16.52286 4.89103 -0.00482 -0.00180 2000 320.8465822008 5 4.00000214.555196153.062273 12.0741320.13899692 2.9070387 2.5029693 9.4 5.00.15 RATE 1.9885100 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.023 0.020 86 1.99 0.020 0 54556.5020080504_0139-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 31, 03:54 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org