IOTA/IOTA-ES occultation update for (50) Virginia / TYC 5240-01105-1 event on 2008 May 12, 19:19 UT Visible from Australia Summary ------- On 2008 May 12 UT, the 100 km diameter asteroid (50) Virginia will occult a 10.4 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 3.4 mag to 13.8 mag (the magnitude of the asteroid) for at most 3.2 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: 96 * date and approx. time of event: 2008 May 12, 19:15 - 2008 May 12, 19:18 UT * midpoint of event [JD]: 2454599.30499167 * magnitude of target star: 10.4 * magnitude drop [mag]: 3.4 * estimated maximum duration [s]: 3.2 * Moon: 58 % sunlit, 171° distance * Sun: 72° distance * rough path description: Australia The occultation path -------------------- * approximate projected width [km]: 101 * 1 sigma uncertainty interval [path widths]: +/- 0.41 * 1 sigma uncertainty interval [seconds]: +/- 1.5 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .028 +/- .025) * 1 sigma uncertainty ellipse (major, minor, PA): ( .028", .025", 79° ) * approx speed of asteroid's shadow [km/s]: 30.7297 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5240-01105-1 by 50 Virginia on 2008 May 12 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 88 0 0 -27 44 46 19 15 45 0 97 -71 -28 12 13 -27 17 20 -28 34 45 -26 54 51 89 0 0 -27 51 2 19 15 45 1 96 -70 -28 18 27 -27 23 37 -28 40 58 -27 1 9 90 0 0 -27 56 56 19 15 45 2 96 -69 -28 24 21 -27 29 33 -28 46 51 -27 7 6 91 0 0 -28 2 30 19 15 45 3 95 -69 -28 29 53 -27 35 8 -28 52 22 -27 12 42 92 0 0 -28 7 42 19 15 45 4 95 -68 -28 35 5 -27 40 21 -28 57 33 -27 17 56 93 0 0 -28 12 34 19 15 46 5 95 -67 -28 39 55 -27 45 13 -29 2 22 -27 22 50 94 0 0 -28 17 4 19 15 46 6 94 -66 -28 44 24 -27 49 44 -29 6 50 -27 27 21 95 0 0 -28 21 12 19 15 46 6 94 -65 -28 48 32 -27 53 54 -29 10 58 -27 31 32 96 0 0 -28 25 0 19 15 47 7 93 -64 -28 52 19 -27 57 43 -29 14 44 -27 35 21 97 0 0 -28 28 26 19 15 47 8 93 -63 -28 55 45 -28 1 10 -29 18 9 -27 38 48 98 0 0 -28 31 32 19 15 48 9 92 -63 -28 58 49 -28 4 15 -29 21 13 -27 41 55 99 0 0 -28 34 15 19 15 48 10 92 -62 -29 1 32 -28 7 0 -29 23 56 -27 44 40 100 0 0 -28 36 38 19 15 49 11 91 -61 -29 3 54 -28 9 23 -29 26 17 -27 47 3 101 0 0 -28 38 39 19 15 49 12 91 -60 -29 5 55 -28 11 25 -29 28 18 -27 49 5 102 0 0 -28 40 19 19 15 50 13 90 -59 -29 7 35 -28 13 5 -29 29 57 -27 50 46 103 0 0 -28 41 38 19 15 51 14 90 -58 -29 8 53 -28 14 24 -29 31 15 -27 52 5 104 0 0 -28 42 35 19 15 51 14 89 -57 -29 9 50 -28 15 21 -29 32 12 -27 53 3 105 0 0 -28 43 11 19 15 52 15 89 -57 -29 10 26 -28 15 57 -29 32 47 -27 53 39 106 0 0 -28 43 25 19 15 53 16 88 -56 -29 10 40 -28 16 12 -29 33 2 -27 53 53 107 0 0 -28 43 18 19 15 54 17 88 -55 -29 10 33 -28 16 5 -29 32 55 -27 53 46 108 0 0 -28 42 50 19 15 55 18 87 -54 -29 10 5 -28 15 37 -29 32 27 -27 53 18 109 0 0 -28 42 1 19 15 56 19 87 -53 -29 9 16 -28 14 47 -29 31 37 -27 52 28 110 0 0 -28 40 49 19 15 57 20 86 -52 -29 8 5 -28 13 35 -29 30 27 -27 51 17 111 0 0 -28 39 17 19 15 58 21 86 -51 -29 6 33 -28 12 3 -29 28 55 -27 49 43 112 0 0 -28 37 23 19 15 59 21 85 -50 -29 4 39 -28 10 8 -29 27 2 -27 47 49 113 0 0 -28 35 8 19 16 1 22 85 -50 -29 2 24 -28 7 52 -29 24 47 -27 45 33 114 0 0 -28 32 31 19 16 2 23 84 -49 -28 59 48 -28 5 15 -29 22 11 -27 42 55 115 0 0 -28 29 32 19 16 3 24 84 -48 -28 56 50 -28 2 16 -29 19 14 -27 39 55 116 0 0 -28 26 12 19 16 4 25 83 -47 -28 53 31 -27 58 56 -29 15 55 -27 36 34 117 0 0 -28 22 31 19 16 6 26 83 -46 -28 49 50 -27 55 13 -29 12 15 -27 32 51 118 0 0 -28 18 28 19 16 7 27 82 -45 -28 45 48 -27 51 10 -29 8 14 -27 28 47 119 0 0 -28 14 4 19 16 9 28 82 -44 -28 41 25 -27 46 44 -29 3 51 -27 24 21 120 0 0 -28 9 18 19 16 10 29 81 -43 -28 36 40 -27 41 58 -28 59 7 -27 19 33 121 0 0 -28 4 11 19 16 12 29 81 -42 -28 31 33 -27 36 49 -28 54 2 -27 14 24 122 0 0 -27 58 42 19 16 13 30 80 -42 -28 26 5 -27 31 19 -28 48 35 -27 8 53 123 0 0 -27 52 51 19 16 15 31 80 -41 -28 20 16 -27 25 27 -28 42 46 -27 3 0 124 0 0 -27 46 39 19 16 17 32 79 -40 -28 14 5 -27 19 14 -28 36 36 -26 56 46 125 0 0 -27 40 5 19 16 19 33 79 -39 -28 7 33 -27 12 39 -28 30 5 -26 50 10 126 0 0 -27 33 10 19 16 20 34 78 -38 -28 0 39 -27 5 42 -28 23 12 -26 43 12 127 0 0 -27 25 53 19 16 22 35 78 -37 -27 53 24 -26 58 24 -28 15 58 -26 35 52 128 0 0 -27 18 15 19 16 24 36 77 -36 -27 45 47 -26 50 44 -28 8 23 -26 28 11 129 0 0 -27 10 15 19 16 26 37 77 -35 -27 37 48 -26 42 42 -28 0 26 -26 20 8 130 0 0 -27 1 53 19 16 28 38 76 -34 -27 29 29 -26 34 19 -27 52 7 -26 11 44 131 0 0 -26 53 10 19 16 30 38 76 -33 -27 20 47 -26 25 35 -27 43 27 -26 2 58 132 0 0 -26 44 6 19 16 32 39 75 -33 -27 11 45 -26 16 28 -27 34 26 -25 53 50 133 0 0 -26 34 40 19 16 34 40 75 -32 -27 2 20 -26 7 0 -27 25 3 -25 44 21 134 0 0 -26 24 52 19 16 37 41 74 -31 -26 52 35 -25 57 11 -27 15 19 -25 34 30 135 0 0 -26 14 43 19 16 39 42 74 -30 -26 42 28 -25 47 0 -27 5 14 -25 24 17 136 0 0 -26 4 13 19 16 41 43 73 -29 -26 31 59 -25 36 27 -26 54 47 -25 13 43 137 0 0 -25 53 21 19 16 43 44 73 -28 -26 21 9 -25 25 34 -26 43 59 -25 2 47 138 0 0 -25 42 8 19 16 46 45 72 -27 -26 9 58 -25 14 18 -26 32 49 -24 51 30 139 0 0 -25 30 33 19 16 48 46 72 -26 -25 58 26 -25 2 42 -26 21 19 -24 39 52 140 0 0 -25 18 37 19 16 51 47 71 -25 -25 46 32 -24 50 44 -26 9 27 -24 27 52 141 0 0 -25 6 20 19 16 53 48 70 -24 -25 34 17 -24 38 24 -25 57 14 -24 15 31 142 0 0 -24 53 42 19 16 56 49 70 -23 -25 21 41 -24 25 44 -25 44 40 -24 2 49 143 0 0 -24 40 43 19 16 58 50 69 -22 -25 8 44 -24 12 42 -25 31 45 -23 49 45 144 0 0 -24 27 22 19 17 1 50 69 -21 -24 55 26 -23 59 20 -25 18 29 -23 36 21 145 0 0 -24 13 41 19 17 4 51 68 -20 -24 41 48 -23 45 36 -25 4 52 -23 22 35 146 0 0 -23 59 39 19 17 6 52 68 -20 -24 27 48 -23 31 32 -24 50 54 -23 8 29 147 0 0 -23 45 16 19 17 9 53 67 -19 -24 13 27 -23 17 6 -24 36 36 -22 54 2 148 0 0 -23 30 33 19 17 12 54 66 -18 -23 58 46 -23 2 20 -24 21 56 -22 39 14 149 0 0 -23 15 29 19 17 15 55 66 -17 -23 43 45 -22 47 14 -24 6 57 -22 24 5 150 0 0 -23 0 4 19 17 18 56 65 -16 -23 28 23 -22 31 47 -23 51 37 -22 8 36 151 0 0 -22 44 19 19 17 21 57 65 -15 -23 12 41 -22 16 0 -23 35 57 -21 52 47 152 0 0 -22 28 14 19 17 24 58 64 -14 -22 56 38 -21 59 52 -23 19 57 -21 36 37 153 0 0 -22 11 50 19 17 27 59 63 -13 -22 40 16 -21 43 25 -23 3 36 -21 20 8 154 0 0 -21 55 5 19 17 30 60 63 -12 -22 23 34 -21 26 38 -22 46 56 -21 3 19 155 0 0 -21 38 1 19 17 33 61 62 -11 -22 6 32 -21 9 31 -22 29 57 -20 46 10 156 0 0 -21 20 37 19 17 36 62 61 -10 -21 49 11 -20 52 4 -22 12 37 -20 28 41 157 0 0 -21 2 54 19 17 39 63 60 -9 -21 31 30 -20 34 19 -21 54 59 -20 10 54 158 0 0 -20 44 52 19 17 42 64 60 -8 -21 13 31 -20 16 14 -21 37 1 -19 52 47 159 0 0 -20 26 31 19 17 46 65 59 -7 -20 55 12 -19 57 51 -21 18 45 -19 34 21 160 0 0 -20 7 51 19 17 49 66 58 -6 -20 36 35 -19 39 9 -21 0 10 -19 15 37 161 0 0 -19 48 53 19 17 52 67 57 -5 -20 17 40 -19 20 8 -20 41 17 -18 56 35 162 0 0 -19 29 37 19 17 56 68 56 -4 -19 58 26 -19 0 50 -20 22 5 -18 37 14 163 0 0 -19 10 4 19 17 59 69 55 -3 -19 38 55 -18 41 14 -20 2 36 -18 17 36 164 0 0 -18 50 12 19 18 3 70 54 -2 -19 19 6 -18 21 20 -19 42 49 -17 57 41 165 0 0 -18 30 4 19 18 6 71 53 -1 -18 59 0 -18 1 9 -19 22 45 -17 37 28 Uncertainty in time = +/- 1 secs [Prediction of 2008 Mar 31.0] Data for the target star ------------------------ * name: TYC 5240-01105-1 * constellation : Aquarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 22 42 48.7039 DE: -06 13 58.581 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .019, .024 ) * V mag [mag]: 10.4 * B mag [mag]: 11.3 * Apparent position with proper motion RA(deg): 340.8127643958 DE(deg): -6.1895003190 * Equation of equinoxes (radians) : 0.000041144550371 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (50) Virginia approx. diameter [km]: 100 approx. diameter ["]: .062 distance from Earth [AU]: 2.21600 * orbital information: orbit source: Preston date of fit: 2008 Feb 16 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1194 number of rejected observations: 116 time covered by the observations: 1900 Sep 20 - 2007 Sep 13 1 sigma uncertainty ellipse (major, minor, PA): 0.021, 0.009, 71° remarks: * orbital elements for (50) Virginia : Mean anomaly = 324.73055636 deg Arg. of pericenter = 200.05221633 deg Long. of node = 173.63319616 deg Inclination = 2.83204663 deg Eccentricity = 0.28380901 Semimajor axis = 2.65192432 AU Perihelion dist = 1.89928430 AU Mag: H = 9.12, G = 0.15 Epoch of elements : MJD 54598.80500000 TDT (2008 May 12.805) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 12 50 Virginia 19h 19.2m UT 10.4 22 42 48.704- 6 13 58.58TYC 5240-01105-1 11.3 13.8 100 3.2 2.216 4.294 25.29 179.9757 -6.240 -110.71 18.38 19.3198 0.04054 -0.09958 16.13168 6.37233 -0.00469 -0.00185 2000 322.7210392008 5 4.00000200.052216173.633196 2.8320470.28380901 2.6519243 1.8992843 9.2 5.00.15 RATE 2.2822450 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.028 0.025 79 1.41 0.025 0 54556.5020080512_1105-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 31, 04:44 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org