IOTA/IOTA-ES occultation update for (1623) Vivian / TYC 6263-00069-1 event on 2008 Mar 27, 18:35 UT Visible from Japan, China Summary ------- On 2008 Mar 27 UT, the 34 km diameter asteroid (1623) Vivian will occult a 10.7 mag star in the constellation Sagittarius for observers along a path across Japan, China. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.6 mag to 17.3 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: 23 * date and approx. time of event: 2008 Mar 27, 18:28 - 2008 Mar 27, 18:35 UT * midpoint of event [JD]: 2454553.27404167 * magnitude of target star: 10.7 * magnitude drop [mag]: 6.6 * estimated maximum duration [s]: 3.2 * Moon: 70 % sunlit, 18° distance * Sun: 97° distance * rough path description: Japan, China The occultation path -------------------- * approximate projected width [km]: 60 * 1 sigma uncertainty interval [path widths]: +/- 2.88 * 1 sigma uncertainty interval [seconds]: +/- 8.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .039 +/- .040) * 1 sigma uncertainty ellipse (major, minor, PA): ( .040", .039", 0° ) * approx speed of asteroid's shadow [km/s]: 10.5299 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6263-00069-1 by 1623 Vivian 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 ' " Longitude Longitude Longitude Longitude Latitude Latitude Latitude Latitude 170 0 0 34 22 39 18 35 29 34 185 0 34 6 18 34 39 8 32 34 10 36 16 25 169 0 0 34 17 31 18 35 20 34 183 -1 34 1 10 34 33 58 32 29 8 36 11 8 168 0 0 34 12 59 18 35 11 34 182 -2 33 56 39 34 29 25 32 24 43 36 6 29 167 0 0 34 9 4 18 35 2 34 181 -3 33 52 45 34 25 30 32 20 53 36 2 28 166 0 0 34 5 46 18 34 52 34 180 -4 33 49 28 34 22 11 32 17 40 35 59 5 165 0 0 34 3 5 18 34 43 34 179 -5 33 46 48 34 19 29 32 15 3 35 56 20 164 0 0 34 1 1 18 34 34 34 178 -6 33 44 44 34 17 25 32 13 2 35 54 12 163 0 0 33 59 34 18 34 25 34 176 -6 33 43 18 34 15 58 32 11 37 35 52 43 162 0 0 33 58 44 18 34 16 34 175 -7 33 42 28 34 15 8 32 10 48 35 51 52 161 0 0 33 58 32 18 34 7 34 174 -8 33 42 15 34 14 55 32 10 36 35 51 38 160 0 0 33 58 56 18 33 58 34 173 -9 33 42 40 34 15 19 32 11 0 35 52 3 159 0 0 33 59 57 18 33 49 34 172 -10 33 43 41 34 16 21 32 12 0 35 53 6 158 0 0 34 1 36 18 33 40 34 171 -11 33 45 19 34 18 0 32 13 37 35 54 47 157 0 0 34 3 52 18 33 31 34 170 -11 33 47 34 34 20 16 32 15 50 35 57 6 156 0 0 34 6 44 18 33 22 33 168 -12 33 50 26 34 23 9 32 18 38 36 0 2 155 0 0 34 10 13 18 33 13 33 167 -13 33 53 55 34 26 39 32 22 3 36 3 37 154 0 0 34 14 20 18 33 4 33 166 -14 33 58 0 34 30 46 32 26 4 36 7 49 153 0 0 34 19 2 18 32 56 33 165 -15 34 2 42 34 35 30 32 30 41 36 12 39 152 0 0 34 24 22 18 32 47 32 164 -16 34 8 0 34 40 50 32 35 53 36 18 6 151 0 0 34 30 18 18 32 38 32 163 -16 34 13 55 34 46 47 32 41 42 36 24 11 150 0 0 34 36 50 18 32 30 32 162 -17 34 20 26 34 53 21 32 48 5 36 30 53 149 0 0 34 43 58 18 32 21 31 161 -18 34 27 32 35 0 30 32 55 4 36 38 12 148 0 0 34 51 42 18 32 13 31 160 -19 34 35 15 35 8 16 33 2 38 36 46 8 147 0 0 35 0 2 18 32 5 30 159 -19 34 43 33 35 16 38 33 10 47 36 54 40 146 0 0 35 8 58 18 31 57 30 158 -20 34 52 27 35 25 35 33 19 31 37 3 49 145 0 0 35 18 29 18 31 49 30 157 -21 35 1 56 35 35 8 33 28 50 37 13 35 144 0 0 35 28 35 18 31 41 29 156 -22 35 12 0 35 45 16 33 38 42 37 23 56 143 0 0 35 39 15 18 31 33 29 155 -22 35 22 39 35 56 0 33 49 9 37 34 53 142 0 0 35 50 31 18 31 26 28 154 -23 35 33 52 36 7 17 34 0 10 37 46 26 141 0 0 36 2 21 18 31 18 27 153 -24 35 45 39 36 19 10 34 11 44 37 58 34 140 0 0 36 14 45 18 31 11 27 152 -25 35 58 0 36 31 36 34 23 52 38 11 17 139 0 0 36 27 42 18 31 4 26 151 -25 36 10 55 36 44 36 34 36 32 38 24 34 138 0 0 36 41 13 18 30 57 26 150 -26 36 24 23 36 58 10 34 49 45 38 38 26 137 0 0 36 55 17 18 30 50 25 149 -26 36 38 24 37 12 17 35 3 30 38 52 52 136 0 0 37 9 53 18 30 43 24 148 -27 36 52 58 37 26 57 35 17 47 39 7 51 135 0 0 37 25 2 18 30 37 24 147 -28 37 8 3 37 42 9 35 32 36 39 23 23 134 0 0 37 40 43 18 30 30 23 146 -28 37 23 41 37 57 53 35 47 56 39 39 28 133 0 0 37 56 55 18 30 24 22 146 -29 37 39 49 38 14 8 36 3 46 39 56 5 132 0 0 38 13 38 18 30 18 22 145 -29 37 56 29 38 30 55 36 20 7 40 13 14 131 0 0 38 30 51 18 30 12 21 144 -30 38 13 39 38 48 12 36 36 58 40 30 54 130 0 0 38 48 35 18 30 7 20 143 -30 38 31 19 39 5 59 36 54 18 40 49 6 129 0 0 39 6 48 18 30 1 20 142 -31 38 49 28 39 24 16 37 12 7 41 7 47 128 0 0 39 25 30 18 29 56 19 142 -31 39 8 6 39 43 2 37 30 24 41 26 58 127 0 0 39 44 40 18 29 51 18 141 -32 39 27 12 40 2 17 37 49 9 41 46 39 126 0 0 40 4 19 18 29 46 17 140 -32 39 46 46 40 21 59 38 8 21 42 6 48 125 0 0 40 24 24 18 29 42 17 139 -33 40 6 48 40 42 9 38 28 0 42 27 25 124 0 0 40 44 57 18 29 37 16 138 -33 40 27 16 41 2 46 38 48 5 42 48 30 123 0 0 41 5 55 18 29 33 15 138 -33 40 48 10 41 23 49 39 8 36 43 10 1 122 0 0 41 27 19 18 29 29 14 137 -34 41 9 29 41 45 17 39 29 31 43 31 59 121 0 0 41 49 7 18 29 25 14 136 -34 41 31 13 42 7 11 39 50 51 43 54 22 120 0 0 42 11 20 18 29 22 13 135 -34 41 53 21 42 29 28 40 12 34 44 17 10 119 0 0 42 33 56 18 29 18 12 135 -35 42 15 52 42 52 9 40 34 40 44 40 21 118 0 0 42 56 54 18 29 15 11 134 -35 42 38 46 43 15 12 40 57 8 45 3 56 117 0 0 43 20 15 18 29 12 10 133 -35 43 2 1 43 38 37 41 19 58 45 27 53 116 0 0 43 43 56 18 29 10 10 132 -35 43 25 38 44 2 24 41 43 9 45 52 12 115 0 0 44 7 58 18 29 7 9 132 -35 43 49 34 44 26 31 42 6 39 46 16 52 114 0 0 44 32 19 18 29 5 8 131 -36 44 13 51 44 50 57 42 30 28 46 41 51 113 0 0 44 56 59 18 29 3 7 130 -36 44 38 25 45 15 42 42 54 36 47 7 10 112 0 0 45 21 56 18 29 1 6 130 -36 45 3 18 45 40 45 .. .. .. 47 32 47 111 0 0 45 47 11 18 29 0 5 129 -36 45 28 27 46 6 5 .. .. .. 47 58 41 110 0 0 46 12 41 18 28 58 5 128 -36 45 53 52 46 31 41 .. .. .. 48 24 51 109 0 0 46 38 27 18 28 57 4 127 -36 46 19 33 46 57 32 .. .. .. 48 51 17 108 0 0 47 4 27 18 28 56 3 127 -36 46 45 27 47 23 37 .. .. .. 49 17 57 107 0 0 47 30 40 18 28 56 2 126 -36 47 11 35 47 49 56 .. .. .. 49 44 51 106 0 0 47 57 5 18 28 55 1 125 -36 47 37 55 48 16 27 .. .. .. 50 11 57 105 0 0 48 23 42 18 28 55 1 124 -36 48 4 27 48 43 9 .. .. .. .. .. .. Uncertainty in time = +/- 9 secs [Prediction of 2008 Feb 14.0] Data for the target star ------------------------ * name: TYC 6263-00069-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 18 00 40.4433 DE: -21 40 12.290 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .023, .036 ) * V mag [mag]: 10.7 * B mag [mag]: 11.0 * Apparent position with proper motion RA(deg): 270.2956686380 DE(deg): -21.6722967516 * Equation of equinoxes (radians) : 0.000040763358931 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1623) Vivian approx. diameter [km]: 34 approx. diameter ["]: .014 distance from Earth [AU]: 3.39000 * orbital information: orbit source: Preston date of fit: 2008 Feb 13 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 943 number of rejected observations: 43 time covered by the observations: 1948 Aug 09 - 2007 Aug 15 1 sigma uncertainty ellipse (major, minor, PA): 0.031, 0.018, 92° remarks: * orbital elements for (1623) Vivian : Mean anomaly = 184.24487126 deg Arg. of pericenter = 315.59398193 deg Long. of node = 115.69885210 deg Inclination = 2.48916474 deg Eccentricity = 0.16283853 Semimajor axis = 3.14103121 AU Perihelion dist = 2.62955031 AU Mag: H = 11.27, G = 0.15 Epoch of elements : MJD 54552.77400000 TDT (2008 Mar 27.774) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Mar 27 1623 Vivian 18h 34.6m UT 10.7 18 0 40.443-21 40 12.29TYC 6263-00069-1 11.0 17.3 34 3.2 3.390 1.105 0.50 165.9536 -21.670 -97.36 2.96 18.5770 -0.02542 0.82333 5.94020 0.19361 -0.00587 -0.00003 2000 183.7537352008 325.00000315.593982115.698852 2.4891650.16283853 3.1410312 2.629550311.0 5.00.15 RATE 1.7704990 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.040 0.039 0 3.88 0.040 0 54510.5020080327_0069-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Feb 14, 19:58 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org