IOTA/IOTA-ES occultation update for (1310) Villigera / HIP 106067 event on 2008 Mar 25, 20:59 UT Visible from Indonesia Summary ------- On 2008 Mar 25 UT, the 17 km diameter asteroid (1310) Villigera will occult a 6.5 mag star in the constellation Piscis Austrinus for observers along a path across Indonesia. In the case of an occultation, the combined light of the asteroid and the star will drop by 10.9 mag to 17.4 mag (the magnitude of the asteroid) for at most 0.5 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: . The event at a glimpse ---------------------- * Rank: 24 * date and approx. time of event: 2008 Mar 25, 20:56 - 2008 Mar 25, 20:57 UT * midpoint of event [JD]: 2454551.37484583 * magnitude of target star: 6.5 * magnitude drop [mag]: 10.9 * estimated maximum duration [s]: 0.5 * Moon: 85 % sunlit, 83° distance * Sun: 53° distance * rough path description: Indonesia The occultation path -------------------- * approximate projected width [km]: 18 * 1 sigma uncertainty interval [path widths]: +/- 2.79 * 1 sigma uncertainty interval [seconds]: +/- 2.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .033 +/- .023) * 1 sigma uncertainty ellipse (major, minor, PA): ( .036", .018", 64° ) * approx speed of asteroid's shadow [km/s]: 33.5849 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of HIP 106067 by 1310 Villigera on 2008 Mar 25 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 96 0 0 2 16 51 20 56 46 0 121 -41 2 11 12 2 22 31 .. .. .. .. .. .. 97 0 0 1 40 32 20 56 46 1 121 -40 1 34 54 1 46 10 .. .. .. 2 17 42 98 0 0 1 4 41 20 56 46 2 121 -39 0 59 4 1 10 18 .. .. .. 1 41 43 99 0 0 0 29 19 20 56 46 4 121 -38 0 23 44 0 34 55 - 0 7 26 1 6 14 100 0 0 - 0 5 32 20 56 47 5 121 -37 - 0 11 6 0 0 3 - 0 42 10 0 31 14 101 0 0 - 0 39 52 20 56 47 6 121 -36 - 0 45 25 - 0 34 19 - 1 16 22 - 0 3 14 102 0 0 - 1 13 40 20 56 48 7 121 -35 - 1 19 13 - 1 8 8 - 1 50 2 - 0 37 11 103 0 0 - 1 46 56 20 56 48 8 121 -34 - 1 52 27 - 1 41 25 - 2 23 10 - 1 10 35 104 0 0 - 2 19 39 20 56 49 9 121 -33 - 2 25 9 - 2 14 10 - 2 55 45 - 1 43 26 105 0 0 - 2 51 49 20 56 49 10 121 -32 - 2 57 17 - 2 46 20 - 3 27 46 - 2 15 44 106 0 0 - 3 23 24 20 56 50 12 121 -31 - 3 28 51 - 3 17 57 - 3 59 13 - 2 47 27 107 0 0 - 3 54 24 20 56 51 13 121 -30 - 3 59 50 - 3 48 58 - 4 30 5 - 3 18 36 108 0 0 - 4 24 50 20 56 52 14 121 -29 - 4 30 15 - 4 19 25 - 5 0 23 - 3 49 9 109 0 0 - 4 54 40 20 56 53 15 121 -28 - 5 0 3 - 4 49 16 - 5 30 4 - 4 19 7 110 0 0 - 5 23 54 20 56 54 16 121 -27 - 5 29 16 - 5 18 31 - 5 59 10 - 4 48 29 111 0 0 - 5 52 31 20 56 55 17 121 -26 - 5 57 52 - 5 47 10 - 6 27 40 - 5 17 15 112 0 0 - 6 20 33 20 56 56 18 121 -25 - 6 25 52 - 6 15 13 - 6 55 33 - 5 45 24 113 0 0 - 6 47 57 20 56 57 19 121 -24 - 6 53 15 - 6 42 38 - 7 22 50 - 6 12 56 114 0 0 - 7 14 44 20 56 59 20 121 -23 - 7 20 1 - 7 9 26 - 7 49 29 - 6 39 51 115 0 0 - 7 40 54 20 57 0 21 121 -22 - 7 46 10 - 7 35 37 - 8 15 32 - 7 6 9 116 0 0 - 8 6 26 20 57 1 23 121 -21 - 8 11 41 - 8 1 11 - 8 40 57 - 7 31 48 117 0 0 - 8 31 21 20 57 3 24 120 -20 - 8 36 35 - 8 26 7 - 9 5 44 - 7 56 50 118 0 0 - 8 55 38 20 57 4 25 120 -19 - 9 0 50 - 8 50 24 - 9 29 53 - 8 21 15 119 0 0 - 9 19 16 20 57 6 26 120 -18 - 9 24 28 - 9 14 4 - 9 53 25 - 8 45 1 120 0 0 - 9 42 17 20 57 8 27 120 -17 - 9 47 28 - 9 37 6 -10 16 19 - 9 8 8 121 0 0 -10 4 40 20 57 9 28 120 -16 -10 9 50 - 9 59 30 -10 38 35 - 9 30 38 122 0 0 -10 26 24 20 57 11 29 120 -15 -10 31 33 -10 21 15 -11 0 13 - 9 52 29 123 0 0 -10 47 31 20 57 13 30 120 -14 -10 52 38 -10 42 23 -11 21 12 -10 13 42 124 0 0 -11 7 59 20 57 15 31 120 -13 -11 13 5 -11 2 52 -11 41 34 -10 34 17 125 0 0 -11 27 48 20 57 17 32 120 -12 -11 32 54 -11 22 42 -12 1 17 -10 54 13 126 0 0 -11 47 0 20 57 19 33 120 -11 -11 52 5 -11 41 55 -12 20 23 -11 13 30 127 0 0 -12 5 33 20 57 21 34 120 -10 -12 10 37 -12 0 29 -12 38 50 -11 32 9 128 0 0 -12 23 28 20 57 23 35 120 -9 -12 28 31 -12 18 25 -12 56 39 -11 50 10 129 0 0 -12 40 45 20 57 25 36 120 -8 -12 45 47 -12 35 42 -13 13 50 -12 7 33 130 0 0 -12 57 23 20 57 27 37 120 -7 -13 2 25 -12 52 22 -13 30 24 -12 24 17 131 0 0 -13 13 24 20 57 29 38 120 -6 -13 18 24 -13 8 23 -13 46 19 -12 40 22 132 0 0 -13 28 46 20 57 31 39 119 -5 -13 33 46 -13 23 46 -14 1 36 -12 55 50 133 0 0 -13 43 31 20 57 33 40 119 -4 -13 48 30 -13 38 31 -14 16 16 -13 10 39 134 0 0 -13 57 37 20 57 36 41 119 -3 -14 2 36 -13 52 39 -14 30 18 -13 24 50 135 0 0 -14 11 6 20 57 38 42 119 -3 -14 16 3 -14 6 8 -14 43 42 -13 38 24 136 0 0 -14 23 57 20 57 40 43 120 -2 -14 28 54 -14 18 59 -14 56 28 -13 51 19 137 0 0 -14 36 10 20 57 43 44 120 -1 -14 41 6 -14 31 13 -15 8 37 -14 3 36 Uncertainty in time = +/- 3 secs [Prediction of 2008 Feb 14.0] Data for the target star ------------------------ * name: HIP 106067 * constellation : Piscis Austrinus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 21 29 03.7520 DE: -31 14 18.903 * position source: mpos:HIP pm:HIP plx:HIP * standard error: RA,DE ["]: ( .015, .007 ) * V mag [mag]: 6.5 * B mag [mag]: 6.6 * Apparent position with proper motion RA(deg): 322.3873478481 DE(deg): -31.2029853840 * Equation of equinoxes (radians) : 0.000040630514329 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1310) Villigera approx. diameter [km]: 17 approx. diameter ["]: .007 distance from Earth [AU]: 3.50600 * orbital information: orbit source: Preston date of fit: 2007 Nov 02 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 461 number of rejected observations: 38 time covered by the observations: 1932 Feb 28 - 2006 Jun 29 1 sigma uncertainty ellipse (major, minor, PA): 0.033, 0.017, 59° remarks: * orbital elements for (1310) Villigera : Mean anomaly = 238.07665178 deg Arg. of pericenter = 88.58262057 deg Long. of node = 357.39638582 deg Inclination = 21.06427815 deg Eccentricity = 0.35486839 Semimajor axis = 2.39379553 AU Perihelion dist = 1.54431316 AU Mag: H = 11.39, G = 0.15 Epoch of elements : MJD 54550.87500000 TDT (2008 Mar 25.875) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Mar 25 1310 Villigera 20h 59.8m UT 6.5 21 29 3.752-31 14 18.90HIP 106067 6.6 17.4 17 0.5 3.506 3.577 12.54 -176.3673 -31.242 -133.50 2.22 20.9963 -0.08143 0.29813 18.28513 4.99942 -0.00393 -0.00240 2000 237.8437992008 325.00000 88.582621357.396386 21.0642780.35486839 2.3937955 1.544313211.5 5.00.15 RATE 2.6611760 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.036 0.018 64 3.79 0.019 0 54510.5020080325_106067 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Feb 14, 19:41 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org