IOTA/IOTA-ES occultation update for (10) Hygiea / TYC 1813-01183-1 event on 2008 Jul 10, 19:16 UT Visible from Japan, S China Summary ------- On 2008 Jul 10 UT, the 407 km diameter asteroid (10) Hygiea will occult a 11.3 mag star in the constellation Taurus for observers along a path across Japan, S China. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.2 mag to 12.0 mag (the magnitude of the asteroid) for at most 11.7 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: 100 * date and approx. time of event: 2008 Jul 10, 19:14 - 2008 Jul 10, 19:14 UT * midpoint of event [JD]: 2454658.30325 * magnitude of target star: 11.3 * magnitude drop [mag]: 1.2 * estimated maximum duration [s]: 11.7 * Moon: 56 % sunlit, 142° distance * Sun: 46° distance * rough path description: Japan, S China The occultation path -------------------- * approximate projected width [km]: 490 * 1 sigma uncertainty interval [path widths]: +/- 0.13 * 1 sigma uncertainty interval [seconds]: +/- 1.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .021 +/- .018) * 1 sigma uncertainty ellipse (major, minor, PA): ( .021", .018", 89° ) * approx speed of asteroid's shadow [km/s]: 34.9400 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1813-01183-1 by 10 Hygiea on 2008 Jul 10 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 104 0 0 20 37 1 19 14 9 0 65 -38 .. .. .. 23 6 57 .. .. .. 23 46 47 105 0 0 21 3 40 19 14 9 1 66 -37 18 38 4 23 34 2 18 0 54 24 14 1 106 0 0 21 30 39 19 14 9 2 66 -36 19 4 39 24 1 28 18 27 23 24 41 34 107 0 0 21 57 58 19 14 10 3 66 -35 19 31 33 24 29 14 18 54 11 25 9 27 108 0 0 22 25 36 19 14 10 4 67 -34 19 58 46 24 57 18 19 21 19 25 37 38 109 0 0 22 53 31 19 14 10 5 67 -33 20 26 18 25 25 40 19 48 44 26 6 7 110 0 0 23 21 44 19 14 11 7 67 -32 20 54 7 25 54 18 20 16 28 26 34 53 111 0 0 23 50 13 19 14 11 8 68 -31 21 22 13 26 23 13 20 44 28 27 3 56 112 0 0 24 18 58 19 14 12 9 68 -30 21 50 35 26 52 24 21 12 44 27 33 13 113 0 0 24 47 58 19 14 12 10 69 -29 22 19 12 27 21 49 21 41 15 28 2 45 114 0 0 25 17 11 19 14 13 11 69 -28 22 48 3 27 51 27 22 10 1 28 32 30 115 0 0 25 46 38 19 14 14 12 70 -27 23 17 8 28 21 18 22 39 1 29 2 28 116 0 0 26 16 17 19 14 15 13 70 -26 23 46 26 28 51 21 23 8 13 29 32 37 117 0 0 26 46 8 19 14 16 14 71 -25 24 15 55 29 21 34 23 37 38 30 2 57 118 0 0 27 16 9 19 14 17 15 71 -24 24 45 36 29 51 58 24 7 13 30 33 27 119 0 0 27 46 19 19 14 18 16 72 -23 25 15 26 30 22 30 24 36 59 31 4 5 120 0 0 28 16 38 19 14 19 17 72 -22 25 45 26 30 53 10 25 6 54 31 34 51 121 0 0 28 47 4 19 14 20 18 73 -21 26 15 34 31 23 57 25 36 57 32 5 44 122 0 0 29 17 37 19 14 21 19 73 -20 26 45 49 31 54 49 26 7 8 32 36 42 123 0 0 29 48 16 19 14 22 20 74 -19 27 16 11 32 25 47 26 37 25 33 7 44 124 0 0 30 18 59 19 14 24 21 74 -18 27 46 37 32 56 48 27 7 48 33 38 50 125 0 0 30 49 46 19 14 25 22 75 -17 28 17 9 33 27 52 27 38 16 34 9 59 126 0 0 31 20 35 19 14 27 23 76 -16 28 47 43 33 58 57 28 8 47 34 41 9 127 0 0 31 51 26 19 14 28 24 76 -15 29 18 21 34 30 3 28 39 21 35 12 19 128 0 0 32 22 17 19 14 30 24 77 -14 29 48 59 35 1 8 29 9 56 35 43 29 129 0 0 32 53 8 19 14 31 25 78 -13 30 19 38 35 32 12 29 40 32 36 14 36 130 0 0 33 23 57 19 14 33 26 78 -12 30 50 17 36 3 14 30 11 8 36 45 41 131 0 0 33 54 44 19 14 35 27 79 -11 31 20 54 36 34 12 30 41 43 37 16 42 132 0 0 34 25 28 19 14 36 28 80 -10 31 51 29 37 5 5 31 12 15 37 47 38 133 0 0 34 56 7 19 14 38 29 81 -9 32 22 0 37 35 53 31 42 45 38 18 28 134 0 0 35 26 41 19 14 40 30 81 -8 32 52 27 38 6 34 32 13 10 38 49 12 135 0 0 35 57 8 19 14 42 31 82 -7 33 22 49 38 37 8 32 43 30 39 19 47 136 0 0 36 27 28 19 14 44 32 83 -6 33 53 4 39 7 33 33 13 45 39 50 13 137 0 0 36 57 40 19 14 46 33 84 -6 34 23 12 39 37 48 33 43 52 40 20 30 138 0 0 37 27 42 19 14 48 33 85 -5 34 53 12 40 7 54 34 13 52 40 50 36 139 0 0 37 57 35 19 14 50 34 86 -4 35 23 4 40 37 48 34 43 42 41 20 30 140 0 0 38 27 17 19 14 52 35 87 -3 35 52 45 41 7 29 35 13 24 41 50 12 141 0 0 38 56 46 19 14 54 36 87 -2 36 22 16 41 36 58 35 42 55 42 19 41 142 0 0 39 26 4 19 14 56 37 88 -1 36 51 35 42 6 13 36 12 15 42 48 55 Uncertainty in time = +/- 2 secs [Prediction of 2008 Jun 6.0] Data for the target star ------------------------ * name: TYC 1813-01183-1 * constellation : Taurus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 04 01 29.3632 DE: +23 17 06.612 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .020, .017 ) * V mag [mag]: 11.3 * B mag [mag]: 11.8 * Apparent position with proper motion RA(deg): 60.4982133838 DE(deg): 23.3098767065 * Equation of equinoxes (radians) : 0.000050936626538 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (10) Hygiea approx. diameter [km]: 407 approx. diameter ["]: .136 distance from Earth [AU]: 4.13600 * orbital information: orbit source: Preston date of fit: 2008 Jun 04 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 2203 number of rejected observations: 259 time covered by the observations: 1901 Oct 12 - 2008 Feb 29 1 sigma uncertainty ellipse (major, minor, PA): 0.007, 0.006, 82° remarks: * orbital elements for (10) Hygiea : Mean anomaly = 172.77179898 deg Arg. of pericenter = 313.18313316 deg Long. of node = 283.44986476 deg Inclination = 3.84223549 deg Eccentricity = 0.11751593 Semimajor axis = 3.13813518 AU Perihelion dist = 2.76935432 AU Mag: H = 5.37, G = 0.15 Epoch of elements : MJD 54657.80300000 TDT (2008 Jul 10.803) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Jul 10 10 Hygiea 19h 16.7m UT 11.3 4 1 29.363 23 17 6.61TYC 1813-01183-1 11.8 12.0 407 11.7 4.136 2.980 8.49 -157.8809 23.283 -107.80 22.11 19.2780 -0.11214 0.54661 19.31267 3.99279 -0.00405 -0.00063 2000 171.3883662008 7 3.00000313.183133283.449865 3.8422350.11751593 3.1381352 2.7693543 5.4 5.00.15 RATE 1.7729500 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.021 0.018 89 1.13 0.018 0 54623.5020080710_1183-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Jun 06, 22:38 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org