IOTA/IOTA-ES occultation update for (424) Gratia / TYC 0858-01136-1 event on 2012 Nov 19, 23:27 UT Visible from SW Asia Summary ------- On 2012 Nov 19 UT, the 89 km diameter asteroid (424) Gratia will occult a 11.0 mag star in the constellation Leo for observers along a path across SW Asia. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.9 mag to 14.9 mag (the magnitude of the asteroid) for at most 3.4 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: 84 * date and approx. time of event: 2012 Nov 19, 23:23 - 2012 Nov 19, 23:26 UT * geocentric midpoint of event [JD]: 2456251.47739167 * magnitude of target star: 11.0 * magnitude drop [mag]: 3.9 * estimated maximum duration [s]: 3.4 * Moon: 43 % sunlit, 151° distance * Sun: 72° distance * rough path description: SW Asia The occultation path -------------------- * approximate projected width [km]: 94 * 1 sigma uncertainty interval [path widths]: +/- 0.61 * 1 sigma uncertainty interval [seconds]: +/- 2.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .032 +/- .027) * 1 sigma uncertainty ellipse (major, minor, PA): ( .032", .027", 97° ) * approx speed of asteroid's shadow [km/s]: 25.9002 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 0858-01136-1 by 424 Gratia on 2012 Nov 19 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 23 0 0 32 28 4 23 23 34 1 78 -70 32 2 1 32 54 11 31 30 19 33 26 8 24 0 0 32 39 13 23 23 34 2 78 -69 32 13 11 33 5 18 31 41 31 33 37 14 25 0 0 32 50 7 23 23 34 2 79 -68 32 24 7 33 16 11 31 52 29 33 48 4 26 0 0 33 0 46 23 23 34 3 79 -67 32 34 47 33 26 48 32 3 11 33 58 40 27 0 0 33 11 10 23 23 35 4 80 -67 32 45 13 33 37 11 32 13 38 34 9 1 28 0 0 33 21 18 23 23 35 5 80 -66 32 55 23 33 47 18 32 23 50 34 19 6 29 0 0 33 31 12 23 23 35 6 81 -65 33 5 18 33 57 10 32 33 47 34 28 56 30 0 0 33 40 50 23 23 36 7 82 -64 33 14 57 34 6 47 32 43 28 34 38 31 31 0 0 33 50 13 23 23 36 7 82 -63 33 24 22 34 16 8 32 52 54 34 47 51 32 0 0 33 59 20 23 23 37 8 83 -62 33 33 30 34 25 14 33 2 5 34 56 55 33 0 0 34 8 12 23 23 37 9 83 -62 33 42 23 34 34 4 33 10 59 35 5 44 34 0 0 34 16 48 23 23 38 10 84 -61 33 51 1 34 42 39 33 19 38 35 14 16 35 0 0 34 25 8 23 23 39 11 84 -60 33 59 22 34 50 58 33 28 1 35 22 34 36 0 0 34 33 12 23 23 39 12 85 -59 34 7 28 34 59 1 33 36 9 35 30 35 37 0 0 34 41 1 23 23 40 13 86 -58 34 15 18 35 6 48 33 44 0 35 38 21 38 0 0 34 48 34 23 23 41 13 86 -58 34 22 52 35 14 20 33 51 36 35 45 51 39 0 0 34 55 51 23 23 42 14 87 -57 34 30 10 35 21 35 33 58 55 35 53 5 40 0 0 35 2 52 23 23 43 15 87 -56 34 37 12 35 28 35 34 5 59 36 0 4 41 0 0 35 9 37 23 23 44 16 88 -55 34 43 58 35 35 19 34 12 46 36 6 46 42 0 0 35 16 6 23 23 45 17 89 -54 34 50 28 35 41 47 34 19 18 36 13 12 43 0 0 35 22 18 23 23 46 17 89 -53 34 56 42 35 47 58 34 25 33 36 19 23 44 0 0 35 28 15 23 23 47 18 90 -53 35 2 40 35 53 54 34 31 32 36 25 17 45 0 0 35 33 55 23 23 48 19 90 -52 35 8 21 35 59 33 34 37 14 36 30 55 46 0 0 35 39 20 23 23 50 20 91 -51 35 13 46 36 4 57 34 42 41 36 36 17 47 0 0 35 44 28 23 23 51 21 92 -50 35 18 55 36 10 4 34 47 51 36 41 23 48 0 0 35 49 20 23 23 52 22 92 -49 35 23 48 36 14 55 34 52 45 36 46 13 49 0 0 35 53 55 23 23 54 22 93 -49 35 28 24 36 19 30 34 57 22 36 50 47 50 0 0 35 58 14 23 23 55 23 93 -48 35 32 45 36 23 48 35 1 43 36 55 4 51 0 0 36 2 17 23 23 57 24 94 -47 35 36 48 36 27 50 35 5 48 36 59 6 52 0 0 36 6 4 23 23 58 25 95 -46 35 40 35 36 31 36 35 9 36 37 2 51 53 0 0 36 9 34 23 24 0 26 95 -45 35 44 6 36 35 6 35 13 7 37 6 19 54 0 0 36 12 48 23 24 1 26 96 -45 35 47 21 36 38 19 35 16 23 37 9 32 55 0 0 36 15 45 23 24 3 27 97 -44 35 50 19 36 41 16 35 19 21 37 12 28 56 0 0 36 18 26 23 24 5 28 97 -43 35 53 0 36 43 56 35 22 3 37 15 8 57 0 0 36 20 51 23 24 6 29 98 -42 35 55 25 36 46 20 35 24 29 37 17 31 58 0 0 36 22 59 23 24 8 30 99 -41 35 57 34 36 48 28 35 26 38 37 19 38 59 0 0 36 24 51 23 24 10 30 99 -40 35 59 26 36 50 19 35 28 30 37 21 29 60 0 0 36 26 26 23 24 12 31 100 -40 36 1 1 36 51 54 35 30 6 37 23 4 61 0 0 36 27 44 23 24 14 32 101 -39 36 2 20 36 53 12 35 31 26 37 24 22 62 0 0 36 28 46 23 24 16 33 102 -38 36 3 22 36 54 14 35 32 28 37 25 23 63 0 0 36 29 32 23 24 18 34 102 -37 36 4 8 36 55 0 35 33 14 37 26 9 64 0 0 36 30 1 23 24 20 34 103 -36 36 4 38 36 55 29 35 33 44 37 26 37 65 0 0 36 30 14 23 24 22 35 104 -36 36 4 50 36 55 41 35 33 56 37 26 50 66 0 0 36 30 10 23 24 24 36 104 -35 36 4 46 36 55 37 35 33 52 37 26 46 67 0 0 36 29 49 23 24 26 37 105 -34 36 4 26 36 55 17 35 33 32 37 26 25 68 0 0 36 29 12 23 24 29 38 106 -33 36 3 48 36 54 40 35 32 54 37 25 48 69 0 0 36 28 19 23 24 31 38 107 -32 36 2 55 36 53 46 35 32 1 37 24 55 70 0 0 36 27 8 23 24 33 39 107 -32 36 1 44 36 52 36 35 30 50 37 23 45 71 0 0 36 25 42 23 24 36 40 108 -31 36 0 17 36 51 10 35 29 23 37 22 19 72 0 0 36 23 58 23 24 38 41 109 -30 35 58 34 36 49 26 35 27 39 37 20 36 73 0 0 36 21 58 23 24 40 41 110 -29 35 56 33 36 47 27 35 25 38 37 18 37 74 0 0 36 19 42 23 24 43 42 111 -28 35 54 16 36 45 11 35 23 20 37 16 21 75 0 0 36 17 8 23 24 45 43 112 -27 35 51 43 36 42 38 35 20 46 37 13 49 76 0 0 36 14 19 23 24 48 44 112 -27 35 48 52 36 39 49 35 17 55 37 11 0 77 0 0 36 11 12 23 24 50 45 113 -26 35 45 46 36 36 43 35 14 48 37 7 55 78 0 0 36 7 49 23 24 53 45 114 -25 35 42 22 36 33 20 35 11 24 37 4 34 79 0 0 36 4 10 23 24 56 46 115 -24 35 38 42 36 29 41 35 7 43 37 0 55 80 0 0 36 0 14 23 24 58 47 116 -23 35 34 45 36 25 46 35 3 45 36 57 1 81 0 0 35 56 1 23 25 1 48 117 -23 35 30 32 36 21 34 34 59 31 36 52 50 82 0 0 35 51 32 23 25 4 48 118 -22 35 26 1 36 17 5 34 55 0 36 48 22 83 0 0 35 46 46 23 25 7 49 119 -21 35 21 15 36 12 20 34 50 12 36 43 38 84 0 0 35 41 43 23 25 10 50 120 -20 35 16 11 36 7 19 34 45 8 36 38 38 85 0 0 35 36 24 23 25 13 51 121 -19 35 10 51 36 2 1 34 39 46 36 33 21 86 0 0 35 30 49 23 25 15 51 122 -18 35 5 15 35 56 26 34 34 9 36 27 47 87 0 0 35 24 56 23 25 18 52 123 -18 34 59 22 35 50 35 34 28 14 36 21 57 88 0 0 35 18 48 23 25 21 53 124 -17 34 53 12 35 44 27 34 22 4 36 15 51 89 0 0 35 12 23 23 25 24 54 125 -16 34 46 46 35 38 3 34 15 36 36 9 28 90 0 0 35 5 41 23 25 28 54 126 -15 34 40 3 35 31 23 34 8 52 36 2 49 91 0 0 34 58 43 23 25 31 55 127 -14 34 33 4 35 24 26 34 1 51 35 55 54 92 0 0 34 51 29 23 25 34 56 128 -13 34 25 48 35 17 13 33 54 34 35 48 42 93 0 0 34 43 58 23 25 37 57 130 -13 34 18 16 35 9 43 33 47 1 35 41 14 94 0 0 34 36 10 23 25 40 57 131 -12 34 10 28 35 1 57 33 39 11 35 33 29 95 0 0 34 28 7 23 25 43 58 132 -11 34 2 23 34 53 55 33 31 4 35 25 29 96 0 0 34 19 47 23 25 47 59 133 -10 33 54 2 34 45 36 33 22 41 35 17 12 97 0 0 34 11 11 23 25 50 59 135 -9 33 45 24 34 37 1 33 14 2 35 8 39 98 0 0 34 2 18 23 25 53 60 136 -8 33 36 30 34 28 11 33 5 7 34 59 49 99 0 0 33 53 10 23 25 57 61 138 -8 33 27 20 34 19 3 32 55 55 34 50 44 100 0 0 33 43 45 23 26 0 61 139 -7 33 17 54 34 9 40 32 46 27 34 41 23 101 0 0 33 34 5 23 26 4 62 141 -6 33 8 12 34 0 1 32 36 43 34 31 45 102 0 0 33 24 8 23 26 7 63 142 -5 32 58 14 33 50 6 32 26 43 34 21 52 103 0 0 33 13 55 23 26 11 63 144 -4 32 48 0 33 39 55 32 16 28 34 11 43 104 0 0 33 3 27 23 26 14 64 146 -3 32 37 30 33 29 28 32 5 56 34 1 18 105 0 0 32 52 43 23 26 18 65 148 -2 32 26 44 33 18 45 31 55 8 33 50 37 106 0 0 32 41 43 23 26 21 65 150 -2 32 15 43 33 7 47 31 44 5 33 39 41 107 0 0 32 30 27 23 26 25 66 152 -1 32 4 26 32 56 33 31 32 46 33 28 29 Uncertainty in time = +/- 3 secs Prediction of 2012 Nov 16.0 Data for the target star ------------------------ * name: TYC 0858-01136-1 * constellation : Leo * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 11 16 44.7753 DE: +10 45 51.468 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .026, .025 ) * V mag [mag]: 11.0 * B mag [mag]: 11.5 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (424) Gratia approx. diameter [km]: 89 approx. diameter ["]: .044 distance from Earth [AU]: 2.79500 * orbital information: orbit source: Preston date of fit: 2012 Jul 10 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 976 number of rejected observations: 85 time covered by the observations: 1905 Dec 17 - 2012 Apr 01 1 sigma uncertainty ellipse (major, minor, PA): 0.019, 0.010, 109° remarks: * orbital elements for (424) Gratia : Mean anomaly = 62.78657660 deg Arg. of pericenter = 331.56461415 deg Long. of node = 99.25837436 deg Inclination = 8.21009203 deg Eccentricity = 0.10890516 Semimajor axis = 2.77312336 AU Perihelion dist = 2.47111591 AU Mag: H = 9.42, G = 0.15 Epoch of elements : MJD 56250.97700000 TDT (2012 Nov 19.977) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Nov 19 424 Gratia 23h 27.4m UT 11.0 11 16 44.775 10 45 51.47TYC 0858-01136-1 11.5 14.9 89 3.4 2.795 3.027 -11.23 117.9350 10.768 -175.45 -19.72 23.4574 0.07685 0.31029 14.17642 -3.56909 -0.00507 0.00235 2000 62.57805820121119.00000331.564614 99.258374 8.2100920.10890516 2.7731234 2.4711159 9.5 5.00.15 RATE 2.1342750 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.032 0.027 97 1.61 0.027 0 0 3-2 056247.0020121119_1136-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Jul 10, 02:40 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org