IOTA/IOTA-ES occultation update for (551) Ortrud / TYC 1403-01395-1 event on 2012 Oct 06, 10:57 UT Visible from S Canada, NW USA Summary ------- On 2012 Oct 06 UT, the 77 km diameter asteroid (551) Ortrud will occult a 9.8 mag star in the constellation Leo for observers along a path across S Canada, NW USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 5.3 mag to 15.1 mag (the magnitude of the asteroid) for at most 2.2 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Hugh Harris, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 62 * date and approx. time of event: 2012 Oct 06, 10:54 - 2012 Oct 06, 10:55 UT * geocentric midpoint of event [JD]: 2456206.95657917 * magnitude of target star: 9.8 * magnitude drop [mag]: 5.3 * estimated maximum duration [s]: 2.2 * Moon: 68 % sunlit, 57° distance * Sun: 54° distance * rough path description: S Canada, NW USA The occultation path -------------------- * approximate projected width [km]: 86 * 1 sigma uncertainty interval [path widths]: +/- 0.99 * 1 sigma uncertainty interval [seconds]: +/- 1.8 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .027 +/- .034) * 1 sigma uncertainty ellipse (major, minor, PA): ( .034", .027", 1° ) * approx speed of asteroid's shadow [km/s]: 34.5874 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1403-01395-1 by 551 Ortrud on 2012 Oct 6 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 -142 0 0 43 21 21 10 54 45 0 69 -46 .. .. .. 43 46 30 .. .. .. 44 36 37 -141 0 0 43 38 9 10 54 45 1 70 -46 43 13 8 44 3 15 .. .. .. 44 53 17 -140 0 0 43 54 37 10 54 45 2 70 -45 43 29 40 44 19 41 .. .. .. 45 9 36 -139 0 0 44 10 46 10 54 45 2 71 -44 43 45 52 44 35 47 42 56 49 45 25 36 -138 0 0 44 26 35 10 54 46 3 72 -44 44 1 44 44 51 33 43 12 47 45 41 15 -137 0 0 44 42 4 10 54 46 4 72 -43 44 17 16 45 6 59 43 28 25 45 56 35 -136 0 0 44 57 13 10 54 46 5 73 -42 44 32 28 45 22 5 43 43 43 46 11 35 -135 0 0 45 12 3 10 54 46 5 74 -42 44 47 20 45 36 51 43 58 41 46 26 15 -134 0 0 45 26 32 10 54 46 6 74 -41 45 1 52 45 51 17 44 13 19 46 40 36 -133 0 0 45 40 41 10 54 47 7 75 -40 45 16 5 46 5 24 44 27 37 46 54 36 -132 0 0 45 54 31 10 54 47 8 76 -40 45 29 57 46 19 10 44 41 35 47 8 16 -131 0 0 46 8 0 10 54 47 8 77 -39 45 43 29 46 32 36 44 55 13 47 21 37 -130 0 0 46 21 10 10 54 48 9 77 -38 45 56 42 46 45 43 45 8 31 47 34 37 -129 0 0 46 33 59 10 54 48 10 78 -38 46 9 34 46 58 30 45 21 29 47 47 18 -128 0 0 46 46 29 10 54 49 10 79 -37 46 22 7 47 10 57 45 34 8 47 59 39 -127 0 0 46 58 39 10 54 49 11 80 -36 46 34 20 47 23 4 45 46 26 48 11 41 -126 0 0 47 10 30 10 54 50 12 80 -36 46 46 13 47 34 52 45 58 24 48 23 23 -125 0 0 47 22 0 10 54 50 13 81 -35 46 57 46 47 46 19 46 10 3 48 34 45 -124 0 0 47 33 11 10 54 51 13 82 -34 47 9 0 47 57 27 46 21 22 48 45 48 -123 0 0 47 44 2 10 54 51 14 83 -34 47 19 54 48 8 16 46 32 21 48 56 31 -122 0 0 47 54 34 10 54 52 15 83 -33 47 30 28 48 18 45 46 43 1 49 6 55 -121 0 0 48 4 46 10 54 53 15 84 -32 47 40 43 48 28 55 46 53 20 49 16 59 -120 0 0 48 14 39 10 54 53 16 85 -32 47 50 38 48 38 45 47 3 20 49 26 44 -119 0 0 48 24 12 10 54 54 17 86 -31 48 0 14 48 48 16 47 13 1 49 36 10 -118 0 0 48 33 26 10 54 55 17 86 -30 48 9 30 48 57 27 47 22 22 49 45 17 -117 0 0 48 42 21 10 54 56 18 87 -30 48 18 27 49 6 20 47 31 24 49 54 4 -116 0 0 48 50 57 10 54 56 19 88 -29 48 27 5 49 14 53 47 40 6 50 2 33 -115 0 0 48 59 13 10 54 57 19 89 -28 48 35 24 49 23 7 47 48 29 50 10 43 -114 0 0 49 7 10 10 54 58 20 90 -28 48 43 23 49 31 2 47 56 33 50 18 33 -113 0 0 49 14 49 10 54 59 21 90 -27 48 51 4 49 38 39 48 4 17 50 26 5 -112 0 0 49 22 8 10 55 0 21 91 -26 48 58 25 49 45 56 48 11 42 50 33 19 -111 0 0 49 29 9 10 55 1 22 92 -26 49 5 28 49 52 55 48 18 49 50 40 13 -110 0 0 49 35 50 10 55 2 23 93 -25 49 12 11 49 59 34 48 25 36 50 46 49 -109 0 0 49 42 13 10 55 2 23 94 -25 49 18 36 50 5 55 48 32 4 50 53 7 -108 0 0 49 48 17 10 55 3 24 95 -24 49 24 42 50 11 58 48 38 13 50 59 6 -107 0 0 49 54 3 10 55 4 25 95 -23 49 30 29 50 17 42 48 44 3 51 4 46 -106 0 0 49 59 30 10 55 5 25 96 -23 49 35 57 50 23 7 48 49 35 51 10 8 -105 0 0 50 4 38 10 55 6 26 97 -22 49 41 7 50 28 14 48 54 48 51 15 12 -104 0 0 50 9 28 10 55 7 27 98 -21 49 45 59 50 33 2 48 59 42 51 19 58 -103 0 0 50 13 59 10 55 9 27 99 -21 49 50 31 50 37 32 49 4 17 51 24 25 -102 0 0 50 18 12 10 55 10 28 100 -20 49 54 45 50 41 44 49 8 34 51 28 34 -101 0 0 50 22 7 10 55 11 28 100 -19 49 58 41 50 45 38 49 12 32 51 32 26 -100 0 0 50 25 43 10 55 12 29 101 -19 50 2 19 50 49 13 49 16 11 51 35 59 - 99 0 0 50 29 1 10 55 13 30 102 -18 50 5 38 50 52 30 49 19 32 51 39 14 - 98 0 0 50 32 1 10 55 14 30 103 -18 50 8 38 50 55 29 49 22 35 51 42 11 - 97 0 0 50 34 43 10 55 15 31 104 -17 50 11 21 50 58 9 49 25 19 51 44 50 - 96 0 0 50 37 6 10 55 16 31 105 -16 50 13 45 51 0 32 49 27 44 51 47 11 - 95 0 0 50 39 11 10 55 18 32 106 -16 50 15 51 51 2 37 49 29 51 51 49 14 - 94 0 0 50 40 58 10 55 19 33 107 -15 50 17 38 51 4 23 49 31 40 51 50 59 - 93 0 0 50 42 27 10 55 20 33 108 -14 50 19 8 51 5 51 49 33 10 51 52 27 - 92 0 0 50 43 38 10 55 21 34 108 -14 50 20 19 51 7 2 49 34 22 51 53 36 - 91 0 0 50 44 31 10 55 23 34 109 -13 50 21 12 51 7 54 49 35 16 51 54 28 - 90 0 0 50 45 5 10 55 24 35 110 -12 50 21 46 51 8 29 49 35 51 51 55 2 - 89 0 0 50 45 22 10 55 25 36 111 -12 50 22 3 51 8 45 49 36 8 51 55 18 - 88 0 0 50 45 20 10 55 27 36 112 -11 50 22 1 51 8 43 49 36 6 51 55 16 - 87 0 0 50 45 0 10 55 28 37 113 -11 50 21 41 51 8 23 49 35 46 51 54 57 - 86 0 0 50 44 22 10 55 30 37 114 -10 50 21 3 51 7 46 49 35 8 51 54 19 - 85 0 0 50 43 26 10 55 31 38 115 -9 50 20 7 51 6 50 49 34 11 51 53 24 - 84 0 0 50 42 12 10 55 32 39 116 -9 50 18 53 51 5 36 49 32 56 51 52 11 - 83 0 0 50 40 40 10 55 34 39 117 -8 50 17 20 51 4 4 49 31 22 51 50 40 - 82 0 0 50 38 49 10 55 35 40 118 -7 50 15 29 51 2 14 49 29 30 51 48 51 - 81 0 0 50 36 40 10 55 37 40 119 -7 50 13 19 51 0 6 49 27 19 51 46 44 - 80 0 0 50 34 13 10 55 38 41 120 -6 50 10 52 50 57 40 49 24 50 51 44 19 - 79 0 0 50 31 28 10 55 40 41 121 -5 50 8 6 50 54 55 49 22 3 51 41 36 - 78 0 0 50 28 24 10 55 41 42 122 -5 50 5 1 50 51 52 49 18 57 51 38 35 - 77 0 0 50 25 2 10 55 43 43 123 -4 50 1 38 50 48 31 49 15 32 51 35 16 - 76 0 0 50 21 22 10 55 45 43 124 -4 49 57 57 50 44 52 49 11 49 51 31 39 - 75 0 0 50 17 23 10 55 46 44 125 -3 49 53 57 50 40 55 49 7 46 51 27 44 - 74 0 0 50 13 6 10 55 48 44 126 -2 49 49 39 50 36 38 49 3 26 51 23 30 - 73 0 0 50 8 30 10 55 49 45 128 -2 49 45 1 50 32 4 48 58 46 51 18 58 - 72 0 0 50 3 36 10 55 51 45 129 -1 49 40 6 50 27 11 48 53 47 51 14 8 - 71 0 0 49 58 23 10 55 53 46 130 0 49 34 51 50 21 59 48 48 30 51 8 59 Uncertainty in time = +/- 2 secs Prediction of 2012 Aug 26.0 Data for the target star ------------------------ * name: TYC 1403-01395-1 * constellation : Leo * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 09 27 12.6757 DE: +15 19 46.654 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .022, .033 ) * V mag [mag]: 9.8 * B mag [mag]: 10.1 * Apparent position with proper motion RA(deg): 141.9787021954 DE(deg): 15.2727440730 * Equation of equinoxes (radians) : 0.000062261490945 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (551) Ortrud approx. diameter [km]: 77 approx. diameter ["]: .034 distance from Earth [AU]: 3.15600 * orbital information: orbit source: Preston date of fit: 2012 Jul 09 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1607 number of rejected observations: 128 time covered by the observations: 1904 Nov 17 - 2012 Mar 25 1 sigma uncertainty ellipse (major, minor, PA): 0.016, 0.009, 108° remarks: * orbital elements for (551) Ortrud : Mean anomaly = 37.96687601 deg Arg. of pericenter = 67.88428253 deg Long. of node = 6.02523785 deg Inclination = 0.39772822 deg Eccentricity = 0.12419360 Semimajor axis = 2.96525035 AU Perihelion dist = 2.59698523 AU Mag: H = 9.55, G = 0.15 Epoch of elements : MJD 56206.45700000 TDT (2012 Oct 06.457) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Oct 6 551 Ortrud 10h 57.5m UT 9.8 9 27 12.676 15 19 46.65TYC 1403-01395-1 10.1 15.1 77 2.2 3.156 3.573 -16.94 -38.0756 15.335 12.63 -5.37 10.9579 0.13706 0.43219 18.55157 -6.07882 -0.00437 0.00146 2000 36.7205182012 930.00000 67.884283 6.025238 0.3977280.12419360 2.9652504 2.5969852 9.6 5.00.15 RATE 1.9302430 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.034 0.027 1 1.99 0.034 0 0-3 4 056165.0020121006_1395-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Aug 26, 01:03 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org