IOTA/IOTA-ES occultation update for (654) Zelinda / TYC 6724-00277-1 event on 2012 Dec 20, 06:03 UT Visible from E Brazil Summary ------- On 2012 Dec 20 UT, the 124 km diameter asteroid (654) Zelinda will occult a 9.2 mag star in the constellation Hydra for observers along a path across E Brazil. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.8 mag to 13.0 mag (the magnitude of the asteroid) for at most 3.3 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: 97 * date and approx. time of event: 2012 Dec 20, 06:01 - 2012 Dec 20, 06:02 UT * geocentric midpoint of event [JD]: 2456281.75268333 * magnitude of target star: 9.2 * magnitude drop [mag]: 3.8 * estimated maximum duration [s]: 3.3 * Moon: 50 % sunlit, 141° distance * Sun: 53° distance * rough path description: E Brazil The occultation path -------------------- * approximate projected width [km]: 163 * 1 sigma uncertainty interval [path widths]: +/- 0.38 * 1 sigma uncertainty interval [seconds]: +/- 1.2 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .028 +/- .027) * 1 sigma uncertainty ellipse (major, minor, PA): ( .028", .027", 91° ) * approx speed of asteroid's shadow [km/s]: 37.6274 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6724-00277-1 by 654 Zelinda on 2012 Dec 20 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 - 67 0 0 -12 25 27 6 1 43 0 118 -47 -13 16 23 .. .. .. -13 55 36 .. .. .. - 66 0 0 -12 57 57 6 1 43 1 118 -46 -13 49 16 -12 7 24 -14 28 47 .. .. .. - 65 0 0 -13 31 24 6 1 43 2 118 -45 -14 23 5 -12 40 28 -15 2 55 .. .. .. - 64 0 0 -14 5 46 6 1 43 3 118 -44 -14 57 51 -13 14 26 -15 38 0 -12 35 56 - 63 0 0 -14 41 3 6 1 44 5 117 -43 -15 33 33 -13 49 20 -16 14 1 -13 10 32 - 62 0 0 -15 17 16 6 1 44 6 117 -42 -16 10 12 -14 25 9 -16 51 0 -13 46 3 - 61 0 0 -15 54 24 6 1 45 7 117 -41 -16 47 46 -15 1 52 -17 28 55 -14 22 28 - 60 0 0 -16 32 27 6 1 45 8 117 -40 -17 26 16 -15 39 29 -18 7 46 -14 59 46 - 59 0 0 -17 11 25 6 1 46 9 116 -39 -18 5 42 -16 18 0 -18 47 34 -15 37 58 - 58 0 0 -17 51 17 6 1 47 10 116 -38 -18 46 2 -16 57 26 -19 28 17 -16 17 4 - 57 0 0 -18 32 3 6 1 47 11 116 -37 -19 27 18 -17 37 44 -20 9 56 -16 57 2 - 56 0 0 -19 13 43 6 1 48 13 115 -35 -20 9 27 -18 18 55 -20 52 30 -17 37 52 - 55 0 0 -19 56 15 6 1 49 14 115 -34 -20 52 31 -19 0 59 -21 35 57 -18 19 35 - 54 0 0 -20 39 40 6 1 51 15 114 -33 -21 36 27 -19 43 54 -22 20 18 -19 2 8 - 53 0 0 -21 23 56 6 1 52 16 114 -32 -22 21 15 -20 27 39 -23 5 32 -19 45 32 - 52 0 0 -22 9 3 6 1 53 17 114 -31 -23 6 55 -21 12 15 -23 51 38 -20 29 45 - 51 0 0 -22 54 59 6 1 55 18 113 -30 -23 53 24 -21 57 40 -24 38 35 -21 14 46 - 50 0 0 -23 41 44 6 1 56 19 113 -28 -24 40 43 -22 43 52 -25 26 21 -22 0 36 - 49 0 0 -24 29 17 6 1 58 21 112 -27 -25 28 50 -23 30 52 -26 14 56 -22 47 11 - 48 0 0 -25 17 35 6 1 59 22 111 -26 -26 17 44 -24 18 37 -27 4 18 -23 34 32 - 47 0 0 -26 6 38 6 2 1 23 111 -25 -27 7 23 -25 7 6 -27 54 25 -24 22 37 - 46 0 0 -26 56 24 6 2 3 24 110 -24 -27 57 45 -25 56 18 -28 45 17 -25 11 24 - 45 0 0 -27 46 51 6 2 5 25 110 -22 -28 48 49 -26 46 10 -29 36 51 -26 0 52 - 44 0 0 -28 37 58 6 2 7 26 109 -21 -29 40 33 -27 36 42 -30 29 5 -26 50 58 - 43 0 0 -29 29 42 6 2 9 27 108 -20 -30 32 55 -28 27 51 -31 21 57 -27 41 42 - 42 0 0 -30 22 2 6 2 12 29 107 -19 -31 25 53 -29 19 35 -32 15 25 -28 33 0 - 41 0 0 -31 14 54 6 2 14 30 106 -17 -32 19 23 -30 11 52 -33 9 27 -29 24 52 - 40 0 0 -32 8 18 6 2 16 31 106 -16 -33 13 25 -31 4 40 -34 3 59 -30 17 13 - 39 0 0 -33 2 9 6 2 19 32 105 -15 -34 7 55 -31 57 56 -34 59 0 -31 10 4 - 38 0 0 -33 56 26 6 2 22 33 104 -14 -35 2 50 -32 51 37 -35 54 27 -32 3 19 - 37 0 0 -34 51 6 6 2 24 34 103 -12 -35 58 8 -33 45 41 -36 50 16 -32 56 58 - 36 0 0 -35 46 5 6 2 27 35 101 -11 -36 53 45 -34 40 5 -37 46 24 -33 50 57 - 35 0 0 -36 41 21 6 2 30 36 100 -10 -37 49 39 -35 34 46 -38 42 48 -34 45 12 - 34 0 0 -37 36 50 6 2 32 37 99 -9 -38 45 45 -36 29 40 -39 39 24 -35 39 42 - 33 0 0 -38 32 29 6 2 35 38 98 -8 -39 42 0 -37 24 45 -40 36 10 -36 34 23 - 32 0 0 -39 28 14 6 2 38 39 97 -6 -40 38 22 -38 19 57 -41 33 0 -37 29 12 - 31 0 0 -40 24 2 6 2 41 39 95 -5 -41 34 45 -39 15 13 -42 29 52 -38 24 4 - 30 0 0 -41 19 50 6 2 44 40 94 -4 -42 31 6 -40 10 29 -43 26 41 -39 18 58 - 29 0 0 -42 15 33 6 2 47 41 93 -3 -43 27 22 -41 5 42 -44 23 24 -40 13 49 - 28 0 0 -43 11 7 6 2 50 42 91 -2 -44 23 28 -42 0 48 -45 19 56 -41 8 35 - 27 0 0 -44 6 30 6 2 53 43 90 -1 -45 19 21 -42 55 43 -46 16 14 -42 3 10 Uncertainty in time = +/- 1 secs Prediction of 2012 Dec 17.0 Data for the target star ------------------------ * name: TYC 6724-00277-1 * constellation : Hydra * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 13 56 05.5137 DE: -27 40 44.304 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .027, .027 ) * V mag [mag]: 9.2 * B mag [mag]: 9.6 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (654) Zelinda approx. diameter [km]: 124 approx. diameter ["]: .072 distance from Earth [AU]: 2.36800 * orbital information: orbit source: Preston date of fit: 2012 Jul 10 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1267 number of rejected observations: 70 time covered by the observations: 1908 Jan 04 - 2012 Feb 19 1 sigma uncertainty ellipse (major, minor, PA): 0.010, 0.005, 102° remarks: * orbital elements for (654) Zelinda : Mean anomaly = 38.71667008 deg Arg. of pericenter = 213.88338471 deg Long. of node = 278.48538533 deg Inclination = 18.12720026 deg Eccentricity = 0.23104246 Semimajor axis = 2.29696975 AU Perihelion dist = 1.76627221 AU Mag: H = 8.55, G = 0.15 Epoch of elements : MJD 56281.25300000 TDT (2012 Dec 20.253) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Dec 20 654 Zelinda 6h 3.9m UT 9.2 13 56 5.514-27 40 44.30TYC 6724-00277-1 9.6 13.0 124 3.3 2.368 5.313 -35.23 28.8253 -27.670 88.46 -23.43 6.0644 -0.28998 -0.58074 19.00118 -9.48717 -0.00430 0.00074 2000 38.36192020121219.00000213.883385278.485385 18.1272000.23104246 2.2969698 1.7662722 8.5 5.00.15 RATE 2.8312040 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.028 0.027 91 1.38 0.028 0 0-3-4 056278.0020121220_0277-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Jul 10, 06:06 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org