IOTA/IOTA-ES occultation update for (1171) Rusthawelia / UCAC2 37837524 event on 2009 Dec 02, 21:33 UT Visible from Summary ------- On 2009 Dec 02 UT, the 67 km diameter asteroid (1171) Rusthawelia will occult a 11.9 mag star in the constellation Taurus for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 1.6 mag to 13.3 mag (the magnitude of the asteroid) for at most 6.8 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: 63 * date and approx. time of event: 2009 Dec 02, 21:27 - 2009 Dec 02, 21:45 UT * magnitude of target star: 11.9 * magnitude drop [mag]: 1.6 * estimated maximum duration [s]: 6.8 * Moon: 99 % sunlit, 15° distance * Sun: 173° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 79 * 1 sigma uncertainty interval [path widths]: +/- 0.97 * 1 sigma uncertainty interval [seconds]: +/- 8.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .071 +/- .057) * 1 sigma uncertainty ellipse (major, minor, PA): ( .072", .056", 85° ) * approx speed of asteroid's shadow [km/s]: 9.8965 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC2 37837524 by 1171 Rusthawelia on 2009 Dec 2 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 - 43 0 0 -32 50 2 21 45 55 8 64 -1 -32 26 57 -33 13 13 -31 42 27 -33 58 31 - 42 0 0 -32 30 24 21 45 53 9 63 -2 -32 7 19 -32 53 35 -31 22 51 -33 38 52 - 41 0 0 -32 10 45 21 45 51 10 63 -3 -31 47 40 -32 33 55 -31 3 13 -33 19 11 - 40 0 0 -31 51 4 21 45 49 10 62 -3 -31 28 1 -32 14 14 -30 43 34 -32 59 29 - 39 0 0 -31 31 23 21 45 47 11 62 -4 -31 8 20 -31 54 33 -30 23 54 -32 39 47 - 38 0 0 -31 11 42 21 45 44 12 61 -5 -30 48 40 -31 34 51 -30 4 15 -32 20 4 - 37 0 0 -30 52 2 21 45 42 13 61 -6 -30 29 0 -31 15 10 -29 44 37 -32 0 21 - 36 0 0 -30 32 22 21 45 39 14 60 -7 -30 9 21 -30 55 29 -29 24 59 -31 40 39 - 35 0 0 -30 12 44 21 45 36 15 60 -8 -29 49 44 -30 35 50 -29 5 23 -31 20 58 - 34 0 0 -29 53 7 21 45 33 16 59 -9 -29 30 8 -30 16 13 -28 45 49 -31 1 19 - 33 0 0 -29 33 33 21 45 29 17 58 -10 -29 10 34 -29 56 37 -28 26 18 -30 41 42 - 32 0 0 -29 14 1 21 45 26 18 58 -11 -28 51 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23 55 102 0 0 -22 34 11 21 27 59 9 293 -11 -22 11 40 -22 56 48 -21 28 16 -23 40 57 103 0 0 -22 51 21 21 27 57 8 293 -10 -22 28 48 -23 13 59 -21 45 20 -23 58 12 104 0 0 -23 8 43 21 27 56 7 292 -9 -22 46 8 -23 31 23 -22 2 37 -24 15 40 105 0 0 -23 26 17 21 27 54 6 292 -9 -23 3 41 -23 48 59 -22 20 6 -24 33 19 106 0 0 -23 44 3 21 27 53 5 291 -8 -23 21 25 -24 6 47 -22 37 47 -24 51 10 107 0 0 -24 2 0 21 27 52 4 291 -7 -23 39 20 -24 24 46 -22 55 39 -25 9 12 108 0 0 -24 20 8 21 27 51 4 291 -6 -23 57 27 -24 42 55 .. .. .. -25 27 26 109 0 0 -24 38 26 21 27 50 3 290 -5 -24 15 44 -25 1 15 .. .. .. -25 45 49 110 0 0 -24 56 55 21 27 50 2 290 -4 -24 34 10 -25 19 46 .. .. .. -26 4 23 111 0 0 -25 15 33 21 27 50 1 289 -3 -24 52 47 -25 38 25 .. .. .. -26 23 6 Uncertainty in time = +/- 8 secs [Prediction of 2008 Mar 20.0] Data for the target star ------------------------ * name: UCAC2 37837524 * constellation : Taurus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 04 14 52.9049 DE: +17 06 42.480 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .052, .052 ) * V mag [mag]: 11.9 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1171) Rusthawelia approx. diameter [km]: 67 approx. diameter ["]: .058 distance from Earth [AU]: 1.60600 * orbital information: orbit source: Preston date of fit: 2008 Mar 20 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 860 number of rejected observations: 87 time covered by the observations: 1904 Mar 15 - 2007 Jul 10 1 sigma uncertainty ellipse (major, minor, PA): 0.049, 0.021, 79° remarks: * orbital elements for (1171) Rusthawelia : Mean anomaly = 11.20994880 deg Arg. of pericenter = 288.08847798 deg Long. of node = 122.24688294 deg Inclination = 3.07575998 deg Eccentricity = 0.19107683 Semimajor axis = 3.17698295 AU Perihelion dist = 2.56993510 AU Mag: H = 9.65, G = 0.15 Epoch of elements : MJD 55167.89800000 TDT (2009 Dec 02.898) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Dec 2 1171 Rusthawelia 21h 36.9m UT 11.9 4 14 52.905 17 6 42.48UCAC2 37837524 0.0 13.3 67 6.8 1.606 -2.123 -2.88 27.6289 17.112 -146.82 -22.07 21.6155 0.04975 -0.52714 -5.56105 -0.52611 0.00050 0.00051 2000 9.83527820091125.00000288.088478122.246883 3.0757600.19107683 3.1769830 2.5699351 9.9 5.00.15 RATE 1.7405310 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.072 0.056 85 1.97 0.056 0 54545.5020091202_837524 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 20, 17:17 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org