IOTA/IOTA-ES occultation update for (666) Desdemona / TYC 5733-00815-1 event on 2008 May 16, 02:54 UT Visible from N Brazil, W Africa Summary ------- On 2008 May 16 UT, the 27 km diameter asteroid (666) Desdemona will occult a 10.3 mag star in the constellation Sagittarius for observers along a path across N Brazil, W Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 5.3 mag to 15.6 mag (the magnitude of the asteroid) for at most 4.4 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: 39 * date and approx. time of event: 2008 May 16, 02:44 - 2008 May 16, 03:05 UT * midpoint of event [JD]: 2454602.62151667 * magnitude of target star: 10.3 * magnitude drop [mag]: 5.3 * estimated maximum duration [s]: 4.4 * Moon: 86 % sunlit, 107° distance * Sun: 117° distance * rough path description: N Brazil, W Africa The occultation path -------------------- * approximate projected width [km]: 46 * 1 sigma uncertainty interval [path widths]: +/- 1.68 * 1 sigma uncertainty interval [seconds]: +/- 7.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .030 +/- .030) * 1 sigma uncertainty ellipse (major, minor, PA): ( .030", .030", 83° ) * approx speed of asteroid's shadow [km/s]: 6.1535 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5733-00815-1 by 666 Desdemona on 2008 May 16 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 ' " Longitude Longitude Longitude Longitude - 39 34 8 67 0 0 3 5 1 1 124 -4 - 38 41 29 - 40 28 40 ... .. .. ... .. .. - 36 23 54 66 0 0 3 4 59 3 127 -5 - 35 38 36 - 37 10 23 ... .. .. - 39 56 57 - 33 48 54 65 0 0 3 4 57 4 130 -5 - 33 8 40 - 34 30 0 - 30 58 58 - 36 55 7 - 31 39 13 64 0 0 3 4 53 5 132 -6 - 31 2 43 - 32 16 21 - 29 4 19 - 34 26 20 - 29 48 47 63 0 0 3 4 49 7 133 -7 - 29 15 12 - 30 22 52 - 27 25 46 - 32 21 26 - 28 13 38 62 0 0 3 4 44 8 135 -8 - 27 42 24 - 28 45 16 - 26 0 16 - 30 34 50 - 26 50 57 61 0 0 3 4 39 9 136 -8 - 26 21 40 - 27 20 34 - 24 45 38 - 29 2 48 - 25 38 40 60 0 0 3 4 33 10 137 -9 - 25 11 2 - 26 6 35 - 23 40 11 - 27 42 43 - 24 35 12 59 0 0 3 4 27 11 138 -10 - 24 8 58 - 25 1 41 - 22 42 37 - 26 32 38 - 23 39 19 58 0 0 3 4 20 12 138 -11 - 23 14 19 - 24 4 33 - 21 51 52 - 25 31 3 - 22 50 4 57 0 0 3 4 12 13 139 -11 - 22 26 8 - 23 14 11 - 21 7 7 - 24 36 48 - 22 6 36 56 0 0 3 4 4 14 139 -12 - 21 43 38 - 22 29 45 - 20 27 41 - 23 48 57 - 21 28 18 55 0 0 3 3 56 15 140 -13 - 21 6 10 - 21 50 35 - 19 52 57 - 23 6 45 - 20 54 36 54 0 0 3 3 47 16 140 -14 - 20 33 14 - 21 16 7 - 19 22 28 - 22 29 34 - 20 25 2 53 0 0 3 3 38 17 140 -14 - 20 4 21 - 20 45 52 - 18 55 49 - 21 56 54 - 19 59 14 52 0 0 3 3 28 18 140 -15 - 19 39 10 - 20 19 26 - 18 32 38 - 21 28 16 - 19 36 51 51 0 0 3 3 18 19 141 -16 - 19 17 21 - 19 56 28 - 18 12 39 - 21 3 20 - 19 17 36 50 0 0 3 3 8 20 141 -17 - 18 58 36 - 19 36 42 - 17 55 35 - 20 41 45 - 19 1 14 49 0 0 3 2 57 21 141 -18 - 18 42 42 - 19 19 51 - 17 41 12 - 20 23 16 - 18 47 31 48 0 0 3 2 46 22 141 -18 - 18 29 26 - 19 5 43 - 17 29 20 - 20 7 38 - 18 36 18 47 0 0 3 2 34 23 140 -19 - 18 18 36 - 18 54 6 - 17 19 47 - 19 54 39 - 18 27 24 46 0 0 3 2 22 23 140 -20 - 18 10 3 - 18 44 50 - 17 12 25 - 19 44 7 - 18 20 40 45 0 0 3 2 10 24 140 -21 - 18 3 39 - 18 37 46 - 17 7 6 - 19 35 54 - 18 15 58 44 0 0 3 1 57 25 140 -22 - 17 59 16 - 18 32 46 - 17 3 43 - 19 29 51 - 18 13 13 43 0 0 3 1 44 26 139 -23 - 17 56 48 - 18 29 44 - 17 2 10 - 19 25 51 - 18 12 19 42 0 0 3 1 30 26 139 -24 - 17 56 8 - 18 28 34 - 17 2 21 - 19 23 48 - 18 13 10 41 0 0 3 1 17 27 139 -25 - 17 57 13 - 18 29 11 - 17 4 12 - 19 23 36 - 18 15 41 40 0 0 3 1 2 28 138 -25 - 17 59 58 - 18 31 30 - 17 7 39 - 19 25 11 - 18 19 50 39 0 0 3 0 48 28 138 -26 - 18 4 18 - 18 35 27 - 17 12 38 - 19 28 28 - 18 25 33 38 0 0 3 0 33 29 137 -27 - 18 10 11 - 18 40 59 - 17 19 7 - 19 33 23 - 18 32 47 37 0 0 3 0 18 30 137 -28 - 18 17 35 - 18 48 3 - 17 27 2 - 19 39 55 - 18 41 29 36 0 0 3 0 2 30 136 -29 - 18 26 26 - 18 56 37 - 17 36 21 - 19 47 59 - 18 51 38 35 0 0 2 59 46 31 135 -30 - 18 36 43 - 19 6 38 - 17 47 3 - 19 57 34 - 19 3 13 34 0 0 2 59 30 32 135 -31 - 18 48 24 - 19 18 6 - 17 59 7 - 20 8 39 - 19 16 11 33 0 0 2 59 13 32 134 -32 - 19 1 28 - 19 30 59 - 18 12 31 - 20 21 12 - 19 30 33 32 0 0 2 58 56 33 133 -33 - 19 15 55 - 19 45 15 - 18 27 14 - 20 35 13 - 19 46 17 31 0 0 2 58 39 33 133 -34 - 19 31 43 - 20 0 56 - 18 43 16 - 20 50 40 - 20 3 25 30 0 0 2 58 21 33 132 -35 - 19 48 54 - 20 18 0 - 19 0 38 - 21 7 33 - 20 21 55 29 0 0 2 58 3 34 131 -36 - 20 7 26 - 20 36 28 - 19 19 18 - 21 25 54 - 20 41 49 28 0 0 2 57 45 34 130 -37 - 20 27 21 - 20 56 20 - 19 39 19 - 21 45 42 - 21 3 7 27 0 0 2 57 26 35 129 -38 - 20 48 40 - 21 17 38 - 20 0 40 - 22 6 58 - 21 25 51 26 0 0 2 57 7 35 128 -39 - 21 11 24 - 21 40 22 - 20 23 23 - 22 29 44 - 21 50 2 25 0 0 2 56 48 35 127 -40 - 21 35 34 - 22 4 35 - 20 47 29 - 22 54 2 - 22 15 43 24 0 0 2 56 28 35 126 -42 - 22 1 12 - 22 30 18 - 21 13 1 - 23 19 54 - 22 42 56 23 0 0 2 56 8 36 125 -43 - 22 28 22 - 22 57 34 - 21 40 1 - 23 47 23 - 23 11 44 22 0 0 2 55 48 36 124 -44 - 22 57 6 - 23 26 27 - 22 8 31 - 24 16 31 - 23 42 10 21 0 0 2 55 28 36 123 -45 - 23 27 26 - 23 56 58 - 22 38 34 - 24 47 23 - 24 14 19 20 0 0 2 55 7 36 122 -46 - 23 59 29 - 24 29 14 - 23 10 16 - 25 20 4 - 24 48 15 19 0 0 2 54 46 36 121 -47 - 24 33 17 - 25 3 19 - 23 43 39 - 25 54 38 - 25 24 4 18 0 0 2 54 24 36 120 -48 - 25 8 56 - 25 39 17 - 24 18 48 - 26 31 11 - 26 1 52 17 0 0 2 54 2 36 119 -50 - 25 46 33 - 26 17 17 - 24 55 50 - 27 9 51 - 26 41 47 16 0 0 2 53 40 36 118 -51 - 26 26 15 - 26 57 24 - 25 34 51 - 27 50 45 - 27 23 56 15 0 0 2 53 18 35 117 -52 - 27 8 10 - 27 39 49 - 26 15 59 - 28 34 4 - 28 8 30 14 0 0 2 52 55 35 116 -53 - 27 52 27 - 28 24 41 - 26 59 23 - 29 19 59 - 28 55 41 13 0 0 2 52 32 35 115 -55 - 28 39 18 - 29 12 12 - 27 45 12 - 30 8 42 - 29 45 42 12 0 0 2 52 8 34 114 -56 - 29 28 56 - 30 2 36 - 28 33 38 - 31 0 30 - 30 38 49 11 0 0 2 51 44 34 113 -57 - 30 21 37 - 30 56 10 - 29 24 57 - 31 55 42 - 31 35 22 10 0 0 2 51 20 33 111 -59 - 31 17 40 - 31 53 15 - 30 19 25 - 32 54 40 - 32 35 46 9 0 0 2 50 55 33 110 -60 - 32 17 28 - 32 54 15 - 31 17 21 - 33 57 54 - 33 40 28 8 0 0 2 50 30 32 109 -61 - 33 21 29 - 33 59 41 - 32 19 11 - 35 5 59 - 34 50 8 7 0 0 2 50 4 31 108 -63 - 34 30 19 - 35 10 13 - 33 25 26 - 36 19 43 - 36 5 33 6 0 0 2 49 38 30 107 -64 - 35 44 43 - 36 26 42 - 34 36 44 - 37 40 7 - 37 27 48 5 0 0 2 49 11 29 107 -65 - 37 5 42 - 37 50 15 - 35 53 56 - 39 8 37 - 38 58 21 4 0 0 2 48 43 27 106 -67 - 38 34 40 - 39 22 28 - 37 18 8 - 40 47 16 - 40 39 21 3 0 0 2 48 15 26 105 -68 - 40 13 35 - 41 5 42 - 38 50 54 - 42 39 15 - 42 34 10 2 0 0 2 47 45 24 104 -69 - 42 5 30 - 43 3 39 - 40 34 29 - 44 50 0 - 44 48 33 1 0 0 2 47 14 22 103 -70 - 44 15 32 - 45 22 53 - 42 32 28 - 47 30 23 Latitude Latitude Latitude Latitude - 46 0 0 0 32 19 2 46 59 21 103 -70 0 18 50 0 45 52 - 0 25 53 1 32 2 - 47 0 0 0 11 12 2 46 47 20 103 -70 - 0 2 8 0 24 37 - 0 46 22 1 10 16 - 48 0 0 - 0 8 0 2 46 35 19 103 -70 - 0 21 12 0 5 17 - 1 5 1 0 50 28 - 49 0 0 - 0 25 21 2 46 24 18 102 -70 - 0 38 26 - 0 12 12 - 1 21 52 0 32 34 - 50 0 0 - 0 40 54 2 46 14 17 102 -70 - 0 53 53 - 0 27 51 - 1 36 58 0 16 32 - 51 0 0 - 0 54 42 2 46 5 16 102 -70 - 1 7 34 - 0 41 45 - 1 50 21 0 2 18 - 52 0 0 - 1 6 46 2 45 56 15 102 -70 - 1 19 33 - 0 53 54 - 2 2 3 - 0 10 10 - 53 0 0 - 1 17 9 2 45 48 14 102 -69 - 1 29 52 - 1 4 22 - 2 12 7 - 0 20 54 - 54 0 0 - 1 25 52 2 45 40 13 102 -69 - 1 38 31 - 1 13 9 - 2 20 34 - 0 29 55 - 55 0 0 - 1 32 58 2 45 33 12 102 -68 - 1 45 34 - 1 20 18 - 2 27 25 - 0 37 16 - 56 0 0 - 1 38 27 2 45 26 11 102 -68 - 1 51 0 - 1 25 50 - 2 32 42 - 0 42 59 - 57 0 0 - 1 42 21 2 45 20 10 102 -67 - 1 54 51 - 1 29 47 - 2 36 26 - 0 47 3 - 58 0 0 - 1 44 40 2 45 15 9 102 -67 - 1 57 9 - 1 32 8 - 2 38 37 - 0 49 31 - 59 0 0 - 1 45 27 2 45 10 8 102 -66 - 1 57 54 - 1 32 56 - 2 39 18 - 0 50 24 - 60 0 0 - 1 44 40 2 45 6 7 102 -65 - 1 57 7 - 1 32 10 - 2 38 28 - 0 49 42 - 61 0 0 - 1 42 22 2 45 2 6 102 -65 - 1 54 48 - 1 29 52 - 2 36 8 - 0 47 25 - 62 0 0 - 1 38 32 2 44 59 5 102 -64 - 1 50 58 - 1 26 2 .. .. .. - 0 43 35 - 63 0 0 - 1 33 10 2 44 56 4 102 -63 - 1 45 37 - 1 20 40 .. .. .. - 0 38 11 - 64 0 0 - 1 26 17 2 44 54 3 102 -62 - 1 38 45 - 1 13 46 .. .. .. - 0 31 13 - 65 0 0 - 1 17 53 2 44 52 2 102 -61 - 1 30 22 - 1 5 20 .. .. .. - 0 22 43 - 66 0 0 - 1 7 57 2 44 51 1 102 -60 - 1 20 28 - 0 55 22 .. .. .. - 0 12 38 - 67 0 0 - 0 56 29 2 44 51 0 102 -60 - 1 9 3 - 0 43 52 .. .. .. - 0 0 59 Uncertainty in time = +/- 7 secs [Prediction of 2008 Feb 17.0] Data for the target star ------------------------ * name: TYC 5733-00815-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 52 20.4060 DE: -11 59 51.762 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .019, .020 ) * V mag [mag]: 10.3 * B mag [mag]: 12.2 * Apparent position with proper motion RA(deg): 298.2063998740 DE(deg): -11.9772945347 * Equation of equinoxes (radians) : 0.000039929313878 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (666) Desdemona approx. diameter [km]: 27 approx. diameter ["]: .018 distance from Earth [AU]: 2.05900 * orbital information: orbit source: Preston date of fit: 2008 Feb 16 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 986 number of rejected observations: 41 time covered by the observations: 1908 Jul 23 - 2007 Aug 14 1 sigma uncertainty ellipse (major, minor, PA): 0.024, 0.022, 79° remarks: * orbital elements for (666) Desdemona : Mean anomaly = 275.70850126 deg Arg. of pericenter = 173.83952576 deg Long. of node = 215.59231854 deg Inclination = 7.58061225 deg Eccentricity = 0.23696354 Semimajor axis = 2.59553404 AU Perihelion dist = 1.98048710 AU Mag: H = 10.60, G = 0.15 Epoch of elements : MJD 54602.12100000 TDT (2008 May 16.121) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 16 666 Desdemona 2h 55.0m UT 10.3 19 52 20.406-11 59 51.76TYC 5733-00815-1 12.2 15.6 27 4.4 2.059 0.579 12.15 20.1393 -12.001 135.35 19.17 2.9164 -0.66281 0.46555 1.99326 2.84431 -0.00474 -0.00132 2000 275.2085762008 514.00000173.839526215.592319 7.5806120.23696354 2.5955340 1.980487110.9 5.00.15 RATE 2.3570240 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.030 0.030 83 2.68 0.030 0 54513.5020080516_0815-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 12, 17:14 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org