IOTA/IOTA-ES occultation update for (1690) Mayrhofer / TYC 0218-00252-1 event on 2008 May 10, 13:17 UT Visible from Indonesia Summary ------- On 2008 May 10 UT, the 32 km diameter asteroid (1690) Mayrhofer will occult a 9.9 mag star in the constellation Hydra for observers along a path across Indonesia. In the case of an occultation, the combined light of the asteroid and the star will drop by 7.0 mag to 16.9 mag (the magnitude of the asteroid) for at most 1.5 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: 24 * date and approx. time of event: 2008 May 10, 13:18 - 2008 May 10, 13:22 UT * midpoint of event [JD]: 2454597.05380833 * magnitude of target star: 9.9 * magnitude drop [mag]: 7.0 * estimated maximum duration [s]: 1.5 * Moon: 33 % sunlit, 18° distance * Sun: 79° distance * rough path description: Indonesia The occultation path -------------------- * approximate projected width [km]: 32 * 1 sigma uncertainty interval [path widths]: +/- 2.84 * 1 sigma uncertainty interval [seconds]: +/- 3.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .037 +/- .040) * 1 sigma uncertainty ellipse (major, minor, PA): ( .040", .037", 5° ) * approx speed of asteroid's shadow [km/s]: 21.9748 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 0218-00252-1 by 1690 Mayrhofer on 2008 May 10 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 69 0 0 - 2 6 3 13 18 14 78 311 0 - 2 14 49 - 1 57 18 - 3 4 39 - 1 7 36 70 0 0 - 2 6 31 13 18 19 77 308 -1 - 2 15 17 - 1 57 45 - 3 5 6 - 1 8 4 71 0 0 - 2 7 5 13 18 24 77 305 -2 - 2 15 51 - 1 58 19 - 3 5 40 - 1 8 38 72 0 0 - 2 7 45 13 18 29 76 303 -3 - 2 16 31 - 1 59 0 - 3 6 21 - 1 9 18 73 0 0 - 2 8 32 13 18 34 75 301 -4 - 2 17 18 - 1 59 47 - 3 7 8 - 1 10 5 74 0 0 - 2 9 25 13 18 39 74 299 -5 - 2 18 11 - 2 0 40 - 3 8 1 - 1 10 58 75 0 0 - 2 10 25 13 18 44 73 297 -6 - 2 19 11 - 2 1 39 - 3 9 1 - 1 11 57 76 0 0 - 2 11 31 13 18 49 72 296 -7 - 2 20 17 - 2 2 45 - 3 10 7 - 1 13 3 77 0 0 - 2 12 43 13 18 54 71 294 -8 - 2 21 29 - 2 3 57 - 3 11 19 - 1 14 15 78 0 0 - 2 14 2 13 18 59 70 293 -9 - 2 22 47 - 2 5 16 - 3 12 37 - 1 15 34 79 0 0 - 2 15 26 13 19 4 69 292 -10 - 2 24 12 - 2 6 41 - 3 14 2 - 1 16 58 80 0 0 - 2 16 57 13 19 9 68 291 -11 - 2 25 43 - 2 8 12 - 3 15 33 - 1 18 29 81 0 0 - 2 18 34 13 19 14 67 290 -12 - 2 27 20 - 2 9 49 - 3 17 11 - 1 20 6 82 0 0 - 2 20 18 13 19 19 66 290 -13 - 2 29 4 - 2 11 32 - 3 18 54 - 1 21 49 83 0 0 - 2 22 7 13 19 23 66 289 -14 - 2 30 53 - 2 13 22 - 3 20 44 - 1 23 39 84 0 0 - 2 24 3 13 19 28 65 288 -15 - 2 32 49 - 2 15 17 - 3 22 40 - 1 25 34 85 0 0 - 2 26 4 13 19 33 64 288 -16 - 2 34 50 - 2 17 19 - 3 24 41 - 1 27 35 86 0 0 - 2 28 12 13 19 37 63 287 -17 - 2 36 58 - 2 19 26 - 3 26 49 - 1 29 43 87 0 0 - 2 30 26 13 19 42 62 286 -18 - 2 39 12 - 2 21 40 - 3 29 3 - 1 31 56 88 0 0 - 2 32 45 13 19 47 61 286 -19 - 2 41 31 - 2 23 59 - 3 31 23 - 1 34 15 89 0 0 - 2 35 11 13 19 51 60 286 -20 - 2 43 57 - 2 26 25 - 3 33 48 - 1 36 41 90 0 0 - 2 37 42 13 19 56 59 285 -21 - 2 46 28 - 2 28 56 - 3 36 20 - 1 39 12 91 0 0 - 2 40 19 13 20 0 58 285 -22 - 2 49 5 - 2 31 33 - 3 38 57 - 1 41 48 92 0 0 - 2 43 2 13 20 4 57 284 -23 - 2 51 48 - 2 34 15 - 3 41 40 - 1 44 31 93 0 0 - 2 45 50 13 20 9 56 284 -24 - 2 54 36 - 2 37 4 - 3 44 29 - 1 47 19 94 0 0 - 2 48 44 13 20 13 55 284 -25 - 2 57 30 - 2 39 58 - 3 47 23 - 1 50 13 95 0 0 - 2 51 43 13 20 17 54 283 -26 - 3 0 30 - 2 42 57 - 3 50 23 - 1 53 12 96 0 0 - 2 54 48 13 20 21 53 283 -27 - 3 3 35 - 2 46 2 - 3 53 28 - 1 56 17 97 0 0 - 2 57 59 13 20 25 52 283 -28 - 3 6 45 - 2 49 13 - 3 56 39 - 1 59 27 98 0 0 - 3 1 15 13 20 29 51 282 -29 - 3 10 1 - 2 52 28 - 3 59 55 - 2 2 43 99 0 0 - 3 4 36 13 20 33 50 282 -29 - 3 13 22 - 2 55 49 - 4 3 16 - 2 6 3 100 0 0 - 3 8 2 13 20 37 49 282 -30 - 3 16 49 - 2 59 16 - 4 6 43 - 2 9 29 101 0 0 - 3 11 34 13 20 41 48 282 -31 - 3 20 20 - 3 2 47 - 4 10 14 - 2 13 1 102 0 0 - 3 15 10 13 20 45 47 282 -32 - 3 23 57 - 3 6 24 - 4 13 51 - 2 16 37 103 0 0 - 3 18 52 13 20 49 46 281 -33 - 3 27 38 - 3 10 5 - 4 17 33 - 2 20 18 104 0 0 - 3 22 38 13 20 52 45 281 -34 - 3 31 25 - 3 13 52 - 4 21 20 - 2 24 4 105 0 0 - 3 26 29 13 20 56 44 281 -35 - 3 35 16 - 3 17 43 - 4 25 11 - 2 27 55 106 0 0 - 3 30 26 13 21 0 43 281 -36 - 3 39 12 - 3 21 39 - 4 29 8 - 2 31 51 107 0 0 - 3 34 26 13 21 3 42 281 -37 - 3 43 13 - 3 25 40 - 4 33 9 - 2 35 52 108 0 0 - 3 38 32 13 21 6 41 280 -38 - 3 47 19 - 3 29 45 - 4 37 15 - 2 39 57 109 0 0 - 3 42 42 13 21 10 40 280 -39 - 3 51 29 - 3 33 55 - 4 41 25 - 2 44 7 110 0 0 - 3 46 56 13 21 13 39 280 -40 - 3 55 43 - 3 38 10 - 4 45 40 - 2 48 21 111 0 0 - 3 51 15 13 21 16 38 280 -41 - 4 0 2 - 3 42 28 - 4 49 59 - 2 52 39 112 0 0 - 3 55 38 13 21 19 37 280 -42 - 4 4 25 - 3 46 51 - 4 54 22 - 2 57 2 113 0 0 - 4 0 5 13 21 22 36 280 -43 - 4 8 52 - 3 51 19 - 4 58 50 - 3 1 29 114 0 0 - 4 4 37 13 21 25 35 280 -44 - 4 13 24 - 3 55 50 - 5 3 21 - 3 6 0 115 0 0 - 4 9 12 13 21 28 34 279 -45 - 4 17 59 - 4 0 25 - 5 7 57 - 3 10 35 116 0 0 - 4 13 51 13 21 31 32 279 -46 - 4 22 39 - 4 5 4 - 5 12 37 - 3 15 14 117 0 0 - 4 18 35 13 21 34 31 279 -47 - 4 27 22 - 4 9 48 - 5 17 20 - 3 19 57 118 0 0 - 4 23 21 13 21 37 30 279 -48 - 4 32 9 - 4 14 34 - 5 22 7 - 3 24 44 119 0 0 - 4 28 12 13 21 39 29 279 -49 - 4 36 59 - 4 19 25 - 5 26 58 - 3 29 34 120 0 0 - 4 33 6 13 21 42 28 279 -50 - 4 41 53 - 4 24 19 - 5 31 52 - 3 34 28 121 0 0 - 4 38 3 13 21 44 27 279 -51 - 4 46 51 - 4 29 16 - 5 36 50 - 3 39 25 122 0 0 - 4 43 4 13 21 46 26 279 -52 - 4 51 52 - 4 34 17 - 5 41 51 - 3 44 26 123 0 0 - 4 48 8 13 21 49 25 278 -53 - 4 56 56 - 4 39 21 - 5 46 55 - 3 49 29 124 0 0 - 4 53 16 13 21 51 24 278 -54 - 5 2 3 - 4 44 28 - 5 52 3 - 3 54 36 125 0 0 - 4 58 26 13 21 53 23 278 -55 - 5 7 13 - 4 49 38 - 5 57 13 - 3 59 46 126 0 0 - 5 3 39 13 21 55 22 278 -56 - 5 12 27 - 4 54 52 - 6 2 27 - 4 4 59 127 0 0 - 5 8 55 13 21 57 21 278 -57 - 5 17 43 - 5 0 8 - 6 7 43 - 4 10 15 128 0 0 - 5 14 14 13 21 59 20 278 -58 - 5 23 1 - 5 5 26 - 6 13 2 - 4 15 34 129 0 0 - 5 19 35 13 22 0 19 278 -58 - 5 28 23 - 5 10 48 - 6 18 23 - 4 20 55 130 0 0 - 5 24 59 13 22 2 18 278 -59 - 5 33 47 - 5 16 12 - 6 23 48 - 4 26 19 131 0 0 - 5 30 26 13 22 4 17 278 -60 - 5 39 13 - 5 21 38 - 6 29 14 - 4 31 45 132 0 0 - 5 35 54 13 22 5 16 277 -61 - 5 44 42 - 5 27 7 - 6 34 43 - 4 37 13 133 0 0 - 5 41 25 13 22 7 15 277 -62 - 5 50 13 - 5 32 37 - 6 40 14 - 4 42 44 134 0 0 - 5 46 58 13 22 8 14 277 -63 - 5 55 46 - 5 38 10 - 6 45 47 - 4 48 17 135 0 0 - 5 52 33 13 22 9 13 277 -64 - 6 1 21 - 5 43 45 - 6 51 22 - 4 53 52 136 0 0 - 5 58 10 13 22 10 12 277 -65 - 6 6 58 - 5 49 22 - 6 56 59 - 4 59 28 137 0 0 - 6 3 48 13 22 11 11 277 -66 - 6 12 36 - 5 55 1 - 7 2 38 - 5 5 7 138 0 0 - 6 9 29 13 22 12 10 277 -67 - 6 18 17 - 6 0 41 - 7 8 18 - 5 10 47 139 0 0 - 6 15 11 13 22 13 9 277 -68 - 6 23 58 - 6 6 23 - 7 14 0 - 5 16 29 140 0 0 - 6 20 54 13 22 14 8 277 -69 - 6 29 42 - 6 12 6 - 7 19 44 - 5 22 12 141 0 0 - 6 26 38 13 22 15 7 276 -69 - 6 35 26 - 6 17 51 - 7 25 29 - 5 27 56 142 0 0 - 6 32 24 13 22 15 6 276 -70 - 6 41 12 - 6 23 37 - 7 31 15 - 5 33 42 143 0 0 - 6 38 11 13 22 16 5 276 -71 - 6 46 59 - 6 29 23 - 7 37 2 - 5 39 29 144 0 0 - 6 43 59 13 22 16 4 276 -72 - 6 52 47 - 6 35 11 - 7 42 50 - 5 45 17 145 0 0 - 6 49 48 13 22 17 3 276 -73 - 6 58 36 - 6 41 0 - 7 48 39 - 5 51 6 146 0 0 - 6 55 38 13 22 17 2 276 -74 - 7 4 26 - 6 46 50 - 7 54 28 - 5 56 55 147 0 0 - 7 1 28 13 22 17 1 276 -74 - 7 10 16 - 6 52 40 - 8 0 19 - 6 2 45 148 0 0 - 7 7 19 13 22 17 0 276 -75 - 7 16 7 - 6 58 31 - 8 6 10 - 6 8 36 Uncertainty in time = +/- 4 secs [Prediction of 2008 Mar 29.0] Data for the target star ------------------------ * name: TYC 0218-00252-1 * constellation : Hydra * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 08 32 56.9295 DE: +05 33 55.808 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .020, .033 ) * V mag [mag]: 9.9 * B mag [mag]: 10.5 * Apparent position with proper motion RA(deg): 128.3490817730 DE(deg): 5.5366742570 * Equation of equinoxes (radians) : 0.000041000739596 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1690) Mayrhofer approx. diameter [km]: 32 approx. diameter ["]: .014 distance from Earth [AU]: 3.18200 * orbital information: orbit source: Preston date of fit: 2008 Mar 28 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 908 number of rejected observations: 23 time covered by the observations: 1932 Nov 28 - 2008 Jan 18 1 sigma uncertainty ellipse (major, minor, PA): 0.031, 0.023, 106° remarks: * orbital elements for (1690) Mayrhofer : Mean anomaly = 108.33464143 deg Arg. of pericenter = 158.86140151 deg Long. of node = 230.53168496 deg Inclination = 13.04379083 deg Eccentricity = 0.09661144 Semimajor axis = 3.03920079 AU Perihelion dist = 2.74557922 AU Mag: H = 11.06, G = 0.15 Epoch of elements : MJD 54596.55400000 TDT (2008 May 10.554) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 10 1690 Mayrhofer 13h 17.5m UT 9.9 8 32 56.930 5 33 55.81TYC 0218-00252-1 10.5 16.9 32 1.5 3.182 2.296 0.29 60.1546 5.565 -20.27 17.81 13.2914 -0.00002 -0.13282 12.40276 0.10589 0.00537 -0.00166 2000 107.1154512008 5 4.00000158.861402230.531685 13.0437910.09661144 3.0392008 2.745579210.9 5.00.15 RATE 1.8602230 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.040 0.037 5 3.84 0.039 0 54554.5020080510_0252-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 31, 04:26 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org