IOTA/IOTA-ES occultation update for (429) Lotis / TYC 0801-01598-1 event on 2008 May 20, 02:47 UT Visible from Peru Summary ------- On 2008 May 20 UT, the 70 km diameter asteroid (429) Lotis will occult a 8.7 mag star in the constellation Cancer for observers along a path across Peru. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.6 mag to 15.3 mag (the magnitude of the asteroid) for at most 2.5 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, TMO astrometry for the asteroid kindly provided by Bill Owen, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: . The event at a glimpse ---------------------- * Rank: 67 * date and approx. time of event: 2008 May 20, 02:48 - 2008 May 20, 02:51 UT * midpoint of event [JD]: 2454606.61645833 * magnitude of target star: 8.7 * magnitude drop [mag]: 6.6 * estimated maximum duration [s]: 2.5 * Moon: 100 % sunlit, 110° distance * Sun: 70° distance * rough path description: Peru Additional comments ------------------- 10" double star The occultation path -------------------- * approximate projected width [km]: 71 * 1 sigma uncertainty interval [path widths]: +/- 0.89 * 1 sigma uncertainty interval [seconds]: +/- 2.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .030 +/- .029) * 1 sigma uncertainty ellipse (major, minor, PA): ( .030", .029", 94° ) * approx speed of asteroid's shadow [km/s]: 27.3559 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 0801-01598-1 by 429 Lotis on 2008 May 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 -134 0 0 - 3 24 33 2 48 56 68 308 0 - 3 44 8 - 3 4 59 - 4 19 4 - 2 30 11 -133 0 0 - 3 34 13 2 49 0 67 307 -1 - 3 53 49 - 3 14 38 - 4 28 46 - 2 39 50 -132 0 0 - 3 44 2 2 49 4 66 305 -2 - 4 3 38 - 3 24 27 - 4 38 36 - 2 49 38 -131 0 0 - 3 53 59 2 49 8 66 304 -3 - 4 13 36 - 3 34 24 - 4 48 34 - 2 59 34 -130 0 0 - 4 4 5 2 49 12 65 303 -4 - 4 23 42 - 3 44 29 - 4 58 41 - 3 9 39 -129 0 0 - 4 14 19 2 49 16 64 302 -5 - 4 33 57 - 3 54 42 - 5 8 56 - 3 19 51 -128 0 0 - 4 24 41 2 49 20 63 302 -6 - 4 44 19 - 4 5 4 - 5 19 19 - 3 30 12 -127 0 0 - 4 35 10 2 49 23 62 301 -7 - 4 54 49 - 4 15 33 - 5 29 50 - 3 40 40 -126 0 0 - 4 45 47 2 49 27 61 300 -8 - 5 5 26 - 4 26 9 - 5 40 28 - 3 51 16 -125 0 0 - 4 56 31 2 49 31 60 299 -9 - 5 16 10 - 4 36 53 - 5 51 13 - 4 1 59 -124 0 0 - 5 7 22 2 49 35 59 299 -10 - 5 27 2 - 4 47 44 - 6 2 5 - 4 12 49 -123 0 0 - 5 18 20 2 49 38 58 298 -11 - 5 38 0 - 4 58 41 - 6 13 4 - 4 23 46 -122 0 0 - 5 29 25 2 49 42 57 298 -12 - 5 49 5 - 5 9 46 - 6 24 10 - 4 34 50 -121 0 0 - 5 40 36 2 49 45 56 297 -13 - 6 0 17 - 5 20 56 - 6 35 22 - 4 46 0 -120 0 0 - 5 51 53 2 49 49 55 296 -14 - 6 11 34 - 5 32 13 - 6 46 40 - 4 57 16 -119 0 0 - 6 3 16 2 49 52 54 296 -15 - 6 22 58 - 5 43 36 - 6 58 4 - 5 8 38 -118 0 0 - 6 14 45 2 49 56 53 295 -17 - 6 34 27 - 5 55 4 - 7 9 34 - 5 20 6 -117 0 0 - 6 26 19 2 49 59 52 295 -18 - 6 46 1 - 6 6 38 - 7 21 9 - 5 31 39 -116 0 0 - 6 37 58 2 50 2 51 295 -19 - 6 57 41 - 6 18 17 - 7 32 49 - 5 43 18 -115 0 0 - 6 49 43 2 50 6 50 294 -20 - 7 9 25 - 6 30 1 - 7 44 34 - 5 55 1 -114 0 0 - 7 1 32 2 50 9 49 294 -21 - 7 21 15 - 6 41 50 - 7 56 24 - 6 6 49 -113 0 0 - 7 13 25 2 50 12 48 293 -22 - 7 33 8 - 6 53 43 - 8 8 18 - 6 18 42 -112 0 0 - 7 25 23 2 50 15 47 293 -23 - 7 45 6 - 7 5 40 - 8 20 17 - 6 30 39 -111 0 0 - 7 37 24 2 50 18 46 293 -24 - 7 57 8 - 7 17 42 - 8 32 19 - 6 42 40 -110 0 0 - 7 49 30 2 50 21 45 292 -25 - 8 9 14 - 7 29 47 - 8 44 25 - 6 54 44 -109 0 0 - 8 1 38 2 50 24 44 292 -26 - 8 21 23 - 7 41 55 - 8 56 34 - 7 6 53 -108 0 0 - 8 13 50 2 50 27 43 292 -27 - 8 33 35 - 7 54 7 - 9 8 47 - 7 19 4 -107 0 0 - 8 26 5 2 50 30 42 291 -28 - 8 45 50 - 8 6 22 - 9 21 2 - 7 31 18 -106 0 0 - 8 38 23 2 50 33 41 291 -29 - 8 58 8 - 8 18 39 - 9 33 20 - 7 43 35 -105 0 0 - 8 50 43 2 50 35 40 291 -30 - 9 10 28 - 8 30 59 - 9 45 41 - 7 55 55 -104 0 0 - 9 3 5 2 50 38 39 291 -31 - 9 22 50 - 8 43 21 - 9 58 3 - 8 8 17 -103 0 0 - 9 15 29 2 50 41 38 290 -32 - 9 35 14 - 8 55 45 -10 10 28 - 8 20 40 -102 0 0 - 9 27 55 2 50 43 37 290 -33 - 9 47 40 - 9 8 10 -10 22 54 - 8 33 6 -101 0 0 - 9 40 22 2 50 46 36 290 -34 -10 0 7 - 9 20 37 -10 35 21 - 8 45 33 -100 0 0 - 9 52 50 2 50 48 35 289 -35 -10 12 36 - 9 33 6 -10 47 49 - 8 58 1 - 99 0 0 -10 5 19 2 50 51 34 289 -36 -10 25 5 - 9 45 35 -11 0 19 - 9 10 29 - 98 0 0 -10 17 49 2 50 53 33 289 -37 -10 37 35 - 9 58 4 -11 12 49 - 9 22 59 - 97 0 0 -10 30 19 2 50 55 32 289 -38 -10 50 5 -10 10 34 -11 25 19 - 9 35 29 - 96 0 0 -10 42 49 2 50 57 31 288 -39 -11 2 35 -10 23 5 -11 37 49 - 9 47 59 - 95 0 0 -10 55 19 2 51 0 30 288 -40 -11 15 5 -10 35 35 -11 50 19 -10 0 29 - 94 0 0 -11 7 49 2 51 2 29 288 -41 -11 27 34 -10 48 4 -12 2 49 -10 12 59 - 93 0 0 -11 20 18 2 51 4 28 288 -42 -11 40 3 -11 0 33 -12 15 17 -10 25 28 - 92 0 0 -11 32 46 2 51 5 27 287 -43 -11 52 31 -11 13 1 -12 27 45 -10 37 56 - 91 0 0 -11 45 13 2 51 7 26 287 -44 -12 4 58 -11 25 28 -12 40 12 -10 50 23 - 90 0 0 -11 57 38 2 51 9 25 287 -45 -12 17 24 -11 37 54 -12 52 37 -11 2 49 - 89 0 0 -12 10 2 2 51 11 24 287 -46 -12 29 47 -11 50 18 -13 5 1 -11 15 13 - 88 0 0 -12 22 24 2 51 12 23 286 -47 -12 42 9 -12 2 40 -13 17 22 -11 27 35 - 87 0 0 -12 34 44 2 51 14 22 286 -48 -12 54 29 -12 15 0 -13 29 42 -11 39 55 - 86 0 0 -12 47 1 2 51 16 21 286 -49 -13 6 46 -12 27 17 -13 41 59 -11 52 13 - 85 0 0 -12 59 16 2 51 17 20 286 -50 -13 19 1 -12 39 32 -13 54 13 -12 4 28 - 84 0 0 -13 11 28 2 51 18 19 285 -51 -13 31 12 -12 51 44 -14 6 24 -12 16 41 - 83 0 0 -13 23 36 2 51 20 18 285 -52 -13 43 21 -13 3 53 -14 18 33 -12 28 50 - 82 0 0 -13 35 42 2 51 21 17 285 -53 -13 55 26 -13 15 59 -14 30 37 -12 40 56 - 81 0 0 -13 47 43 2 51 22 16 285 -54 -14 7 28 -13 28 1 -14 42 39 -12 52 58 - 80 0 0 -13 59 41 2 51 23 15 284 -55 -14 19 25 -13 39 59 -14 54 36 -13 4 57 - 79 0 0 -14 11 35 2 51 24 14 284 -56 -14 31 19 -13 51 53 -15 6 29 -13 16 52 - 78 0 0 -14 23 25 2 51 25 13 284 -57 -14 43 9 -14 3 43 -15 18 18 -13 28 42 - 77 0 0 -14 35 10 2 51 26 12 284 -58 -14 54 54 -14 15 29 -15 30 3 -13 40 28 - 76 0 0 -14 46 51 2 51 27 11 283 -59 -15 6 34 -14 27 10 -15 41 43 -13 52 9 - 75 0 0 -14 58 27 2 51 28 10 283 -60 -15 18 9 -14 38 45 -15 53 18 -14 3 46 - 74 0 0 -15 9 57 2 51 28 9 283 -61 -15 29 40 -14 50 16 -16 4 47 -14 15 17 - 73 0 0 -15 21 23 2 51 29 8 283 -62 -15 41 4 -15 1 42 -16 16 12 -14 26 43 - 72 0 0 -15 32 42 2 51 29 7 282 -63 -15 52 24 -15 13 2 -16 27 30 -14 38 4 - 71 0 0 -15 43 56 2 51 30 6 282 -64 -16 3 37 -15 24 16 -16 38 43 -14 49 19 - 70 0 0 -15 55 4 2 51 30 5 282 -65 -16 14 45 -15 35 25 -16 49 51 -15 0 28 - 69 0 0 -16 6 6 2 51 30 4 281 -66 -16 25 47 -15 46 27 -17 0 51 -15 11 31 - 68 0 0 -16 17 2 2 51 31 3 281 -67 -16 36 42 -15 57 23 -17 11 46 -15 22 28 - 67 0 0 -16 27 51 2 51 31 2 281 -68 -16 47 31 -16 8 13 -17 22 34 -15 33 18 - 66 0 0 -16 38 34 2 51 31 1 281 -69 -16 58 13 -16 18 55 -17 33 16 -15 44 1 - 65 0 0 -16 49 9 2 51 31 0 280 -70 -17 8 48 -16 29 31 .. .. .. -15 54 38 Uncertainty in time = +/- 2 secs [Prediction of 2008 Apr 9.0] Data for the target star ------------------------ * name: TYC 0801-01598-1 * constellation : Cancer * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 08 35 54.4975 DE: +09 54 32.738 * position source: mpos:TYC pm:TYC * standard error: RA,DE ["]: ( .026, .027 ) * V mag [mag]: 8.7 * B mag [mag]: 9.3 * Apparent position with proper motion RA(deg): 129.0913418493 DE(deg): 9.8803228426 * Equation of equinoxes (radians) : 0.000039771837949 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (429) Lotis approx. diameter [km]: 70 approx. diameter ["]: .033 distance from Earth [AU]: 2.92000 * orbital information: orbit source: Preston date of fit: 2008 Apr 08 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 1018 number of rejected observations: 88 time covered by the observations: 1901 Oct 12 - 2008 Apr 01 1 sigma uncertainty ellipse (major, minor, PA): 0.015, 0.011, 104° remarks: * orbital elements for (429) Lotis : Mean anomaly = 107.55418124 deg Arg. of pericenter = 168.65508348 deg Long. of node = 220.03900483 deg Inclination = 9.52657867 deg Eccentricity = 0.12363137 Semimajor axis = 2.60734701 AU Perihelion dist = 2.28499711 AU Mag: H = 9.94, G = 0.15 Epoch of elements : MJD 54606.11600000 TDT (2008 May 20.116) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 20 429 Lotis 2h 47.7m UT 8.7 8 35 54.498 9 54 32.74TYC 0801-01598-1 9.3 15.3 70 2.5 2.920 3.129 -4.93 -151.0853 9.910 137.21 20.04 2.7950 -0.02080 -0.18793 15.35350 -1.63611 0.00496 -0.00159 2000 106.1224112008 514.00000168.655083220.039005 9.5265790.12363137 2.6073470 2.2849971 9.8 5.00.15 RATE 2.3410240 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.030 0.029 94 1.89 0.029 0 54565.5020080520_1598-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 13, 03:27 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org