IOTA/IOTA-ES occultation update for (37) Fides / TYC 5537-01021-1 event on 2012 Aug 03, 01:49 UT Visible from Chile Summary ------- On 2012 Aug 03 UT, the 103 km diameter asteroid (37) Fides will occult a 9.3 mag star in the constellation Virgo for observers along a path across Chile. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.8 mag to 13.1 mag (the magnitude of the asteroid) for at most 4.0 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: 89 * date and approx. time of event: 2012 Aug 03, 01:50 - 2012 Aug 03, 01:53 UT * geocentric midpoint of event [JD]: 2456142.5760125 * magnitude of target star: 9.3 * magnitude drop [mag]: 3.8 * estimated maximum duration [s]: 4.0 * Moon: 99 % sunlit, 122° distance * Sun: 70° distance * rough path description: Chile The occultation path -------------------- * approximate projected width [km]: 104 * 1 sigma uncertainty interval [path widths]: +/- 0.54 * 1 sigma uncertainty interval [seconds]: +/- 1.8 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .020 +/- .024) * 1 sigma uncertainty ellipse (major, minor, PA): ( .024", .020", 1° ) * approx speed of asteroid's shadow [km/s]: 25.8199 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5537-01021-1 by 37 Fides on 2012 Aug 3 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 -124 0 0 -24 4 51 1 50 51 68 309 0 -24 34 39 -23 35 4 -25 6 54 -23 2 56 -123 0 0 -24 23 46 1 50 55 67 307 -1 -24 53 32 -23 54 3 -25 25 43 -23 21 58 -122 0 0 -24 42 20 1 50 59 66 306 -2 -25 12 3 -24 12 40 -25 44 10 -23 40 39 -121 0 0 -25 0 32 1 51 3 66 305 -3 -25 30 11 -24 30 55 -26 2 16 -23 58 58 -120 0 0 -25 18 22 1 51 7 65 304 -4 -25 47 59 -24 48 48 -26 19 59 -24 16 55 -119 0 0 -25 35 51 1 51 10 64 303 -5 -26 5 23 -25 6 20 -26 37 21 -24 34 29 -118 0 0 -25 52 56 1 51 14 63 302 -6 -26 22 26 -25 23 29 -26 54 20 -24 51 42 -117 0 0 -26 9 40 1 51 18 62 301 -7 -26 39 6 -25 40 15 -27 10 57 -25 8 32 -116 0 0 -26 26 1 1 51 21 61 300 -8 -26 55 24 -25 56 39 -27 27 11 -25 24 59 -115 0 0 -26 41 59 1 51 25 60 300 -9 -27 11 20 -26 12 41 -27 43 3 -25 41 4 -114 0 0 -26 57 35 1 51 29 59 299 -10 -27 26 52 -26 28 20 -27 58 33 -25 56 46 -113 0 0 -27 12 48 1 51 32 58 298 -11 -27 42 2 -26 43 36 -28 13 39 -26 12 5 -112 0 0 -27 27 38 1 51 36 57 297 -12 -27 56 50 -26 58 29 -28 28 23 -26 27 2 -111 0 0 -27 42 6 1 51 39 56 296 -13 -28 11 14 -27 12 59 -28 42 45 -26 41 35 -110 0 0 -27 56 10 1 51 42 55 296 -13 -28 25 16 -27 27 7 -28 56 43 -26 55 46 -109 0 0 -28 9 52 1 51 46 55 295 -14 -28 38 54 -27 40 51 -29 10 19 -27 9 33 -108 0 0 -28 23 10 1 51 49 54 294 -15 -28 52 10 -27 54 12 -29 23 31 -27 22 57 -107 0 0 -28 36 6 1 51 52 53 294 -16 -29 5 3 -28 7 10 -29 36 21 -27 35 58 -106 0 0 -28 48 38 1 51 55 52 293 -17 -29 17 32 -28 19 45 -29 48 48 -27 48 36 -105 0 0 -29 0 47 1 51 58 51 292 -18 -29 29 39 -28 31 57 -30 0 52 -28 0 51 -104 0 0 -29 12 33 1 52 1 50 291 -19 -29 41 23 -28 43 46 -30 12 32 -28 12 43 -103 0 0 -29 23 57 1 52 4 49 291 -20 -29 52 43 -28 55 12 -30 23 50 -28 24 11 -102 0 0 -29 34 57 1 52 7 48 290 -21 -30 3 41 -29 6 14 -30 34 45 -28 35 16 -101 0 0 -29 45 34 1 52 10 47 290 -22 -30 14 16 -29 16 54 -30 45 17 -28 45 58 -100 0 0 -29 55 48 1 52 13 47 289 -23 -30 24 27 -29 27 10 -30 55 26 -28 56 17 - 99 0 0 -30 5 38 1 52 16 46 288 -23 -30 34 16 -29 37 3 -31 5 13 -29 6 12 - 98 0 0 -30 15 6 1 52 19 45 288 -24 -30 43 41 -29 46 33 -31 14 36 -29 15 44 - 97 0 0 -30 24 11 1 52 21 44 287 -25 -30 52 44 -29 55 40 -31 23 36 -29 24 53 - 96 0 0 -30 32 52 1 52 24 43 286 -26 -31 1 23 -30 4 23 -31 32 14 -29 33 39 - 95 0 0 -30 41 11 1 52 26 42 286 -27 -31 9 40 -30 12 44 -31 40 28 -29 42 2 - 94 0 0 -30 49 7 1 52 29 41 285 -28 -31 17 34 -30 20 41 -31 48 20 -29 50 1 - 93 0 0 -30 56 39 1 52 31 40 285 -29 -31 25 5 -30 28 16 -31 55 49 -29 57 38 - 92 0 0 -31 3 49 1 52 34 40 284 -30 -31 32 13 -30 35 27 -32 2 55 -30 4 51 - 91 0 0 -31 10 36 1 52 36 39 283 -30 -31 38 58 -30 42 16 -32 9 39 -30 11 41 - 90 0 0 -31 17 0 1 52 39 38 283 -31 -31 45 21 -30 48 41 -32 16 0 -30 18 8 - 89 0 0 -31 23 1 1 52 41 37 282 -32 -31 51 20 -30 54 44 -32 21 58 -30 24 12 - 88 0 0 -31 28 39 1 52 43 36 282 -33 -31 56 57 -31 0 23 -32 27 33 -30 29 53 - 87 0 0 -31 33 55 1 52 45 35 281 -34 -32 2 12 -31 5 40 -32 32 46 -30 35 11 - 86 0 0 -31 38 48 1 52 48 34 280 -35 -32 7 3 -31 10 34 -32 37 36 -30 40 7 - 85 0 0 -31 43 17 1 52 50 33 280 -36 -32 11 32 -31 15 5 -32 42 4 -30 44 39 - 84 0 0 -31 47 25 1 52 52 33 279 -37 -32 15 38 -31 19 13 -32 46 9 -30 48 48 - 83 0 0 -31 51 9 1 52 54 32 279 -37 -32 19 22 -31 22 58 -32 49 52 -30 52 34 - 82 0 0 -31 54 31 1 52 56 31 278 -38 -32 22 43 -31 26 21 -32 53 12 -30 55 58 - 81 0 0 -31 57 30 1 52 58 30 278 -39 -32 25 41 -31 29 21 -32 56 10 -30 58 58 - 80 0 0 -32 0 7 1 52 59 29 277 -40 -32 28 17 -31 31 58 -32 58 45 -31 1 36 - 79 0 0 -32 2 21 1 53 1 28 276 -41 -32 30 30 -31 34 13 -33 0 58 -31 3 51 - 78 0 0 -32 4 12 1 53 3 28 276 -42 -32 32 21 -31 36 4 -33 2 48 -31 5 44 - 77 0 0 -32 5 41 1 53 5 27 275 -42 -32 33 50 -31 37 34 -33 4 16 -31 7 13 - 76 0 0 -32 6 47 1 53 6 26 275 -43 -32 34 56 -31 38 40 -33 5 22 -31 8 20 - 75 0 0 -32 7 31 1 53 8 25 274 -44 -32 35 39 -31 39 24 -33 6 5 -31 9 4 - 74 0 0 -32 7 52 1 53 9 24 274 -45 -32 36 1 -31 39 45 -33 6 26 -31 9 25 - 73 0 0 -32 7 51 1 53 11 23 273 -46 -32 35 59 -31 39 44 -33 6 25 -31 9 24 - 72 0 0 -32 7 27 1 53 12 22 273 -47 -32 35 36 -31 39 20 -33 6 2 -31 9 0 - 71 0 0 -32 6 41 1 53 14 22 272 -48 -32 34 50 -31 38 34 -33 5 16 -31 8 13 - 70 0 0 -32 5 32 1 53 15 21 271 -48 -32 33 41 -31 37 25 -33 4 8 -31 7 4 - 69 0 0 -32 4 1 1 53 16 20 271 -49 -32 32 11 -31 35 53 -33 2 38 -31 5 32 - 68 0 0 -32 2 7 1 53 18 19 270 -50 -32 30 17 -31 33 59 -33 0 45 -31 3 37 - 67 0 0 -31 59 51 1 53 19 18 270 -51 -32 28 2 -31 31 42 -32 58 30 -31 1 20 - 66 0 0 -31 57 13 1 53 20 17 269 -52 -32 25 24 -31 29 3 -32 55 53 -30 58 40 - 65 0 0 -31 54 12 1 53 21 16 269 -53 -32 22 24 -31 26 2 -32 52 54 -30 55 38 - 64 0 0 -31 50 49 1 53 22 16 268 -53 -32 19 2 -31 22 38 -32 49 32 -30 52 13 - 63 0 0 -31 47 3 1 53 23 15 268 -54 -32 15 17 -31 18 51 -32 45 49 -30 48 25 - 62 0 0 -31 42 55 1 53 24 14 267 -55 -32 11 10 -31 14 42 -32 41 43 -30 44 15 - 61 0 0 -31 38 25 1 53 25 13 267 -56 -32 6 41 -31 10 10 -32 37 15 -30 39 43 - 60 0 0 -31 33 32 1 53 26 12 266 -57 -32 1 49 -31 5 16 -32 32 24 -30 34 47 - 59 0 0 -31 28 17 1 53 26 11 266 -58 -31 56 35 -31 0 0 -32 27 12 -30 29 29 - 58 0 0 -31 22 39 1 53 27 10 265 -58 -31 50 59 -30 54 21 -32 21 37 -30 23 49 - 57 0 0 -31 16 39 1 53 28 10 264 -59 -31 45 0 -30 48 20 -32 15 40 -30 17 46 - 56 0 0 -31 10 17 1 53 28 9 264 -60 -31 38 40 -30 41 56 -32 9 21 -30 11 20 - 55 0 0 -31 3 32 1 53 29 8 263 -61 -31 31 56 -30 35 9 -32 2 40 -30 4 32 - 54 0 0 -30 56 25 1 53 29 7 263 -62 -31 24 51 -30 28 1 -31 55 36 -29 57 22 - 53 0 0 -30 48 55 1 53 30 6 262 -63 -31 17 23 -30 20 29 -31 48 10 -29 49 49 - 52 0 0 -30 41 3 1 53 30 5 262 -64 -31 9 33 -30 12 36 -31 40 22 -29 41 53 - 51 0 0 -30 32 49 1 53 30 4 261 -64 -31 1 21 -30 4 19 -31 32 12 -29 33 35 - 50 0 0 -30 24 13 1 53 31 3 261 -65 -30 52 46 -29 55 41 -31 23 39 -29 24 54 - 49 0 0 -30 15 14 1 53 31 3 260 -66 -30 43 49 -29 46 40 -31 14 45 -29 15 51 - 48 0 0 -30 5 53 1 53 31 2 260 -67 -30 34 30 -29 37 17 -31 5 28 -29 6 26 - 47 0 0 -29 56 9 1 53 31 1 259 -68 -30 24 49 -29 27 31 -30 55 49 -28 56 38 Uncertainty in time = +/- 2 secs Prediction of 2012 Jun 6.0 Data for the target star ------------------------ * name: TYC 5537-01021-1 * constellation : Virgo * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 13 14 42.9165 DE: -09 33 21.512 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .019, .024 ) * V mag [mag]: 9.3 * B mag [mag]: 10.0 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (37) Fides approx. diameter [km]: 103 approx. diameter ["]: .044 distance from Earth [AU]: 3.20700 * orbital information: orbit source: Preston date of fit: 2012 Jun 06 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1493 number of rejected observations: 163 time covered by the observations: 1900 Feb 24 - 2012 May 29 1 sigma uncertainty ellipse (major, minor, PA): 0.007, 0.005, 116° remarks: * orbital elements for (37) Fides : Mean anomaly = 137.86427333 deg Arg. of pericenter = 62.71501454 deg Long. of node = 7.32973297 deg Inclination = 3.07292630 deg Eccentricity = 0.17366683 Semimajor axis = 2.64353506 AU Perihelion dist = 2.18444069 AU Mag: H = 7.39, G = 0.24 Epoch of elements : MJD 56142.07600000 TDT (2012 Aug 03.076) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Aug 3 37 Fides 1h 49.5m UT 9.3 13 14 42.917- 9 33 21.51TYC 5537-01021-1 10.0 13.1 103 4.0 3.207 2.497 -15.24 -140.7397 -9.552 154.18 17.43 1.8243 -0.04730 -0.12450 13.47176 -5.55852 0.00485 -0.00203 2000 137.3882222012 8 1.00000 62.715015 7.329733 3.0729260.17366683 2.6435351 2.1844407 7.3 5.00.24 RATE 2.2931180 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.024 0.020 1 1.54 0.024 0 0-5-2 056084.0020120803_1021-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Jun 06, 04:28 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org