IOTA/IOTA-ES occultation update for (1388) Aphrodite / TYC 5561-00665-1 event on 2012 Aug 10, 22:52 UT Visible from Brazil Summary ------- On 2012 Aug 10 UT, the 23 km diameter asteroid (1388) Aphrodite will occult a 10.0 mag star in the constellation Virgo for observers along a path across Brazil. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.6 mag to 16.6 mag (the magnitude of the asteroid) for at most 1.0 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: 26 * date and approx. time of event: 2012 Aug 10, 22:53 - 2012 Aug 10, 22:56 UT * geocentric midpoint of event [JD]: 2456150.4528875 * magnitude of target star: 10.0 * magnitude drop [mag]: 6.6 * estimated maximum duration [s]: 1.0 * Moon: 39 % sunlit, 155° distance * Sun: 78° distance * rough path description: Brazil The occultation path -------------------- * approximate projected width [km]: 23 * 1 sigma uncertainty interval [path widths]: +/- 2.60 * 1 sigma uncertainty interval [seconds]: +/- 3.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .035 +/- .029) * 1 sigma uncertainty ellipse (major, minor, PA): ( .036", .028", 108° ) * approx speed of asteroid's shadow [km/s]: 22.4537 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5561-00665-1 by 1388 Aphrodite on 2012 Aug 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 - 75 0 0 -13 46 5 22 53 8 76 267 -1 -13 52 58 -13 39 13 -14 28 41 -13 3 26 - 74 0 0 -14 12 6 22 53 13 75 269 -2 -14 18 57 -14 5 15 -14 54 34 -13 29 34 - 73 0 0 -14 37 36 22 53 18 74 270 -3 -14 44 26 -14 30 46 -15 19 57 -13 55 12 - 72 0 0 -15 2 36 22 53 23 73 271 -4 -15 9 25 -14 55 47 -15 44 49 -14 20 19 - 71 0 0 -15 27 4 22 53 28 72 272 -5 -15 33 52 -15 20 17 -16 9 10 -14 44 55 - 70 0 0 -15 51 2 22 53 33 71 273 -6 -15 57 48 -15 44 15 -16 33 0 -15 8 59 - 69 0 0 -16 14 27 22 53 38 70 274 -7 -16 21 13 -16 7 42 -16 56 18 -15 32 33 - 68 0 0 -16 37 22 22 53 43 69 274 -8 -16 44 6 -16 30 38 -17 19 6 -15 55 34 - 67 0 0 -16 59 45 22 53 48 68 275 -9 -17 6 27 -16 53 1 -17 41 21 -16 18 4 - 66 0 0 -17 21 35 22 53 53 67 275 -10 -17 28 17 -17 14 54 -18 3 5 -16 40 2 - 65 0 0 -17 42 54 22 53 57 66 275 -11 -17 49 35 -17 36 14 -18 24 17 -17 1 28 - 64 0 0 -18 3 41 22 54 2 65 276 -12 -18 10 21 -17 57 2 -18 44 57 -17 22 22 - 63 0 0 -18 23 56 22 54 7 64 276 -13 -18 30 35 -18 17 18 -19 5 6 -17 42 44 - 62 0 0 -18 43 39 22 54 11 63 276 -14 -18 50 17 -18 37 2 -19 24 42 -18 2 33 - 61 0 0 -19 2 50 22 54 16 62 276 -15 -19 9 27 -18 56 14 -19 43 46 -18 21 51 - 60 0 0 -19 21 29 22 54 20 61 276 -16 -19 28 4 -19 14 54 -20 2 18 -18 40 36 - 59 0 0 -19 39 36 22 54 25 60 276 -17 -19 46 10 -19 33 1 -20 20 19 -18 58 49 - 58 0 0 -19 57 10 22 54 29 59 276 -18 -20 3 43 -19 50 37 -20 37 47 -19 16 30 - 57 0 0 -20 14 12 22 54 33 58 276 -19 -20 20 45 -20 7 40 -20 54 43 -19 33 38 - 56 0 0 -20 30 42 22 54 37 57 276 -20 -20 37 14 -20 24 11 -21 11 7 -19 50 14 - 55 0 0 -20 46 41 22 54 42 57 276 -21 -20 53 11 -20 40 10 -21 27 0 -20 6 18 - 54 0 0 -21 2 7 22 54 46 56 276 -22 -21 8 36 -20 55 37 -21 42 20 -20 21 50 - 53 0 0 -21 17 1 22 54 50 55 276 -23 -21 23 30 -21 10 32 -21 57 9 -20 36 50 - 52 0 0 -21 31 23 22 54 54 54 275 -24 -21 37 51 -21 24 56 -22 11 26 -20 51 17 - 51 0 0 -21 45 14 22 54 58 53 275 -25 -21 51 41 -21 38 47 -22 25 12 -21 5 13 - 50 0 0 -21 58 33 22 55 1 52 275 -26 -22 4 59 -21 52 6 -22 38 25 -21 18 37 - 49 0 0 -22 11 20 22 55 5 51 275 -27 -22 17 45 -22 4 54 -22 51 8 -21 31 28 - 48 0 0 -22 23 35 22 55 9 50 275 -28 -22 30 0 -22 17 10 -23 3 19 -21 43 48 - 47 0 0 -22 35 19 22 55 12 49 274 -29 -22 41 43 -22 28 55 -23 14 58 -21 55 37 - 46 0 0 -22 46 31 22 55 16 48 274 -30 -22 52 55 -22 40 8 -23 26 6 -22 6 54 - 45 0 0 -22 57 12 22 55 19 47 274 -31 -23 3 35 -22 50 50 -23 36 43 -22 17 39 - 44 0 0 -23 7 22 22 55 23 46 274 -32 -23 13 44 -23 1 0 -23 46 49 -22 27 52 - 43 0 0 -23 17 1 22 55 26 45 273 -33 -23 23 22 -23 10 39 -23 56 24 -22 37 35 - 42 0 0 -23 26 8 22 55 30 44 273 -34 -23 32 29 -23 19 47 -24 5 27 -22 46 45 - 41 0 0 -23 34 44 22 55 33 43 273 -35 -23 41 5 -23 28 24 -24 14 0 -22 55 25 - 40 0 0 -23 42 50 22 55 36 42 272 -36 -23 49 9 -23 36 30 -24 22 3 -23 3 34 - 39 0 0 -23 50 24 22 55 39 41 272 -36 -23 56 43 -23 44 5 -24 29 34 -23 11 11 - 38 0 0 -23 57 28 22 55 42 40 272 -37 -24 3 46 -23 51 9 -24 36 35 -23 18 17 - 37 0 0 -24 4 1 22 55 45 39 271 -38 -24 10 19 -23 57 42 -24 43 5 -23 24 53 - 36 0 0 -24 10 3 22 55 48 39 271 -39 -24 16 21 -24 3 45 -24 49 5 -23 30 57 - 35 0 0 -24 15 34 22 55 51 38 271 -40 -24 21 52 -24 9 17 -24 54 34 -23 36 31 - 34 0 0 -24 20 35 22 55 54 37 270 -41 -24 26 53 -24 14 18 -24 59 33 -23 41 34 - 33 0 0 -24 25 6 22 55 56 36 270 -42 -24 31 23 -24 18 49 -25 4 2 -23 46 7 - 32 0 0 -24 29 6 22 55 59 35 270 -43 -24 35 23 -24 22 49 -25 8 0 -23 50 8 - 31 0 0 -24 32 36 22 56 2 34 269 -44 -24 38 52 -24 26 19 -25 11 29 -23 53 39 - 30 0 0 -24 35 35 22 56 4 33 269 -45 -24 41 51 -24 29 19 -25 14 27 -23 56 40 - 29 0 0 -24 38 4 22 56 7 32 268 -46 -24 44 20 -24 31 48 -25 16 55 -23 59 10 - 28 0 0 -24 40 3 22 56 9 31 268 -47 -24 46 19 -24 33 47 -25 18 53 -24 1 10 - 27 0 0 -24 41 32 22 56 11 30 268 -47 -24 47 48 -24 35 16 -25 20 21 -24 2 39 - 26 0 0 -24 42 30 22 56 14 29 267 -48 -24 48 46 -24 36 15 -25 21 20 -24 3 38 - 25 0 0 -24 42 59 22 56 16 28 267 -49 -24 49 15 -24 36 43 -25 21 48 -24 4 7 - 24 0 0 -24 42 57 22 56 18 28 266 -50 -24 49 13 -24 36 41 -25 21 46 -24 4 6 - 23 0 0 -24 42 26 22 56 20 27 266 -51 -24 48 42 -24 36 10 -25 21 15 -24 3 34 - 22 0 0 -24 41 24 22 56 22 26 266 -52 -24 47 40 -24 35 8 -25 20 13 -24 2 32 - 21 0 0 -24 39 52 22 56 24 25 265 -53 -24 46 8 -24 33 36 -25 18 42 -24 0 59 - 20 0 0 -24 37 51 22 56 26 24 265 -54 -24 44 7 -24 31 34 -25 16 41 -23 58 57 - 19 0 0 -24 35 19 22 56 28 23 264 -55 -24 41 35 -24 29 3 -25 14 11 -23 56 24 - 18 0 0 -24 32 17 22 56 30 22 264 -56 -24 38 34 -24 26 1 -25 11 10 -23 53 21 - 17 0 0 -24 28 46 22 56 31 21 264 -57 -24 35 2 -24 22 29 -25 7 40 -23 49 48 - 16 0 0 -24 24 44 22 56 33 20 263 -58 -24 31 1 -24 18 27 -25 3 39 -23 45 45 - 15 0 0 -24 20 12 22 56 34 19 263 -58 -24 26 29 -24 13 55 -24 59 9 -23 41 12 - 14 0 0 -24 15 10 22 56 36 18 262 -59 -24 21 28 -24 8 53 -24 54 10 -23 36 8 - 13 0 0 -24 9 39 22 56 37 17 262 -60 -24 15 56 -24 3 21 -24 48 40 -23 30 34 - 12 0 0 -24 3 37 22 56 39 16 262 -61 -24 9 55 -23 57 18 -24 42 40 -23 24 30 - 11 0 0 -23 57 5 22 56 40 16 261 -62 -24 3 23 -23 50 46 -24 36 11 -23 17 56 - 10 0 0 -23 50 3 22 56 41 15 261 -63 -23 56 22 -23 43 44 -24 29 12 -23 10 51 - 9 0 0 -23 42 31 22 56 42 14 260 -64 -23 48 50 -23 36 11 -24 21 42 -23 3 16 - 8 0 0 -23 34 29 22 56 43 13 260 -65 -23 40 49 -23 28 9 -24 13 43 -22 55 11 - 7 0 0 -23 25 56 22 56 44 12 260 -66 -23 32 17 -23 19 36 -24 5 14 -22 46 36 - 6 0 0 -23 16 54 22 56 45 11 259 -67 -23 23 15 -23 10 33 -23 56 15 -22 37 30 - 5 0 0 -23 7 21 22 56 46 10 259 -68 -23 13 43 -23 0 59 -23 46 46 -22 27 53 - 4 0 0 -22 57 18 22 56 47 9 259 -69 -23 3 40 -22 50 56 -23 36 46 -22 17 47 - 3 0 0 -22 46 45 22 56 48 8 258 -70 -22 53 8 -22 40 22 -23 26 17 -22 7 10 - 2 0 0 -22 35 42 22 56 48 7 258 -70 -22 42 5 -22 29 18 -23 15 18 -21 56 2 - 1 0 0 -22 24 8 22 56 49 6 257 -71 -22 30 32 -22 17 44 -23 3 48 -21 44 24 0 0 0 -22 12 4 22 56 49 5 257 -72 -22 18 28 -22 5 39 -22 51 48 -21 32 16 1 0 0 -21 59 29 22 56 50 4 257 -73 -22 5 55 -21 53 4 -22 39 18 -21 19 37 2 0 0 -21 46 24 22 56 50 3 256 -74 -21 52 51 -21 39 58 -22 26 18 -21 6 28 3 0 0 -21 32 49 22 56 50 2 256 -75 -21 39 16 -21 26 22 -22 12 48 -20 52 48 4 0 0 -21 18 44 22 56 50 1 256 -76 -21 25 12 -21 12 16 -21 58 47 -20 38 37 5 0 0 -21 4 8 22 56 50 0 255 -77 -21 10 37 -20 57 39 -21 44 16 -20 23 56 Uncertainty in time = +/- 3 secs Prediction of 2012 Jun 21.0 Data for the target star ------------------------ * name: TYC 5561-00665-1 * constellation : Virgo * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 14 15 38.7391 DE: -13 56 39.276 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .025, .023 ) * V mag [mag]: 10.0 * B mag [mag]: 11.3 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1388) Aphrodite approx. diameter [km]: 23 approx. diameter ["]: .011 distance from Earth [AU]: 2.96100 * orbital information: orbit source: Preston date of fit: 2012 Jun 21 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 992 number of rejected observations: 34 time covered by the observations: 1935 Sep 28 - 2012 May 21 1 sigma uncertainty ellipse (major, minor, PA): 0.027, 0.018, 122° remarks: * orbital elements for (1388) Aphrodite : Mean anomaly = 295.39924925 deg Arg. of pericenter = 256.47788674 deg Long. of node = 54.49629420 deg Inclination = 11.17946539 deg Eccentricity = 0.09377200 Semimajor axis = 3.01955857 AU Perihelion dist = 2.73640852 AU Mag: H = 10.82, G = 0.15 Epoch of elements : MJD 56149.95300000 TDT (2012 Aug 10.953) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Aug 10 1388 Aphrodite 22h 52.2m UT 10.0 14 15 38.739-13 56 39.28TYC 5561-00665-1 11.3 16.6 23 1.0 2.961 2.290 -17.49 -88.9460 -13.939 -161.73 15.22 22.8693 0.05430 0.09363 11.22135 -5.89051 0.00520 -0.00182 2000 293.5296742012 8 1.00000256.477887 54.496294 11.1794650.09377200 3.0195586 2.736408510.9 5.00.15 RATE 1.8784030 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.036 0.028 108 3.60 0.028 0 0 1 4 056099.0020120810_0665-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Jun 21, 00:53 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org