IOTA/IOTA-ES occultation update for (322) Phaeo / 2UCAC 39469714 event on 2012 Oct 02, 09:16 UT Visible from SE USA, Mexico Summary ------- On 2012 Oct 02 UT, the 72 km diameter asteroid (322) Phaeo will occult a 12.5 mag star in the constellation Gemini for observers along a path across SE USA, Mexico. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.6 mag to 13.8 mag (the magnitude of the asteroid) for at most 4.1 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Hugh Harris, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 77 * date and approx. time of event: 2012 Oct 02, 09:10 - 2012 Oct 02, 09:16 UT * geocentric midpoint of event [JD]: 2456202.88656667 * magnitude of target star: 12.5 * magnitude drop [mag]: 1.6 * estimated maximum duration [s]: 4.1 * Moon: 95 % sunlit, 67° distance * Sun: 87° distance * rough path description: SE USA, Mexico The occultation path -------------------- * approximate projected width [km]: 72 * 1 sigma uncertainty interval [path widths]: +/- 0.72 * 1 sigma uncertainty interval [seconds]: +/- 2.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .028 +/- .032) * 1 sigma uncertainty ellipse (major, minor, PA): ( .032", .028", 1° ) * approx speed of asteroid's shadow [km/s]: 17.6233 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 39469714 by 322 Phaeo on 2012 Oct 2 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 -142 0 0 16 31 23 9 10 38 0 67 -77 16 10 10 16 52 36 .. .. .. 17 23 10 -141 0 0 16 55 40 9 10 38 1 67 -77 16 34 29 17 16 50 16 4 0 17 47 21 -140 0 0 17 19 36 9 10 38 2 68 -77 16 58 28 17 40 45 16 28 3 18 11 12 -139 0 0 17 43 12 9 10 39 3 68 -76 17 22 6 18 4 18 16 51 44 18 34 42 -138 0 0 18 6 27 9 10 39 4 68 -76 17 45 24 18 27 31 17 15 5 18 57 52 -137 0 0 18 29 21 9 10 40 5 69 -75 18 8 20 18 50 22 17 38 5 19 20 39 -136 0 0 18 51 53 9 10 40 6 69 -74 18 30 54 19 12 52 18 0 43 19 43 6 -135 0 0 19 14 3 9 10 41 7 69 -74 18 53 7 19 35 0 18 22 58 20 5 10 -134 0 0 19 35 51 9 10 42 8 70 -73 19 14 57 19 56 45 18 44 52 20 26 51 -133 0 0 19 57 16 9 10 43 9 70 -72 19 36 24 20 18 7 19 6 23 20 48 10 -132 0 0 20 18 18 9 10 44 10 70 -72 19 57 29 20 39 7 19 27 31 21 9 6 -131 0 0 20 38 57 9 10 45 11 71 -71 20 18 11 20 59 43 19 48 16 21 29 39 -130 0 0 20 59 12 9 10 47 12 71 -70 20 38 29 21 19 57 20 8 38 21 49 49 -129 0 0 21 19 4 9 10 48 13 71 -69 20 58 23 21 39 46 20 28 36 22 9 35 -128 0 0 21 38 33 9 10 50 14 72 -69 21 17 54 21 59 12 20 48 10 22 28 57 -127 0 0 21 57 37 9 10 51 15 72 -68 21 37 0 22 18 13 21 7 20 22 47 55 -126 0 0 22 16 17 9 10 53 16 72 -67 21 55 43 22 36 51 21 26 6 23 6 29 -125 0 0 22 34 32 9 10 55 17 73 -66 22 14 1 22 55 4 21 44 28 23 24 38 -124 0 0 22 52 23 9 10 57 18 73 -65 22 31 54 23 12 52 22 2 25 23 42 23 -123 0 0 23 9 49 9 10 59 19 74 -64 22 49 23 23 30 16 22 19 57 23 59 44 -122 0 0 23 26 51 9 11 1 20 74 -64 23 6 27 23 47 15 22 37 4 24 16 39 -121 0 0 23 43 28 9 11 3 21 74 -63 23 23 6 24 3 50 22 53 47 24 33 10 -120 0 0 23 59 39 9 11 5 22 75 -62 23 39 20 24 19 59 23 10 4 24 49 16 -119 0 0 24 15 26 9 11 7 23 75 -61 23 55 8 24 35 43 23 25 56 25 4 57 -118 0 0 24 30 47 9 11 10 24 76 -60 24 10 32 24 51 2 23 41 23 25 20 12 -117 0 0 24 45 43 9 11 12 25 76 -59 24 25 30 25 5 56 23 56 24 25 35 3 -116 0 0 25 0 13 9 11 15 26 77 -58 24 40 3 25 20 24 24 11 0 25 49 28 -115 0 0 25 14 18 9 11 18 27 77 -57 24 54 10 25 34 27 24 25 10 26 3 28 -114 0 0 25 27 58 9 11 20 28 77 -57 25 7 52 25 48 4 24 38 55 26 17 2 -113 0 0 25 41 12 9 11 23 29 78 -56 25 21 8 26 1 16 24 52 14 26 30 11 -112 0 0 25 54 0 9 11 26 30 78 -55 25 33 58 26 14 2 25 5 8 26 42 54 -111 0 0 26 6 23 9 11 29 31 79 -54 25 46 23 26 26 23 25 17 35 26 55 12 -110 0 0 26 18 20 9 11 32 32 79 -53 25 58 22 26 38 19 25 29 37 27 7 5 -109 0 0 26 29 52 9 11 35 33 80 -52 26 9 56 26 49 48 25 41 13 27 18 32 -108 0 0 26 40 58 9 11 39 34 80 -51 26 21 3 27 0 52 25 52 24 27 29 33 -107 0 0 26 51 38 9 11 42 34 81 -51 26 31 45 27 11 30 26 3 8 27 40 9 -106 0 0 27 1 52 9 11 45 35 81 -50 26 42 1 27 21 43 26 13 27 27 50 19 -105 0 0 27 11 41 9 11 49 36 82 -49 26 51 51 27 31 30 26 23 19 28 0 3 -104 0 0 27 21 3 9 11 52 37 82 -48 27 1 16 27 40 51 26 32 46 28 9 22 -103 0 0 27 30 1 9 11 56 38 83 -47 27 10 15 27 49 47 26 41 47 28 18 16 -102 0 0 27 38 32 9 11 59 39 83 -46 27 18 47 27 58 17 26 50 22 28 26 43 -101 0 0 27 46 38 9 12 3 40 84 -45 27 26 54 28 6 21 26 58 31 28 34 46 -100 0 0 27 54 18 9 12 7 41 84 -44 27 34 36 28 14 0 27 6 14 28 42 22 - 99 0 0 28 1 32 9 12 10 42 85 -44 27 41 51 28 21 12 27 13 31 28 49 33 - 98 0 0 28 8 20 9 12 14 43 85 -43 27 48 41 28 28 0 27 20 23 28 56 19 - 97 0 0 28 14 43 9 12 18 44 86 -42 27 55 5 28 34 21 27 26 48 29 2 39 - 96 0 0 28 20 40 9 12 22 44 86 -41 28 1 3 28 40 17 27 32 48 29 8 33 - 95 0 0 28 26 11 9 12 26 45 87 -40 28 6 35 28 45 47 27 38 21 29 14 2 - 94 0 0 28 31 16 9 12 30 46 87 -39 28 11 41 28 50 52 27 43 29 29 19 5 - 93 0 0 28 35 56 9 12 34 47 88 -38 28 16 22 28 55 31 27 48 11 29 23 43 - 92 0 0 28 40 10 9 12 38 48 88 -37 28 20 36 28 59 44 27 52 27 29 27 55 - 91 0 0 28 43 58 9 12 43 49 89 -37 28 24 25 29 3 31 27 56 17 29 31 41 - 90 0 0 28 47 21 9 12 47 50 89 -36 28 27 49 29 6 53 27 59 41 29 35 2 - 89 0 0 28 50 18 9 12 51 51 90 -35 28 30 46 29 9 50 28 2 39 29 37 58 - 88 0 0 28 52 49 9 12 56 52 90 -34 28 33 17 29 12 20 28 5 11 29 40 28 - 87 0 0 28 54 54 9 13 0 53 91 -33 28 35 23 29 14 25 28 7 17 29 42 32 - 86 0 0 28 56 34 9 13 5 53 91 -32 28 37 3 29 16 5 28 8 58 29 44 11 - 85 0 0 28 57 48 9 13 9 54 92 -31 28 38 17 29 17 18 28 10 12 29 45 24 - 84 0 0 28 58 36 9 13 14 55 92 -31 28 39 5 29 18 6 28 11 1 29 46 12 - 83 0 0 28 58 58 9 13 19 56 93 -30 28 39 28 29 18 28 28 11 23 29 46 34 - 82 0 0 28 58 54 9 13 23 57 94 -29 28 39 24 29 18 25 28 11 20 29 46 31 - 81 0 0 28 58 25 9 13 28 58 94 -28 28 38 55 29 17 56 28 10 50 29 46 2 - 80 0 0 28 57 30 9 13 33 59 95 -27 28 38 0 29 17 1 28 9 55 29 45 7 - 79 0 0 28 56 9 9 13 38 60 95 -26 28 36 38 29 15 40 28 8 33 29 43 47 - 78 0 0 28 54 22 9 13 43 61 96 -25 28 34 51 29 13 54 28 6 45 29 42 1 - 77 0 0 28 52 10 9 13 48 61 97 -24 28 32 38 29 11 41 28 4 32 29 39 49 - 76 0 0 28 49 31 9 13 53 62 97 -24 28 29 59 29 9 3 28 1 52 29 37 11 - 75 0 0 28 46 26 9 13 58 63 98 -23 28 26 54 29 5 59 27 58 46 29 34 8 - 74 0 0 28 42 56 9 14 3 64 98 -22 28 23 23 29 2 29 27 55 14 29 30 39 - 73 0 0 28 38 59 9 14 8 65 99 -21 28 19 26 28 58 33 27 51 16 29 26 44 - 72 0 0 28 34 37 9 14 13 66 100 -20 28 15 2 28 54 12 27 46 51 29 22 24 - 71 0 0 28 29 48 9 14 18 67 100 -19 28 10 13 28 49 24 27 42 0 29 17 37 - 70 0 0 28 24 34 9 14 23 68 101 -18 28 4 57 28 44 10 27 36 43 29 12 25 - 69 0 0 28 18 53 9 14 29 69 102 -17 27 59 15 28 38 30 27 31 0 29 6 47 - 68 0 0 28 12 46 9 14 34 69 102 -16 27 53 7 28 32 24 27 24 50 29 0 42 - 67 0 0 28 6 12 9 14 40 70 103 -16 27 46 33 28 25 52 27 18 14 28 54 12 - 66 0 0 27 59 13 9 14 45 71 104 -15 27 39 32 28 18 54 27 11 12 28 47 15 - 65 0 0 27 51 47 9 14 50 72 105 -14 27 32 5 28 11 30 27 3 43 28 39 53 - 64 0 0 27 43 55 9 14 56 73 106 -13 27 24 11 28 3 39 26 55 47 28 32 4 - 63 0 0 27 35 37 9 15 2 74 106 -12 27 15 51 27 55 22 26 47 25 28 23 49 - 62 0 0 27 26 52 9 15 7 75 107 -11 27 7 5 27 46 39 26 38 37 28 15 8 - 61 0 0 27 17 41 9 15 13 76 108 -10 26 57 52 27 37 29 26 29 21 28 6 1 - 60 0 0 27 8 3 9 15 18 77 109 -9 26 48 13 27 27 53 26 19 40 27 56 27 - 59 0 0 26 57 59 9 15 24 78 111 -8 26 38 7 27 17 51 26 9 31 27 46 27 - 58 0 0 26 47 28 9 15 30 78 112 -7 26 27 34 27 7 22 25 58 56 27 36 1 - 57 0 0 26 36 31 9 15 36 79 113 -7 26 16 35 26 56 26 25 47 54 27 25 8 - 56 0 0 26 25 7 9 15 42 80 115 -6 26 5 10 26 45 4 25 36 26 27 13 49 - 55 0 0 26 13 17 9 15 47 81 117 -5 25 53 17 26 33 16 25 24 31 27 2 4 - 54 0 0 26 1 0 9 15 53 82 119 -4 25 40 58 26 21 1 25 12 9 26 49 52 - 53 0 0 25 48 16 9 15 59 83 122 -3 25 28 13 26 8 20 24 59 20 26 37 13 - 52 0 0 25 35 6 9 16 5 84 125 -2 25 15 0 25 55 12 24 46 4 26 24 9 - 51 0 0 25 21 29 9 16 11 85 130 -1 25 1 21 25 41 37 24 32 22 26 10 37 - 50 0 0 25 7 26 9 16 17 85 136 0 24 47 16 25 27 36 24 18 13 25 56 39 Uncertainty in time = +/- 3 secs Prediction of 2012 Aug 6.0 Data for the target star ------------------------ * name: 2UCAC 39469714 * constellation : Gemini * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 06 53 58.3511 DE: +21 59 53.384 * position source: mpos:UCAC4 pm:UCAC4 * standard error: RA,DE ["]: ( .022, .030 ) * V mag [mag]: 12.5 * B mag [mag]: 0.0 * Apparent position with proper motion RA(deg): 103.6882585586 DE(deg): 21.9800777519 * Equation of equinoxes (radians) : 0.000062589864584 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (322) Phaeo approx. diameter [km]: 72 approx. diameter ["]: .044 distance from Earth [AU]: 2.25200 * orbital information: orbit source: Preston date of fit: 2012 Jul 09 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 961 number of rejected observations: 74 time covered by the observations: 1900 Sep 25 - 2011 Oct 28 1 sigma uncertainty ellipse (major, minor, PA): 0.018, 0.009, 104° remarks: * orbital elements for (322) Phaeo : Mean anomaly = 45.48449020 deg Arg. of pericenter = 115.50076119 deg Long. of node = 252.37950143 deg Inclination = 8.05435253 deg Eccentricity = 0.24600429 Semimajor axis = 2.78375933 AU Perihelion dist = 2.09894259 AU Mag: H = 8.99, G = 0.15 Epoch of elements : MJD 56202.38700000 TDT (2012 Oct 02.387) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Oct 2 322 Phaeo 9h 16.7m UT 12.5 6 53 58.351 21 59 53.382UCAC 39469714 0.0 13.8 72 4.1 2.252 2.691 -10.37 -47.1687 22.001 38.15 -3.80 9.2776 0.00961 0.03643 9.58638 -2.65445 -0.00553 0.00051 2000 44.9779562012 930.00000115.500761252.379501 8.0543530.24600429 2.7837593 2.0989426 9.0 5.00.15 RATE 2.1220540 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.032 0.028 1 1.72 0.031 0 0 1 4 056145.0020121002_469714 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Aug 06, 17:07 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org