IOTA/IOTA-ES occultation update for (1) Ceres / TYC 1306-00077-1 event on 2012 Sep 07, 02:58 UT Visible from Africa Summary ------- On 2012 Sep 07 UT, the 960 km diameter asteroid (1) Ceres will occult a 11.8 mag star in the constellation Taurus for observers along a path across Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.1 mag to 8.8 mag (the magnitude of the asteroid) for at most 43.5 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: 100 * date and approx. time of event: 2012 Sep 07, 02:53 - 2012 Sep 07, 02:57 UT * geocentric midpoint of event [JD]: 2456177.623675 * magnitude of target star: 11.8 * magnitude drop [mag]: 0.1 * estimated maximum duration [s]: 43.5 * Moon: 63 % sunlit, 26° distance * Sun: 79° distance * rough path description: Africa Additional comments ------------------- extremely small mag drop The occultation path -------------------- * approximate projected width [km]: 962 * 1 sigma uncertainty interval [path widths]: +/- 0.04 * 1 sigma uncertainty interval [seconds]: +/- 1.8 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .021 +/- .020) * 1 sigma uncertainty ellipse (major, minor, PA): ( .021", .020", 88° ) * approx speed of asteroid's shadow [km/s]: 22.0814 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 1306-00077-1 by 1 Ceres on 2012 Sep 7 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 - 30 0 0 -10 1 23 2 53 19 1 69 -76 .. .. .. - 5 22 41 .. .. .. - 5 0 23 - 29 0 0 - 9 38 41 2 53 19 2 69 -75 -14 18 59 - 4 59 46 -14 41 31 - 4 37 28 - 28 0 0 - 9 15 49 2 53 19 3 69 -74 -13 56 19 - 4 36 43 -14 18 52 - 4 14 24 - 27 0 0 - 8 52 49 2 53 20 4 69 -73 -13 33 30 - 4 13 32 -13 56 4 - 3 51 12 - 26 0 0 - 8 29 41 2 53 20 5 68 -72 -13 10 32 - 3 50 14 -13 33 7 - 3 27 53 - 25 0 0 - 8 6 25 2 53 21 6 68 -71 -12 47 26 - 3 26 49 -13 10 2 - 3 4 27 - 24 0 0 - 7 43 3 2 53 21 7 68 -70 -12 24 13 - 3 3 17 -12 46 49 - 2 40 55 - 23 0 0 - 7 19 34 2 53 22 8 68 -69 -12 0 52 - 2 39 40 -12 23 29 - 2 17 17 - 22 0 0 - 6 55 59 2 53 23 9 68 -68 -11 37 24 - 2 15 58 -12 0 2 - 1 53 34 - 21 0 0 - 6 32 18 2 53 24 10 68 -67 -11 13 50 - 1 52 11 -11 36 29 - 1 29 47 - 20 0 0 - 6 8 33 2 53 25 12 68 -66 -10 50 11 - 1 28 20 -11 12 50 - 1 5 55 - 19 0 0 - 5 44 43 2 53 26 13 68 -65 -10 26 26 - 1 4 26 -10 49 6 - 0 42 1 - 18 0 0 - 5 20 50 2 53 27 14 67 -64 -10 2 37 - 0 40 28 -10 25 17 - 0 18 3 - 17 0 0 - 4 56 54 2 53 28 15 67 -63 - 9 38 44 - 0 16 29 -10 1 24 0 5 57 - 16 0 0 - 4 32 55 2 53 30 16 67 -62 - 9 14 48 0 7 33 - 9 37 28 0 29 58 - 15 0 0 - 4 8 54 2 53 31 17 67 -61 - 8 50 49 0 31 35 - 9 13 29 0 54 1 - 14 0 0 - 3 44 51 2 53 33 18 67 -60 - 8 26 47 0 55 38 - 8 49 28 1 18 4 - 13 0 0 - 3 20 48 2 53 35 19 67 -59 - 8 2 44 1 19 41 - 8 25 25 1 42 7 - 12 0 0 - 2 56 45 2 53 37 20 67 -58 - 7 38 40 1 43 44 - 8 1 20 2 6 9 - 11 0 0 - 2 32 42 2 53 38 21 67 -57 - 7 14 35 2 7 45 - 7 37 16 2 30 10 - 10 0 0 - 2 8 40 2 53 40 22 67 -56 - 6 50 31 2 31 44 - 7 13 11 2 54 10 - 9 0 0 - 1 44 39 2 53 43 23 67 -55 - 6 26 27 2 55 41 - 6 49 7 3 18 6 - 8 0 0 - 1 20 41 2 53 45 24 67 -54 - 6 2 24 3 19 35 - 6 25 4 3 42 0 - 7 0 0 - 0 56 45 2 53 47 26 67 -53 - 5 38 24 3 43 25 - 6 1 3 4 5 50 - 6 0 0 - 0 32 53 2 53 50 27 67 -52 - 5 14 26 4 7 12 - 5 37 4 4 29 35 - 5 0 0 - 0 9 5 2 53 52 28 67 -51 - 4 50 31 4 30 53 - 5 13 9 4 53 16 - 4 0 0 0 14 39 2 53 55 29 67 -50 - 4 26 40 4 54 29 - 4 49 17 5 16 52 - 3 0 0 0 38 17 2 53 57 30 67 -49 - 4 2 53 5 17 59 - 4 25 29 5 40 21 - 2 0 0 1 1 50 2 54 0 31 67 -47 - 3 39 11 5 41 23 - 4 1 47 6 3 44 - 1 0 0 1 25 17 2 54 3 32 67 -46 - 3 15 34 6 4 40 - 3 38 9 6 27 0 0 0 0 1 48 37 2 54 6 33 67 -45 - 2 52 4 6 27 49 - 3 14 38 6 50 8 1 0 0 2 11 49 2 54 9 34 67 -44 - 2 28 40 6 50 50 - 2 51 13 7 13 8 2 0 0 2 34 54 2 54 12 35 67 -43 - 2 5 23 7 13 42 - 2 27 56 7 36 0 3 0 0 2 57 50 2 54 15 36 67 -42 - 1 42 14 7 36 25 - 2 4 46 7 58 42 4 0 0 3 20 37 2 54 19 37 67 -41 - 1 19 14 7 58 58 - 1 41 44 8 21 14 5 0 0 3 43 14 2 54 22 39 67 -40 - 0 56 22 8 21 21 - 1 18 52 8 43 36 6 0 0 4 5 41 2 54 25 40 67 -39 - 0 33 40 8 43 34 - 0 56 8 9 5 47 7 0 0 4 27 58 2 54 29 41 67 -38 - 0 11 8 9 5 35 - 0 33 35 9 27 47 8 0 0 4 50 4 2 54 32 42 67 -37 0 11 13 9 27 24 - 0 11 12 9 49 35 9 0 0 5 11 58 2 54 36 43 67 -36 0 33 24 9 49 2 0 11 0 10 11 11 10 0 0 5 33 39 2 54 40 44 67 -35 0 55 23 10 10 26 0 33 0 10 32 34 11 0 0 5 55 9 2 54 44 45 67 -34 1 17 10 10 31 38 0 54 48 10 53 44 12 0 0 6 16 25 2 54 47 46 67 -33 1 38 44 10 52 36 1 16 24 11 14 41 13 0 0 6 37 27 2 54 51 47 67 -32 2 0 5 11 13 20 1 37 47 11 35 23 14 0 0 6 58 16 2 54 55 48 67 -30 2 21 13 11 33 49 1 58 56 11 55 51 15 0 0 7 18 50 2 54 59 49 67 -29 2 42 7 11 54 4 2 19 52 12 16 5 16 0 0 7 39 10 2 55 3 50 67 -28 3 2 47 12 14 4 2 40 33 12 36 3 17 0 0 7 59 14 2 55 8 51 67 -27 3 23 11 12 33 48 3 0 59 12 55 45 18 0 0 8 19 3 2 55 12 52 67 -26 3 43 20 12 53 16 3 21 10 13 15 12 19 0 0 8 38 36 2 55 16 53 67 -25 4 3 14 13 12 28 3 41 5 13 34 22 20 0 0 8 57 53 2 55 20 54 67 -24 4 22 52 13 31 24 4 0 45 13 53 16 21 0 0 9 16 52 2 55 25 56 67 -23 4 42 13 13 50 2 4 20 7 14 11 53 22 0 0 9 35 35 2 55 29 57 67 -22 5 1 17 14 8 24 4 39 13 14 30 12 23 0 0 9 54 1 2 55 34 58 67 -21 5 20 4 14 26 27 4 58 2 14 48 14 24 0 0 10 12 8 2 55 38 59 67 -20 5 38 34 14 44 13 5 16 33 15 5 59 25 0 0 10 29 58 2 55 43 60 67 -19 5 56 45 15 1 41 5 34 47 15 23 25 26 0 0 10 47 29 2 55 47 61 67 -18 6 14 39 15 18 51 5 52 42 15 40 32 27 0 0 11 4 42 2 55 52 62 67 -17 6 32 13 15 35 42 6 10 19 15 57 22 28 0 0 11 21 36 2 55 57 63 67 -16 6 49 29 15 52 14 6 27 36 16 13 52 29 0 0 11 38 11 2 56 1 64 67 -15 7 6 26 16 8 27 6 44 35 16 30 3 30 0 0 11 54 27 2 56 6 65 67 -14 7 23 4 16 24 20 7 1 14 16 45 55 31 0 0 12 10 22 2 56 11 66 67 -13 7 39 22 16 39 54 7 17 34 17 1 27 32 0 0 12 25 58 2 56 15 67 67 -12 7 55 19 16 55 9 7 33 33 17 16 40 33 0 0 12 41 14 2 56 20 68 67 -11 8 10 57 17 10 3 7 49 13 17 31 33 34 0 0 12 56 10 2 56 25 69 66 -10 8 26 14 17 24 38 8 4 32 17 46 5 35 0 0 13 10 46 2 56 30 70 66 -9 8 41 11 17 38 52 8 19 30 18 0 18 36 0 0 13 25 0 2 56 35 71 66 -8 8 55 47 17 52 45 8 34 8 18 14 10 37 0 0 13 38 54 2 56 40 72 65 -7 9 10 2 18 6 19 8 48 24 18 27 41 38 0 0 13 52 27 2 56 45 73 65 -6 9 23 55 18 19 31 9 2 19 18 40 52 39 0 0 14 5 39 2 56 49 74 64 -5 9 37 27 18 32 22 9 15 53 18 53 42 40 0 0 14 18 29 2 56 54 75 64 -4 9 50 38 18 44 53 9 29 5 19 6 11 41 0 0 14 30 58 2 56 59 76 63 -3 10 3 26 18 57 3 9 41 55 19 18 19 42 0 0 14 43 6 2 57 4 77 62 -2 10 15 53 19 8 51 9 54 24 19 30 5 43 0 0 14 54 51 2 57 9 78 61 -1 10 27 58 19 20 18 10 6 30 19 41 31 Uncertainty in time = +/- 2 secs Prediction of 2012 Jul 21.0 Data for the target star ------------------------ * name: TYC 1306-00077-1 * constellation : Taurus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 05 40 14.5513 DE: +20 23 15.305 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .019, .019 ) * V mag [mag]: 11.8 * B mag [mag]: 11.9 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1) Ceres approx. diameter [km]: 960 approx. diameter ["]: .481 distance from Earth [AU]: 2.74900 * orbital information: orbit source: Preston date of fit: 2012 Jul 21 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 5547 number of rejected observations: 643 time covered by the observations: 1900 Jul 15 - 2011 Dec 15 1 sigma uncertainty ellipse (major, minor, PA): 0.008, 0.006, 75° remarks: * orbital elements for (1) Ceres : Mean anomaly = 280.53494164 deg Arg. of pericenter = 71.87364143 deg Long. of node = 80.33111969 deg Inclination = 10.59266860 deg Eccentricity = 0.07700308 Semimajor axis = 2.77017300 AU Perihelion dist = 2.55686116 AU Mag: H = 3.38, G = 0.12 Epoch of elements : MJD 56177.12400000 TDT (2012 Sep 07.124) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 7 1 Ceres 2h 58.1m UT 11.8 5 40 14.551 20 23 15.31TYC 1306-00077-1 11.9 8.8 960 43.5 2.749 2.813 4.98 53.9392 20.386 134.98 5.95 2.9682 0.00296 -0.06617 12.36589 1.55547 -0.00553 -0.00024 2000 279.0120552012 831.00000 71.873641 80.331120 10.5926690.07700308 2.7701730 2.5568611 3.3 5.00.12 RATE 2.1376850 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.021 0.020 88 1.04 0.020 0 0 3-5 056129.0020120907_0077-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Jul 21, 15:15 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org