IOTA/IOTA-ES occultation update for (892) Seeligeria / TYC 5754-01662-1 event on 2012 Dec 20, 16:01 UT Visible from Africa Summary ------- On 2012 Dec 20 UT, the 80 km diameter asteroid (892) Seeligeria will occult a 8.8 mag star in the constellation Aquila 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 7.2 mag to 16.0 mag (the magnitude of the asteroid) for at most 2.1 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: UCAC. The event at a glimpse ---------------------- * Rank: 62 * date and approx. time of event: 2012 Dec 20, 16:03 - 2012 Dec 20, 16:04 UT * geocentric midpoint of event [JD]: 2456282.1677125 * magnitude of target star: 8.8 * magnitude drop [mag]: 7.2 * estimated maximum duration [s]: 2.1 * Moon: 55 % sunlit, 57° distance * Sun: 40° distance * rough path description: Africa The occultation path -------------------- * approximate projected width [km]: 81 * 1 sigma uncertainty interval [path widths]: +/- 0.99 * 1 sigma uncertainty interval [seconds]: +/- 1.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .025 +/- .026) * 1 sigma uncertainty ellipse (major, minor, PA): ( .026", .025", 0° ) * approx speed of asteroid's shadow [km/s]: 38.8300 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5754-01662-1 by 892 Seeligeria on 2012 Dec 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 26 0 0 7 10 53 16 3 35 39 254 0 6 48 40 7 33 7 6 4 47 8 17 12 27 0 0 7 19 5 16 3 37 38 255 -1 6 56 52 7 41 19 6 12 58 8 25 24 28 0 0 7 27 20 16 3 39 37 255 -2 7 5 7 7 49 34 6 21 13 8 33 40 29 0 0 7 35 37 16 3 41 36 255 -3 7 13 24 7 57 51 6 29 30 8 41 57 30 0 0 7 43 56 16 3 42 35 255 -4 7 21 44 8 6 11 6 37 49 8 50 17 31 0 0 7 52 18 16 3 44 34 256 -5 7 30 5 8 14 32 6 46 10 8 58 39 32 0 0 8 0 42 16 3 45 33 256 -6 7 38 29 8 22 56 6 54 33 9 7 3 33 0 0 8 9 7 16 3 47 32 256 -7 7 46 54 8 31 22 7 2 59 9 15 29 34 0 0 8 17 34 16 3 49 31 256 -8 7 55 21 8 39 49 7 11 25 9 23 56 35 0 0 8 26 3 16 3 50 30 256 -9 8 3 50 8 48 17 7 19 54 9 32 25 36 0 0 8 34 33 16 3 51 29 257 -10 8 12 19 8 56 47 7 28 23 9 40 55 37 0 0 8 43 4 16 3 53 28 257 -11 8 20 50 9 5 18 7 36 54 9 49 26 38 0 0 8 51 36 16 3 54 27 257 -12 8 29 22 9 13 50 7 45 26 9 57 58 39 0 0 9 0 8 16 3 56 26 257 -13 8 37 55 9 22 23 7 53 59 10 6 31 40 0 0 9 8 42 16 3 57 25 257 -14 8 46 28 9 30 57 8 2 32 10 15 4 41 0 0 9 17 16 16 3 58 24 258 -15 8 55 2 9 39 31 8 11 6 10 23 38 42 0 0 9 25 50 16 3 59 23 258 -16 9 3 36 9 48 5 8 19 40 10 32 13 43 0 0 9 34 24 16 4 0 22 258 -17 9 12 11 9 56 39 8 28 14 10 40 47 44 0 0 9 42 59 16 4 1 21 258 -18 9 20 45 10 5 13 8 36 49 10 49 21 45 0 0 9 51 33 16 4 2 20 258 -19 9 29 19 10 13 48 8 45 23 10 57 55 46 0 0 10 0 6 16 4 3 19 258 -20 9 37 53 10 22 21 8 53 57 11 6 29 47 0 0 10 8 40 16 4 4 18 259 -21 9 46 26 10 30 55 9 2 30 11 15 2 48 0 0 10 17 12 16 4 5 17 259 -22 9 54 59 10 39 27 9 11 3 11 23 35 49 0 0 10 25 44 16 4 6 16 259 -23 10 3 31 10 47 59 9 19 35 11 32 6 50 0 0 10 34 15 16 4 7 15 259 -24 10 12 1 10 56 29 9 28 6 11 40 37 51 0 0 10 42 44 16 4 7 14 259 -25 10 20 31 11 4 59 9 36 35 11 49 6 52 0 0 10 51 12 16 4 8 13 260 -26 10 28 59 11 13 27 9 45 4 11 57 34 53 0 0 10 59 39 16 4 9 12 260 -27 10 37 26 11 21 54 9 53 31 12 6 1 54 0 0 11 8 4 16 4 9 11 260 -28 10 45 51 11 30 19 10 1 56 12 14 26 55 0 0 11 16 28 16 4 10 10 260 -29 10 54 15 11 38 42 10 10 20 12 22 49 56 0 0 11 24 49 16 4 10 9 260 -30 11 2 36 11 47 3 10 18 41 12 31 10 57 0 0 11 33 8 16 4 11 8 261 -31 11 10 55 11 55 22 10 27 1 12 39 28 58 0 0 11 41 25 16 4 11 7 261 -32 11 19 13 12 3 39 10 35 18 12 47 45 59 0 0 11 49 40 16 4 11 6 261 -33 11 27 27 12 11 54 10 43 33 12 55 59 60 0 0 11 57 52 16 4 12 5 261 -34 11 35 39 12 20 5 10 51 45 13 4 11 61 0 0 12 6 1 16 4 12 4 261 -34 11 43 49 12 28 14 10 59 55 13 12 20 62 0 0 12 14 7 16 4 12 3 262 -35 11 51 55 12 36 21 11 8 2 13 20 25 63 0 0 12 22 10 16 4 12 2 262 -36 11 59 59 12 44 24 11 16 5 13 28 28 64 0 0 12 30 11 16 4 12 1 262 -37 12 7 59 12 52 24 11 24 6 13 36 28 65 0 0 12 38 7 16 4 12 0 262 -38 12 15 56 13 0 20 11 32 3 .. .. .. Uncertainty in time = +/- 2 secs Prediction of 2012 Dec 17.0 Data for the target star ------------------------ * name: TYC 5754-01662-1 * constellation : Aquila * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 20 29 03.1954 DE: -07 30 38.259 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .022, .024 ) * V mag [mag]: 8.8 * B mag [mag]: 10.3 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (892) Seeligeria approx. diameter [km]: 80 approx. diameter ["]: .026 distance from Earth [AU]: 4.18600 * orbital information: orbit source: Preston date of fit: 2012 Oct 26 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 1011 number of rejected observations: 65 time covered by the observations: 1918 May 31 - 2012 Sep 30 1 sigma uncertainty ellipse (major, minor, PA): 0.012, 0.009, 93° remarks: * orbital elements for (892) Seeligeria : Mean anomaly = 219.43826150 deg Arg. of pericenter = 287.46493033 deg Long. of node = 175.95707782 deg Inclination = 21.31475191 deg Eccentricity = 0.10082400 Semimajor axis = 3.22843427 AU Perihelion dist = 2.90293062 AU Mag: H = 9.51, G = 0.15 Epoch of elements : MJD 56281.66800000 TDT (2012 Dec 20.668) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Dec 20 892 Seeligeria 16h 1.5m UT 8.8 20 29 3.195- 7 30 38.26TYC 5754-01662-1 10.3 16.0 80 2.1 4.186 3.092 2.41 -22.7541 -7.511 -60.90 -23.43 16.0251 -0.00878 0.16780 21.88677 1.14577 0.00344 0.00182 2000 219.15485320121219.00000287.464930175.957078 21.3147520.10082400 3.2284343 2.9029306 9.5 5.00.15 RATE 1.6990890 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.026 0.025 0 1.99 0.026 0 0 4 1 056278.0020121220_1662-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Oct 25, 23:56 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org