IOTA/IOTA-ES occultation update for (363) Padua / HIP 72622 event on 2012 Sep 16, 20:09 UT Visible from W Africa, USA (daylight) Summary ------- On 2012 Sep 16 UT, the 91 km diameter asteroid (363) Padua will occult a 2.7 mag star in the constellation Libra for observers along a path across W Africa, USA (daylight). In the case of an occultation, the combined light of the asteroid and the star will drop by 12.1 mag to 14.8 mag (the magnitude of the asteroid) for at most 2.6 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Hugh Harris, 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: . The event at a glimpse ---------------------- * Rank: 99 * date and approx. time of event: 2012 Sep 16, 20:10 - 2012 Sep 16, 20:11 UT * geocentric midpoint of event [JD]: 2456187.33986667 * magnitude of target star: 2.7 * magnitude drop [mag]: 12.1 * estimated maximum duration [s]: 2.6 * Moon: 1 % sunlit, 41° distance * Sun: 51° distance * rough path description: W Africa, USA (daylight) Additional comments ------------------- wide double star The occultation path -------------------- * approximate projected width [km]: 118 * 1 sigma uncertainty interval [path widths]: +/- 0.20 * 1 sigma uncertainty interval [seconds]: +/- 0.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .013 +/- .008) * 1 sigma uncertainty ellipse (major, minor, PA): ( .014", .007", 111° ) * approx speed of asteroid's shadow [km/s]: 35.4586 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of HIP 72622 by 363 Padua on 2012 Sep 16 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 - 33 0 0 12 53 42 20 10 51 39 237 -1 12 21 40 13 25 58 12 9 34 13 38 17 - 32 0 0 12 48 25 20 10 54 38 238 -2 12 16 25 13 20 39 12 4 19 13 32 58 - 31 0 0 12 43 43 20 10 56 37 238 -3 12 11 44 13 15 55 11 59 39 13 28 13 - 30 0 0 12 39 35 20 10 59 36 239 -4 12 7 37 13 11 46 11 55 33 13 24 3 - 29 0 0 12 36 1 20 11 1 35 240 -4 12 4 5 13 8 11 11 52 0 13 20 28 - 28 0 0 12 33 1 20 11 3 35 240 -5 12 1 6 13 5 10 11 49 2 13 17 27 - 27 0 0 12 30 36 20 11 5 34 241 -6 11 58 42 13 2 44 11 46 38 13 15 0 - 26 0 0 12 28 45 20 11 7 33 241 -7 11 56 52 13 0 52 11 44 48 13 13 8 - 25 0 0 12 27 29 20 11 10 32 242 -8 11 55 36 12 59 35 11 43 32 13 11 51 - 24 0 0 12 26 47 20 11 12 31 242 -9 11 54 54 12 58 53 11 42 51 13 11 9 - 23 0 0 12 26 39 20 11 14 30 243 -10 11 54 46 12 58 45 11 42 43 13 11 1 - 22 0 0 12 27 5 20 11 16 29 243 -11 11 55 13 12 59 11 11 43 10 13 11 27 - 21 0 0 12 28 6 20 11 17 29 244 -12 11 56 13 13 0 12 11 44 10 13 12 28 - 20 0 0 12 29 41 20 11 19 28 244 -13 11 57 48 13 1 48 11 45 44 13 14 4 - 19 0 0 12 31 50 20 11 21 27 245 -14 11 59 56 13 3 57 11 47 53 13 16 13 - 18 0 0 12 34 33 20 11 23 26 245 -15 12 2 39 13 6 41 11 50 35 13 18 58 - 17 0 0 12 37 51 20 11 25 25 245 -16 12 5 55 13 10 0 11 53 51 13 22 16 - 16 0 0 12 41 42 20 11 26 24 246 -17 12 9 46 13 13 52 11 57 41 13 26 9 - 15 0 0 12 46 8 20 11 28 23 246 -18 12 14 10 13 18 19 12 2 5 13 30 37 - 14 0 0 12 51 7 20 11 29 22 246 -19 12 19 8 13 23 20 12 7 3 13 35 38 - 13 0 0 12 56 40 20 11 31 21 247 -20 12 24 40 13 28 55 12 12 34 13 41 14 - 12 0 0 13 2 47 20 11 32 20 247 -21 12 30 45 13 35 4 12 18 38 13 47 23 - 11 0 0 13 9 28 20 11 33 19 247 -22 12 37 24 13 41 46 12 25 16 13 54 7 - 10 0 0 13 16 42 20 11 35 18 248 -23 12 44 36 13 49 3 12 32 28 14 1 24 - 9 0 0 13 24 30 20 11 36 17 248 -24 12 52 22 13 56 53 12 40 13 14 9 15 - 8 0 0 13 32 52 20 11 37 16 248 -25 13 0 41 14 5 17 12 48 31 14 17 40 - 7 0 0 13 41 46 20 11 38 15 249 -26 13 9 33 14 14 14 12 57 22 14 26 38 - 6 0 0 13 51 14 20 11 39 14 249 -27 13 18 58 14 23 44 13 6 46 14 36 9 - 5 0 0 14 1 15 20 11 40 14 249 -28 13 28 56 14 33 48 13 16 43 14 46 14 - 4 0 0 14 11 48 20 11 41 13 250 -29 13 39 26 14 44 25 13 27 12 14 56 52 - 3 0 0 14 22 55 20 11 42 12 250 -30 13 50 30 14 55 35 13 38 14 15 8 3 - 2 0 0 14 34 34 20 11 42 11 250 -30 14 2 5 15 7 17 13 49 49 15 19 47 - 1 0 0 14 46 46 20 11 43 10 250 -31 14 14 14 15 19 33 14 1 55 15 32 4 0 0 0 14 59 30 20 11 44 9 251 -32 14 26 54 15 32 20 14 14 34 15 44 53 1 0 0 15 12 45 20 11 44 8 251 -33 14 40 6 15 45 40 14 27 45 15 58 14 2 0 0 15 26 33 20 11 45 7 251 -34 14 53 50 15 59 32 14 41 27 16 12 8 3 0 0 15 40 53 20 11 45 6 252 -35 15 8 5 16 13 55 14 55 41 16 26 33 4 0 0 15 55 44 20 11 46 5 252 -36 15 22 52 16 28 51 15 10 26 16 41 30 5 0 0 16 11 6 20 11 46 4 252 -37 15 38 10 16 44 17 15 25 43 16 56 58 6 0 0 16 26 59 20 11 46 3 252 -38 15 53 58 17 0 15 15 41 30 17 12 58 7 0 0 16 43 23 20 11 46 2 253 -38 16 10 18 17 16 44 15 57 47 17 29 28 8 0 0 17 0 17 20 11 46 1 253 -39 16 27 7 17 33 43 16 14 35 17 46 30 Uncertainty in time = +/- 1 secs Prediction of 2012 Jul 21.0 Data for the target star ------------------------ * name: HIP 72622 * alternate name: Alpha 2 Libra * constellation : Libra * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 14 50 52.6177 DE: -16 02 31.255 * position source: mpos:HIP2 pm:HIP2 plx:HIP2 * standard error: RA,DE ["]: ( .004, .003 ) * V mag [mag]: 2.7 * B mag [mag]: 2.9 * Apparent position with proper motion RA(deg): 222.8966961067 DE(deg): -16.0932954933 * Equation of equinoxes (radians) : 0.000066550918775 * Diameter [mas]: 1 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (363) Padua approx. diameter [km]: 91 approx. diameter ["]: .037 distance from Earth [AU]: 3.35100 * orbital information: orbit source: Preston date of fit: 2012 Jul 21 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 989 number of rejected observations: 120 time covered by the observations: 1916 Mar 10 - 2012 Jun 03 1 sigma uncertainty ellipse (major, minor, PA): 0.013, 0.007, 113° remarks: * orbital elements for (363) Padua : Mean anomaly = 249.77853976 deg Arg. of pericenter = 293.76666102 deg Long. of node = 64.89744523 deg Inclination = 5.94443546 deg Eccentricity = 0.07071933 Semimajor axis = 2.74821772 AU Perihelion dist = 2.55386561 AU Mag: H = 8.95, G = 0.15 Epoch of elements : MJD 56186.84000000 TDT (2012 Sep 16.840) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 16 363 Padua 20h 9.4m UT 2.7 14 50 52.618-16 2 31.26HIP 72622 2.9 14.8 93 2.6 3.351 3.422 -18.02 -75.8077 -16.037 -123.71 2.24 20.1568 0.21081 0.57658 18.79836 -6.86841 0.00426 -0.00128 2000 248.2988072012 910.00000293.766661 64.897445 5.9444350.07071933 2.7482177 2.5538656 9.0 5.00.15 RATE 2.1633530 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.014 0.007 111 1.19 0.007 0 1-3 5 456129.0020120916__72622 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Jul 22, 03:58 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org