IOTA/IOTA-ES occultation update for (599) Luisa / 2UCAC 12080826 event on 2008 Jul 11, 03:15 UT Visible from USA Summary ------- On 2008 Jul 11 UT, the 65 km diameter asteroid (599) Luisa will occult a 12.6 mag star in the constellation Ara for observers along a path across USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.4 mag to 11.8 mag (the magnitude of the asteroid) for at most 9.0 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: 88 * date and approx. time of event: 2008 Jul 11, 03:14 - 2008 Jul 11, 03:17 UT * magnitude of target star: 12.6 * magnitude drop [mag]: 0.4 * estimated maximum duration [s]: 9.0 * Moon: 59 % sunlit, 57° distance * Sun: 147° distance * rough path description: USA Additional comments ------------------- very low altitude The occultation path -------------------- * approximate projected width [km]: 481 * 1 sigma uncertainty interval [path widths]: +/- 0.55 * 1 sigma uncertainty interval [seconds]: +/- 4.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .050 +/- .038) * 1 sigma uncertainty ellipse (major, minor, PA): ( .050", .037", 102° ) * approx speed of asteroid's shadow [km/s]: 7.2219 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 12080826 by 599 Luisa on 2008 Jul 11 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 - 96 0 0 40 23 34 3 17 32 1 166 -13 .. .. .. 36 46 7 .. .. .. 34 20 37 - 95 0 0 39 5 38 3 17 25 3 166 -15 .. .. .. 36 4 38 .. .. .. 33 48 57 - 94 0 0 38 11 51 3 17 17 4 167 -16 .. .. .. 35 30 33 .. .. .. 33 22 5 - 93 0 0 37 31 14 3 17 8 5 168 -17 .. .. .. 35 2 32 .. .. .. 32 59 30 - 92 0 0 36 59 48 3 16 58 5 168 -18 41 18 41 34 39 43 .. .. .. 32 40 48 - 91 0 0 36 35 32 3 16 47 6 169 -19 40 14 40 34 21 31 .. .. .. 32 25 43 - 90 0 0 36 17 18 3 16 37 6 170 -19 39 37 11 34 7 34 .. .. .. 32 14 4 - 89 0 0 36 4 25 3 16 25 7 170 -20 39 13 22 33 57 34 .. .. .. 32 5 41 - 88 0 0 35 56 27 3 16 14 7 171 -21 38 59 22 33 51 22 .. .. .. 32 0 28 - 87 0 0 35 53 10 3 16 2 7 172 -21 38 53 38 33 48 50 .. .. .. 31 58 22 - 86 0 0 35 54 27 3 15 51 7 172 -22 38 55 35 33 49 55 .. .. .. 31 59 21 - 85 0 0 36 0 22 3 15 39 7 173 -22 39 5 24 33 54 40 .. .. .. 32 3 25 - 84 0 0 36 11 1 3 15 27 7 174 -22 39 23 58 34 3 6 .. .. .. 32 10 37 - 83 0 0 36 26 44 3 15 14 7 174 -23 39 53 34 34 15 23 .. .. .. 32 21 1 - 82 0 0 36 48 3 3 15 2 7 175 -23 40 40 13 34 31 43 .. .. .. 32 34 44 - 81 0 0 37 15 47 3 14 50 6 176 -23 42 17 7 34 52 25 .. .. .. 32 51 56 - 80 0 0 37 51 21 3 14 38 6 176 -23 .. .. .. 35 17 56 .. .. .. 33 12 50 - 79 0 0 38 37 23 3 14 25 5 177 -23 .. .. .. 35 48 57 .. .. .. 33 37 45 - 78 0 0 39 39 41 3 14 13 4 178 -22 .. .. .. 36 26 28 .. .. .. 34 7 7 - 77 0 0 41 19 2 3 14 1 2 178 -21 .. .. .. 37 12 9 .. .. .. 34 41 30 Uncertainty in time = +/- 6 secs [Prediction of 2008 Jul 3.0] Data for the target star ------------------------ * name: 2UCAC 12080826 * constellation : Ara * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 17 33 28.7230 DE: -46 23 23.785 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .032, .031 ) * V mag [mag]: 12.6 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (599) Luisa approx. diameter [km]: 65 approx. diameter ["]: .070 distance from Earth [AU]: 1.28600 * orbital information: orbit source: Preston date of fit: 2008 Jul 02 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 876 number of rejected observations: 57 time covered by the observations: 1906 Apr 29 - 2008 Jun 16 1 sigma uncertainty ellipse (major, minor, PA): 0.039, 0.021, 111° remarks: * orbital elements for (599) Luisa : Mean anomaly = 325.84364754 deg Arg. of pericenter = 292.80950264 deg Long. of node = 44.67732394 deg Inclination = 16.66383383 deg Eccentricity = 0.29379332 Semimajor axis = 2.77255051 AU Perihelion dist = 1.95799369 AU Mag: H = 8.79, G = 0.15 Epoch of elements : MJD 54658.13500000 TDT (2008 Jul 11.135) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Jul 11 599 Luisa 3h 15.7m UT 12.6 17 33 28.723-46 23 23.782UCAC 12080826 0.0 11.8 65 9.0 1.286 -2.661 -4.20 -74.9752 -46.387 132.45 22.06 3.2623 -0.14999 0.97939 -4.02950 -0.61564 0.00226 0.00177 2000 324.1068782008 7 3.00000292.809503 44.677324 16.6638340.29379332 2.7725505 1.9579937 8.7 5.00.15 RATE 2.1349360 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.050 0.037 102 1.55 0.038 0 54650.5020080711_080826 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Jul 03, 00:53 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org