IOTA/IOTA-ES occultation update for (283) Emma / UCAC4 342-180357 event on 2024 Oct 20, 17:59 UT Visible from Summary ------- On 2024 Oct 20 UT, the 133.920334656976 km diameter asteroid (283) Emma will occult a 11.6 mag star in the constellation Sagittarius for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 2.54 mag to 14.06 mag (the magnitude of the asteroid) for at most 5.990 seconds. This update is based on, astrometry for the asteroid kindly provided by the IAU Minor Planet Center. This work has made use of data from the European Space Agency (ESA) mission Gaia (http://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, http://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. The event at a glimpse ---------------------- * Rank: 1 * date and approx. time of event: predicted path center does not land on Earth. * geocentric midpoint of event [JD]: 2460604.24939900 * magnitude of target star: 11.63 * magnitude drop [mag]: 2.54 * estimated maximum duration [s]: 5.990 * Moon: 85 % sunlit, 146° distance * Sun: 80° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 134 * 1 sigma uncertainty interval [path widths]: +/- 58.70 * 1 sigma uncertainty interval [seconds]: +/- 695.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 8.048, +/- 3.606) * 1 sigma uncertainty ellipse (major, minor, PA): (8.048", 3.606", 90°) * approx speed of asteroid's shadow [km/s]: 22.3779 * website for maps: http://www.asteroidoccultation.com Path Coordinates: No Lat/Long file for this path. Data for the target star ------------------------ * name: UCAC4 342-180357 * constellation : Sagittarius * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 19 16 09.8292 DE: -21 36 10.199 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 19 16 09.8291 DE: -21 36 10.199 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.100,0.100) * V mag [mag]: 11.6 * B mag [mag]: 12.5 * Diameter [mas]: 0.10 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (283) Emma asteroid class: asteroid system: multiple bodies approx. diameter [km]: 134 approx. diameter ["]: 0.068 distance from Earth [AU]: 2.72540 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#101 date of fit: 2023 Apr 24 source of used astrometry: MPC, JPL number of used observations: 0 number of rejected observations: 0 time covered by the observations: 1800 Jan 01 - 1800 Jan 01 1 sigma uncertainty ellipse (major, minor, PA): 0.018", 0.002", 74.293° remarks: * orbital elements for (283)Emma : Mean anomaly = 320.9922363660 deg Arg. of pericenter = 55.8482515690 deg Long. of node = 303.8574526901 deg Inclination = 7.9882372648 deg Eccentricity = 0.1441517224 Semimajor axis = 3.0488693740 AU Perihelion dist = 2.6093696025 AU Mag: H = 8.68, G = 0.15 Epoch of elements : MJD 60603.74939867 TDT (2024 Oct 20.7494) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#1012023Apr24 Binary solution 1 : NumInt,5.99,2024,10,20,17.985576,-3.436636,5.285918,12.277493,2.966176,0.005642,0.000764,-0.000001,0.000001 -10.0602,-21.5600,-93.62,-10.70,False UCAC4 342-180357,19.26939702,-21.6028331,12.47,11.63,11.18,0.1,0,,19.29391033,-21.5599794,2.54,2.55,0,0,0 283,Emma #1,14.06,134.118,2.7254,0,1,2.840,9.58,,4.0,0 S/2003 (283) 1,9,581,3.353000,0.1200,,,,, 0,320.8535,2024,10,20,55.8483,303.8575,7.9882,0.14415,3.04887,2.60937,8.67,5.0,0.15 2485.420,8.0483,3.6059,90,5.8271,Known errors + binary orbit,0.97,0,-1,-1 20241020_180357_Ma1,60140.65 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2023 Jul 15, 15:34 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org