+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   21602 Ialmenus (1998 YW1) Classification: Jupiter Trojan          SPK-ID: 2021602 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 20 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .06023472162014865 5.4034e-08   a 5.210773447569308 1.1676e-07 au q 4.896903959529308 3.062e-07 au i 7.939058663479836 5.4838e-06 deg node 309.307751165082 4.5066e-05 deg peri 194.0875396236543 7.4157e-05 deg M 242.6248165716071 6.2613e-05 deg tp 2460617.029088642717 (2024-Nov-02.52908864) 0.00078864 TDB period 4344.619169200139 11.89 0.00014602 3.998e-07 d yr n .08286111762156528 2.785e-09 deg/d Q 5.524642935609308 1.2379e-07 au   Orbit Determination Parameters    # obs. used (total)      714      data-arc span      13610 days (37.26 yr)      first obs. used      1983-10-08      last obs. used      2021-01-11      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .51501      source      ORB      producer      Otto Matic      solution date      2021-Feb-24 02:53:34   Additional Information  Earth MOID = 3.91015 au   Jupiter MOID = .351063 au   T_jup = 2.977  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 12.12   n/a E2021B10   diameter diameter 16.353 km 1.174 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2011ApJ...742...40G)   geometric albedo albedo 0.151   0.038 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2011ApJ...742...40G)   21602 Ialmenus           Discovered 1998 Dec. 17 by M. Tichy and Z. Moravec at Klet. Ialmenus was one of the Achaean leaders and one of those who entered Troy in the Wooden Horse. He was the son of Ares and Astyoche. He is counted among the Argonauts and the suitors of Helen. The citation was prepared by J. Ticha. NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: 20010509/MPCPages.arc Last Updated: 2009-05-11 Alternate Designations  1998 YW1 = 1989 AD5  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Apr-10 20:37 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin