+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   624 Hektor (1907 XM) Classification: Jupiter Trojan          SPK-ID: 2000624 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: JPL 65 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .0239082512269443 7.4601e-08   a 5.245924252443613 6.43e-08 AU q 5.120503377498672 4.0211e-07 AU i 18.17483009081847 8.4383e-06 deg node 342.8153130164678 2.2095e-05 deg peri 180.2838601821278 0.00014769 deg M 353.4466871581762 0.00014603 deg tp 2456480.389527021359 (2013-Jul-06.88952702) 0.0017803 JED period 4388.655085125634 12.02 8.0688e-05 2.209e-07 d yr n .08202968632010739 1.5082e-09 deg/d Q 5.371345127388556 6.5837e-08 AU   Orbit Determination Parameters    # obs. used (total)      1370      data-arc span      38787 days (106.19 yr)      first obs. used      1907-02-11      last obs. used      2013-04-22      planetary ephem.      DE405      SB-pert. ephem.      SB405-CPV-2      condition code      0      fit RMS      .55983      data source      ORB      producer      Otto Matic      solution date      2013-Apr-29 12:37:14   Additional Information  Earth MOID = 4.1283 AU   T_jup = 2.899  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 7.49 mag n/a PDS3 (MPC 17259)   diameter diameter 225 km n/a J.G. Williams 9-90   rotation period rot_per 6.924 h n/a Asteroid Lightcurve DataBase (Rev. 2013-May-01) Published Reference List: [Dunlap, J.L.; Gehrels, T. (1969) Astron. J. 74, 796-803.] [Magnusson, P. (1983) in Asteroids, Comets, Meteors. C.-I. Lagerkvist, H. Rickman, eds. Uppsala, pp. 77-85.] [Magnusson, P. (1986) Icarus 68, 1-39.] [Uchida, K.; Goguen, J.D. (1987) Bull. Amer. Astron. Soc. 19, 842.] [Michalowski, T. (1988) Acta Astronomica 38, 455-468.] [De Angelis, G. (1992) in Physical properties of small solar system bodies. A. Brahic, J.-C. Gerard, J. Surdej, eds. Universite de Liege, Institut d'Astrophysique, Liege, pp. 195-201.] [De Angelis, G. (1995) Planet. Space Sci. 43, 649-682.] [Szabo, Gy.; Sarneczky, K.; Kiss, L.L. (1999) in Proc. IAU Coll. 173, Evolution and Source Regions of Asteroids and Comets, 185-188.] [Kaasalainen, M.; Torppa, J.; Piironen, J. (2002) Astron. Astrophys. 383, L19-L22.] [Hamanowa, H.; Hamanowa, H. (2009) Minor Planet Bul. 36, 87-88.] [Stephens, R.D. (2009) Minor Planet Bul. 36, 59-62.] [Behrend, R. (2009) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] [Behrend, R. (2010) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] geometric albedo albedo 0.025   n/a EAR-A-5-DDR-ALBEDOS-V1.0:TRIAD TRIAD quality code 3 B-V BV .776 mag .027 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=9; phase (min.=3.84, mean=5.77, max.=7.78) deg. U-B UB .249 mag .034 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=7; phase (min.=3.84, mean=6.11, max.=7.78) deg. Tholen spectral type spec_T D   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 7 color indices; used ground-based radiometric albedo 624 Hektor (1907 XM)          Discovered 1907-Feb-10 by Kopff, A. at Heidelberg (024) Reference: DISCOVERY.DB Last Updated: 2003-08-29 Alternate Designations  1907 XM = 1948 VD  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] 2013-May-23 12:31 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin