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JPL Small-Body Database Browser
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624 Hektor (A907 CF)
Classification: Jupiter Trojan          SPK-ID: 2000624
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

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For accurate long-term ephemerides, please instead use our Horizons system.This orbit viewer was implemented using two-body methods, and hence should not be used for determining accurate long-term trajectories (over several years or decades) or planetary encounter circumstances.

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Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 96 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .02279654721206953 5.3558e-08  
a 5.262259750367621 6.2146e-08 au
q 5.142298397526192 2.7613e-07 au
i 18.15769723602151 6.1111e-06 deg
node 342.7910347058902 1.4241e-05 deg
peri 184.24388269331 0.00010784 deg
M 202.5084918795885 0.0001091 deg
tp 2460929.407892536709
0.001351 TDB
period 4409.170053678708
n .08164801892810662 1.4464e-09 deg/d
Q 5.382221103209049 6.3562e-08 au
  Orbit Determination Parameters
   # obs. used (total)      3206  
   data-arc span      41257 days (112.96 yr)  
   first obs. used      1907-02-11  
   last obs. used      2020-01-26  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .36233  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 15:32:41  

Additional Information
 Earth MOID = 4.14985 au 
 Jupiter MOID = .272419 au 
 T_jup = 2.899 
[ 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 7.3   n/a MPO452166  
diameter diameter 225 km n/a J.G. Williams 9-90  
rotation period rot_per 6.924 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 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.]
[Lacerda, P.; Jewitt, D.C. (2007) Astron. J. 133, 1393-1408.]
[Behrend, R. (2009) Observatoire de Geneve web site,]
[Hamanowa, H.; Hamanowa, H. (2009) Minor Planet Bull. 36, 87-88.]
[Stephens, R.D. (2009) Minor Planet Bull. 36, 59-62.]
[Behrend, R. (2010) Observatoire de Geneve web site,]
[Behrend, R. (2013) Observatoire de Geneve web site,]
[Gorshanov, D.L.; Arkharov, A.A.; Larionov, V.M. (2014) Solar System Research 48, 202-211.]
[Marchis, F.; Durech, J.; Castillo-Rogez, J.; Vachier, F.; et al. (2014). Astrophys. J. Let. 783, L37.]
[Stephens, R.D.; Coley, D.R.; French, L.M. (2014) Minor Planet Bull. 41, 210-212.]
[Hanus, J.; Delbo, M.; Durech, J.; Ali-Lagoa, V. (2015) Icarus 256, 101-116.]
geometric albedo albedo 0.025   n/a EAR-A-5-DDR-ALBEDOS-V1.0:TRIAD TRIAD quality code 3
B-V BV 0.776   0.027 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=9; phase (min.=3.84, mean=5.77, max.=7.78) deg.
U-B UB 0.249   0.034 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #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 (A907 CF)          Discovered 1907-Feb-10 by Kopff, A. at Heidelberg
Reference: DISCOVERY.DBLast Updated: 2003-08-29

Alternate Designations
 A907 CF = 1948 VD 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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