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JPL Small-Body Database Browser
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2207 Antenor (1977 QH1)
Classification: Jupiter Trojan          SPK-ID: 2002207
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 36 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .01480562671973958 4.0392e-08  
a 5.156548308273954 6.3785e-08 au
q 5.080202378859345 1.9019e-07 au
i 6.800556458619616 4.7011e-06 deg
node 159.0693608576524 3.3367e-05 deg
peri 310.1244890131263 0.0001776 deg
M 135.7396062208606 0.0001722 deg
tp 2457387.846189284903
0.0020491 TDB
period 4276.97845913019
n .08417157192632045 1.5618e-09 deg/d
Q 5.232894237688563 6.4729e-08 au
  Orbit Determination Parameters
   # obs. used (total)      2807  
   data-arc span      22244 days (60.90 yr)  
   first obs. used      1959-03-11  
   last obs. used      2020-02-03  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .45984  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 16:15:34  

Additional Information
 Earth MOID = 4.10093 au 
 Jupiter MOID = .219454 au 
 T_jup = 2.986 
[ 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 8.9   n/a MPO492776 IRAS observations used: 9
diameter diameter 97.658 km 0.504 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (  
rotation period rot_per 7.9647 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Published Reference List:
[Gonano, M.; Di Martino, M.; Mottola, S.; Neukum, G. (1991) Adv. Space Res. 11, no. 12, 197-200.]
[Mottola, S.; Di Martino, M.; Erikson, A.; Gonano-Beurer, M.; et al. (2011) Astron. J. 141, A170.]
[Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.]
[Stephens, R.D.; Coley, D.R.; French, L.M. (2016) Minor Planet Bull. 43, 265-270.]
[Stephens, R.D.; Coley, D.R. (2017) Minor Planet Bull. 44, 252-257.]
[Stephens, R.D.; Pravec, P.; Kueakova, H.; Kusnirak, P.; et al. (2018) Minor Planet Bull. 45, 341-342.]
[Stephens, R. D.; Warner, B. D. (2019) MPB 46, 315-317.]
geometric albedo albedo 0.051   0.003 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (  
B-V BV 0.733   0.035 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=3; phase (min.=1.44, mean=2.56, max.=4.58) deg.
U-B UB 0.232   0.038 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=3; phase (min.=1.44, mean=2.56, max.=4.58) 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

2207 Antenor           Discovered 1977 Aug. 19 by N. S. Chernykh at the Crimean Astrophysical Observatory.
This Trojan planet is named for the Trojan hero and sage who called for peace with the Greeks. He advised the citizens of Troy to put an end to the war by returning the kidnapped Helen to her husband Menelaus.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: MPC 5849Last Updated: 2006-03-21

Alternate Designations
 1977 QH1 = 1959 EM = 1971 BE1 = 1978 UU 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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