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JPL Small-Body Database Browser
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617 Patroclus (A906 UL)
Classification: Jupiter Trojan          SPK-ID: 2000617
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 59 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1389665604832871 9.327e-09  
a 5.214559560207737 5.9051e-08 au
q 4.489910153690426 9.1048e-08 au
i 22.0517763307761 2.4129e-07 deg
node 44.34841429339916 1.7421e-06 deg
peri 307.8660818490041 5.4786e-06 deg
M 237.0071671908755 6.6602e-06 deg
tp 2460486.443097644020
0.00010283 TDB
period 4349.355185452411
n .0827708900859872 1.406e-09 deg/d
Q 5.939208966725047 6.7257e-08 au
  Orbit Determination Parameters
   # obs. used (total)      3955  
   data-arc span      7787 days (21.32 yr)  
   first obs. used      1998-04-22  
   last obs. used      2019-08-17  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .38855  
   source      ORB  
   producer      Ryan S. Park  
   solution date      2019-Oct-06 05:54:48  

Additional Information
 Earth MOID = 3.53757 au 
 Jupiter MOID = .189896 au 
 T_jup = 2.836 
[ 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 8.2   n/a MPO492756 IRAS observations used: 8
diameter diameter 140.362 km 0.868 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (  
rotation period rot_per 102.8 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Published Reference List:
[Behrend, R. (2005) Observatoire de Geneve web site,]
[Marchis, F.; Hestroffer, D.; Descamps, P.; Berthier, J.; et al. (2006) Nature 439, 565-567.]
[Mueller, M.; Marchis, F.; Emery, J.P.; Harris, A.W. (DLR); et al. (2010) Icarus 205, 505-515.]
[Oey, J. (2012) Minor Planet Bull. 39, 106-107.]
[Stephens, R.D.; Warner, B.D. (2018) Minor Planet Bull. 45, 343-347.]
geometric albedo albedo 0.047   0.003 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (  
B-V BV 0.677   0.013 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=5; phase (min.=2.24, mean=6.14, max.=8.61) deg.
U-B UB 0.215   0.045 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=7; phase (min.=2.24, mean=6.52, max.=8.61) deg.
Tholen spectral type spec_T P   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 7 color indices; used ground-based radiometric albedo

617 Patroclus (A906 UL)          Discovered 1906-Oct-17 by Kopff, A. at Heidelberg
Reference: DISCOVERY.DBLast Updated: 2003-08-29

Alternate Designations
 A906 UL = 1941 XC = 1962 NB 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
FirstGov 2020-Apr-08 06:41 UT
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