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JPL Small-Body Database Browser
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20428 (1998 WG20)
Classification: Jupiter Trojan          SPK-ID: 2020428
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 22 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1470732103684711 8.087e-08  
a 5.206371339752843 1.3024e-07 au
q 4.440653592444995 4.594e-07 au
i 21.03375067721558 8.0444e-06 deg
node 45.35291718237247 1.5915e-05 deg
peri 5.460574981568447 2.6846e-05 deg
M 292.676053108172 2.7948e-05 deg
tp 2459811.962034763025
(2022-Aug-20.46203476)
0.00035817 TDB
period 4339.114772698337
11.88
0.00016282
4.458e-07
d
yr
n .08296623133020498 3.1132e-09 deg/d
Q 5.972089087060692 1.4939e-07 au
  Orbit Determination Parameters
   # obs. used (total)      893  
   data-arc span      12852 days (35.19 yr)  
   first obs. used      1984-08-21  
   last obs. used      2019-10-29  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .58015  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Nov-07 04:23:14  

Additional Information
 Earth MOID = 3.45168 au 
 Jupiter MOID = .528058 au 
 T_jup = 2.846 
[ 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 11.0   n/a MPO492967  
diameter diameter 27.176 km 3.231 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2012ApJ...759...49G)  
rotation period rot_per 14.813 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Result based on less than full coverage, so that the period may be wrong by 30 percent or so.
Published Reference List:
[Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.]
geometric albedo albedo 0.095   0.015 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2012ApJ...759...49G)  

20428 (1998 WG20)          Discovered 1998-Nov-18 by LINEAR at Socorro
Reference: 20010109/Numbers.arcLast Updated: 2004-04-19

Alternate Designations
 1998 WG20 = 1999 YY6 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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