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18281 Tros (4317 T-3)
Classification: Jupiter Trojan          SPK-ID: 2018281
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 18 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1025959661762891 5.1938e-08  
a 5.203157605926551 1.0972e-07 au
q 4.669334624179009 2.9469e-07 au
i 9.542074740544152 6.023e-06 deg
node 171.1779426246994 3.1298e-05 deg
peri 169.4548788955424 4.2762e-05 deg
M 263.9969300029052 3.2993e-05 deg
tp 2460156.563045635133
(2023-Jul-31.06304563)
0.0004198 TDB
period 4335.097788448245
11.87
0.00013713
3.754e-07
d
yr
n .0830431094217283 2.6268e-09 deg/d
Q 5.736980587674093 1.2098e-07 au
  Orbit Determination Parameters
   # obs. used (total)      567  
   data-arc span      15538 days (42.54 yr)  
   first obs. used      1977-10-11  
   last obs. used      2020-04-26  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .54671  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-May-20 04:47:16  

Additional Information
 Earth MOID = 3.66169 au 
 Jupiter MOID = .237586 au 
 T_jup = 2.962 
[ 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 12.4   n/a MPO435869  
diameter diameter 13.976 km 0.738 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2011ApJ...742...40G)  
geometric albedo albedo 0.099   0.024 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2011ApJ...742...40G)  

18281 Tros           Discovered 1977 Oct. 16 by C. J. van Houten and I. van Houten-Groeneveld on Palomar Schmidt plates taken by T. Gehrels.
Tros was a grandson of Dardanos. His country was named Troas after him, and its principal city was Troy.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20010309/MPCPages.arcLast Updated: 2009-05-11

Alternate Designations
 4317 T-3 = 1988 RK12 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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