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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 2459200.5 (2020-Dec-17.0) TDB
Reference: JPL 20 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1029000988292634 4.6046e-08  
a 5.203796380719445 1.0208e-07 au
q 4.668325218856051 2.8048e-07 au
i 9.541947266010043 5.3286e-06 deg
node 171.1752158399863 3.0703e-05 deg
peri 169.3954746002651 4.2017e-05 deg
M 280.7022971754706 3.201e-05 deg
tp 2460155.573894846711
(2023-Jul-30.07389485)
0.00040187 TDB
period 4335.896121803657
11.87
0.00012758
3.493e-07
d
yr
n .08302781936810938 2.443e-09 deg/d
Q 5.739267542582839 1.1258e-07 au
  Orbit Determination Parameters
   # obs. used (total)      611  
   data-arc span      15670 days (42.90 yr)  
   first obs. used      1977-10-11  
   last obs. used      2020-09-05  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .53275  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-13 02:26:00  

Additional Information
 Earth MOID = 3.65883 au 
 Jupiter MOID = .238352 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 12.48   n/a E2021B10  
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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