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90690 (1981 EK31)
Classification: Main-belt Asteroid          SPK-ID: 2090690
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB
Reference: JPL 22 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .08900510827631834 6.9476e-08  
a 2.623658051041646 1.8531e-08 au
q 2.39013908212865 1.7933e-07 au
i 10.21980676202379 6.755e-06 deg
node 350.3594756915369 3.0044e-05 deg
peri 20.1861840061268 4.137e-05 deg
M 342.3940318578234 3.0295e-05 deg
tp 2459472.413092721883
(2021-Sep-14.91309272)
0.00013085 TDB
period 1552.241442173782
4.25
1.6446e-05
4.503e-08
d
yr
n .2319226830433354 2.4572e-09 deg/d
Q 2.857177019954642 2.0181e-08 au
  Orbit Determination Parameters
   # obs. used (total)      590  
   data-arc span      14782 days (40.47 yr)  
   first obs. used      1981-02-12  
   last obs. used      2021-08-03  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .59408  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Aug-25 23:32:11  

Additional Information
 Earth MOID = 1.3902 au 
 Jupiter MOID = 2.56872 au 
 T_jup = 3.375 
[ 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 15.26   n/a MPO637234  
diameter diameter 3.887 km 0.271 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.117   0.021 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

90690 (1981 EK31)          Discovered 1981-Mar-02 by Bus, S. J. at Siding Spring
Reference: 20041028/Numbers.arcLast Updated: 2004-10-29

Alternate Designations
 1981 EK31 = 2000 WQ6 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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