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52249 (1981 EK21)
Classification: Main-belt Asteroid          SPK-ID: 2052249
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 24 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .08436521978901473 3.8101e-08  
a 2.754587143712152 1.5487e-08 au
q 2.522195793904882 1.0486e-07 au
i 7.472034856497039 5.497e-06 deg
node 346.368155768639 2.8754e-05 deg
peri 260.7714278291842 4.3448e-05 deg
M 142.9786760828598 3.2275e-05 deg
tp 2458337.288616715305
(2018-Aug-06.78861672)
0.00014971 TDB
period 1669.872071301913
4.57
1.4082e-05
3.855e-08
d
yr
n .2155853769800022 1.8181e-09 deg/d
Q 2.986978493519422 1.6793e-08 au
  Orbit Determination Parameters
   # obs. used (total)      811  
   data-arc span      14164 days (38.78 yr)  
   first obs. used      1981-02-09  
   last obs. used      2019-11-21  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .55372  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Dec-14 04:59:33  

Additional Information
 Earth MOID = 1.5226 au 
 Jupiter MOID = 2.07557 au 
 T_jup = 3.327 
[ show covariance matrix ]

Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 15.1   n/a MPO449338  
diameter diameter 6.038 km 0.126 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.044   0.009 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

52249 (1981 EK21)          Discovered 1981-Mar-02 by Bus, S. J. at Siding Spring
Reference: 20030216/Numbers.arcLast Updated: 2004-04-19

[ show close-approach data ]
Alternate Designations
 1981 EK21 = 1999 CT34 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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