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39494 (1981 EM11)
Classification: Main-belt Asteroid          SPK-ID: 2039494
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ show orbit diagram ]
Orbital Elements at Epoch 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 19 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .06476502284237989 4.5397e-08  
a 2.299585304970474 9.585e-09 au
q 2.15065261016606 1.036e-07 au
i 6.017916848808085 4.9345e-06 deg
node 304.1892009817691 3.608e-05 deg
peri 172.745365460317 5.0228e-05 deg
M 27.29226272552903 3.3091e-05 deg
tp 2458503.937220875080
(2019-Jan-20.43722088)
0.00011708 TDB
period 1273.716321529274
3.49
7.9635e-06
2.18e-08
d
yr
n .28263750249174 1.7671e-09 deg/d
Q 2.448517999774888 1.0206e-08 au
  Orbit Determination Parameters
   # obs. used (total)      980  
   data-arc span      13968 days (38.24 yr)  
   first obs. used      1981-02-02  
   last obs. used      2019-05-02  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .54914  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Jul-13 02:06:58  

Additional Information
 Earth MOID = 1.16725 au 
 Jupiter MOID = 2.60254 au 
 T_jup = 3.582 
[ 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 15.5   n/a MPO474252  
rotation period rot_per 7.353 h n/a LCDB (Rev. 2019-January); 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.]

39494 (1981 EM11)          Discovered 1981-Mar-07 by Bus, S. J. at Siding Spring
Reference: 20020526/Numbers.arcLast Updated: 2004-04-19
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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