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JPL Small-Body Database Browser
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281507 Johnellen (2008 TM9)
Classification: Main-belt Asteroid          SPK-ID: 2281507
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 9 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .06632779510173503 7.7954e-08  
a 2.603552757295352 3.6196e-08 au
q 2.430864843472909 1.9759e-07 au
i 13.92179217658087 7.6093e-06 deg
node 238.4976774325669 2.4383e-05 deg
peri 170.0162901782046 5.2562e-05 deg
M 134.5719098741209 4.5151e-05 deg
tp 2458026.912186297521
(2017-Sep-30.41218630)
0.00019181 TDB
period 1534.433249301772
4.20
3.1999e-05
8.761e-08
d
yr
n .2346143112864729 4.8927e-09 deg/d
Q 2.776240671117795 3.8597e-08 au
  Orbit Determination Parameters
   # obs. used (total)      235  
   data-arc span      6740 days (18.45 yr)  
   first obs. used      2000-10-25  
   last obs. used      2019-04-09  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .54476  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Jul-14 11:14:01  

Additional Information
 Earth MOID = 1.44229 au 
 Jupiter MOID = 2.56375 au 
 T_jup = 3.369 
[ 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 16.0   n/a MPO386178  

281507 Johnellen           Discovered 2008 Oct. 7 by D. McDonald at Celbridge.
Named for the parents of the discoverer, John and Ellen McDonald, for their inspiration and encouragement of his interest in astronomy.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: MPC batch dated 2019-05-18Last Updated: 2019-05-29
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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