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JPL Small-Body Database Browser
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305949 (2009 HT21)
Classification: Main-belt Asteroid          SPK-ID: 2305949
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

[ show orbit diagram ]
Orbital Elements at Epoch 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 12 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1036194054741626 9.278e-08  
a 3.192813388205216 4.7756e-08 au
q 2.861975963129444 2.821e-07 au
i 6.97672586448971 9.5118e-06 deg
node 30.44860699347798 5.0403e-05 deg
peri 193.7528898845038 5.8609e-05 deg
M 258.8713928939562 3.1021e-05 deg
tp 2459185.869722630231
(2020-Dec-02.36972263)
0.00018415 TDB
period 2083.812940545177
5.71
4.6752e-05
1.28e-07
d
yr
n .1727602286152495 3.876e-09 deg/d
Q 3.523650813280987 5.2704e-08 au
  Orbit Determination Parameters
   # obs. used (total)      218  
   data-arc span      9751 days (26.70 yr)  
   first obs. used      1992-04-24  
   last obs. used      2019-01-04  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .60208  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Jul-14 12:10:38  

Additional Information
 Earth MOID = 1.85393 au 
 Jupiter MOID = 1.45691 au 
 T_jup = 3.176 
[ 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 15.5   n/a MPO427633  

305949 (2009 HT21)          Discovered 2009-Apr-16 by CSS at Catalina
Reference: 20111110/Numbers.arcLast Updated: 2011-11-14

[ show close-approach data ]
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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