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102554 (1999 US21)
Classification: Main-belt Asteroid          SPK-ID: 2102554
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB
Reference: JPL 14 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1141798121669786 9.2069e-08  
a 2.443121017128472 1.1924e-08 au
q 2.164165918291545 2.2841e-07 au
i 6.832361844081131 5.0717e-06 deg
node 35.67687884668427 5.1036e-05 deg
peri 137.639523271352 5.5489e-05 deg
M 60.82836459028839 2.0516e-05 deg
tp 2458964.821732968044
(2020-Apr-25.32173297)
7.9367e-05 TDB
period 1394.812711191156
3.82
1.0212e-05
2.796e-08
d
yr
n .2580991678033702 1.8896e-09 deg/d
Q 2.722076115965398 1.3286e-08 au
  Orbit Determination Parameters
   # obs. used (total)      360  
   data-arc span      8979 days (24.58 yr)  
   first obs. used      1995-10-20  
   last obs. used      2020-05-20  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .62115  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Feb-24 19:33:22  

Additional Information
 Earth MOID = 1.1733 au 
 Jupiter MOID = 2.24493 au 
 T_jup = 3.482 
[ 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 16.80   n/a E2021B55  

102554 (1999 US21)          Discovered 1999-Oct-31 by Spacewatch at Kitt Peak
Reference: 20051019/Numbers.arcLast Updated: 2005-10-26

[ show close-approach data ]
Alternate Designations
 1999 US21 = 1995 UF28 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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