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181959 (1999 UG21)
Classification: Main-belt Asteroid          SPK-ID: 2181959
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 .1373022563570488 5.5409e-08  
a 2.282197044328858 1.003e-08 au
q 1.968846240691118 1.2452e-07 au
i 2.923208242418248 5.547e-06 deg
node 157.1361638680732 0.00011559 deg
peri 276.1246349198516 0.00011899 deg
M 9.1487718373034 2.4186e-05 deg
tp 2459168.497166593984
(2020-Nov-14.99716659)
8.4587e-05 TDB
period 1259.296901381851
3.45
8.302e-06
2.273e-08
d
yr
n .2858738075230433 1.8846e-09 deg/d
Q 2.595547847966598 1.1408e-08 au
  Orbit Determination Parameters
   # obs. used (total)      324  
   data-arc span      10344 days (28.32 yr)  
   first obs. used      1992-09-23  
   last obs. used      2021-01-18  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .55871  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-13 21:32:45  

Additional Information
 Earth MOID = .985721 au 
 Jupiter MOID = 2.64641 au 
 T_jup = 3.590 
[ 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 17.3   n/a MPO440020  

181959 (1999 UG21)          Discovered 1999-Oct-31 by Spacewatch at Kitt Peak
Reference: 20080420/Numbers.arcLast Updated: 2008-04-23

[ show close-approach data ]
Alternate Designations
 1999 UG21 = 1999 TO327 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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