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JPL Small-Body Database Browser
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3789 Zhongguo (1928 UF)
Classification: Outer Main-belt Asteroid          SPK-ID: 2003789
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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For accurate long-term ephemerides, please instead use our Horizons system.This orbit viewer was implemented using two-body methods, and hence should not be used for determining accurate long-term trajectories (over several years or decades) or planetary encounter circumstances.

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Orbital Elements at Epoch 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 25 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1840085416561314 4.3844e-08  
a 3.284595746522059 1.8625e-08 au
q 2.680202073274602 1.4399e-07 au
i 2.746568485910259 3.761e-06 deg
node 86.95574841379937 0.00010252 deg
peri 313.2574542819706 0.00010314 deg
M 136.6889826375203 1.1471e-05 deg
tp 2457774.932996862033
6.77e-05 TDB
period 2174.30926322578
n .1655698230645939 1.4083e-09 deg/d
Q 3.888989419769515 2.2052e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1857  
   data-arc span      33070 days (90.54 yr)  
   first obs. used      1928-10-25  
   last obs. used      2019-05-11  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .47242  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-May-29 23:53:40  

Additional Information
 Earth MOID = 1.68878 au 
 Jupiter MOID = 1.5279 au 
 T_jup = 3.144 
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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 12.7   n/a MPO265977  
diameter diameter 14.006 km 0.181 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 3.840 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.]
geometric albedo albedo 0.099   0.013 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

3789 Zhongguo (1928 UF)          Discovered 1928-Oct-25 by Chang, Y. C. at Williams Bay
The original planet 1125 China was discovered 1928 Oct. 25 as 1928 UF by Y. C. Chang at Williams Bay and not observed again for many years. It was believed to have been recovered as 1957 UN1 on 1957 Oct. 30 by Chang at Nanking, but this identification was found to be incorrect. In agreement with the discoverer, the designation 1125 China was assigned to planet 1957 UN1. In 1986 C. M. Bardwell and S. Nakano independently identified 1986 QK1 with 1928 UF, and subsequently the permanent number 3789 was assigned to 1928 UF = 1986 QK1.
Note: "planet" implies "minor planet"
Reference: DISCOVERY.DBLast Updated: 2003-08-29

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Alternate Designations
 1928 UF = 1928 WC = 1975 VH1 = 1981 WY6 = 1986 QK1 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
FirstGov 2019-Dec-11 08:40 UT
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