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JPL Small-Body Database Browser
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1125 China (1957 UN1)
Classification: Main-belt Asteroid          SPK-ID: 2001125
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 2459000.5 (2020-May-31.0) TDB
Reference: JPL 36 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .2176065792089297 3.4218e-08  
a 3.127965979079297 1.1824e-08 au
q 2.447300002489941 1.0702e-07 au
i 3.040617478675923 3.9884e-06 deg
node 97.16370369644567 7.0577e-05 deg
peri 10.55165711030542 7.1087e-05 deg
M 33.34372612018608 8.0744e-06 deg
tp 2458813.344287509613
4.5104e-05 TDB
period 2020.651688827007
n .1781603440071261 1.0102e-09 deg/d
Q 3.808631955668653 1.4397e-08 au
  Orbit Determination Parameters
   # obs. used (total)      2760  
   data-arc span      40634 days (111.25 yr)  
   first obs. used      1909-01-27  
   last obs. used      2020-04-28  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .45862  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-May-20 01:19:31  

Additional Information
 Earth MOID = 1.46417 au 
 Jupiter MOID = 1.33738 au 
 T_jup = 3.175 
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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 11.6   n/a MPO267711  
diameter diameter 26.084 km 0.199 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 5.367 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Published Reference List:
[Menzies, K.T. (2009) Minor Planet Bull. 36, 83-84.]
[Stephens, R.D. (2014) Minor Planet Bull. 41, 92-95.]
[Hanus, J.; Durech, J.; Oszkiewicz, D.A.; Behrend, R.; et al. (2016) Astron. Astrophys. 586, A108.]
geometric albedo albedo 0.078   0.022 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

1125 China (1957 UN1)          Discovered 1957-Oct-30 by Chang, Y. C. at Nanking
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
 1957 UN1 = 1959 EL = 1971 KX = 1974 VM = A909 BE 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
FirstGov 2020-May-30 03:55 UT
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