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JPL Small-Body Database Browser
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12421 Zhenya (1995 UH5)
Classification: Main-belt Asteroid          SPK-ID: 2012421
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 29 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1216716659826784 4.0806e-08  
a 2.450539198662185 9.8243e-09 au
q 2.152378011805099 9.8655e-08 au
i 5.556596180255777 3.8843e-06 deg
node 45.93665844868036 3.8473e-05 deg
peri 288.3238075535562 4.128e-05 deg
M 88.06323821590591 1.4771e-05 deg
tp 2458257.745584741942
5.7414e-05 TDB
period 1401.170249842276
n .2569280928142199 1.545e-09 deg/d
Q 2.74870038551927 1.102e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1589  
   data-arc span      10268 days (28.11 yr)  
   first obs. used      1991-09-14  
   last obs. used      2019-10-25  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .50976  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Nov-07 03:36:38  

Additional Information
 Earth MOID = 1.14965 au 
 Jupiter MOID = 2.5929 au 
 T_jup = 3.479 
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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 14.2   n/a MPO358750  
diameter diameter 7.964 km 0.055 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 7.70523 h n/a LCDB (Rev. 2019-January); Warner et al., 2009 sidereal period (not synodic); Result based on less than full coverage, so that the period may be wrong by 30 percent or so.
Published Reference List:
[Durech, J.; Hanus, J.; Ali-Lagoa, V. (2018) Astron. Astrophys. 617, A57.]
geometric albedo albedo 0.071   0.011 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

12421 Zhenya           Discovered 1995 Oct. 16 by T. V. Kryachko at the Zelenchukskaya Station of the Engelhardt Observatory.
Eugenia Krysina (b. 1952), a chemist who lives in Moscow, is a friend of the discoverer and displays a keen interest in astronomy, especially in minor planets. Zhenya is the diminutive form of Eugenia.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20010509/MPCPages.arcLast Updated: 2009-05-11

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Alternate Designations
 1995 UH5 = 1991 RO20 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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