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JPL Small-Body Database Browser
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7631 Vokrouhlicky (1981 WH)
Classification: Main-belt Asteroid          SPK-ID: 2007631
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

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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 24 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .2835442436999065 4.5291e-08  
a 2.370914226466207 6.9026e-09 au
q 1.698655145245497 1.0644e-07 au
i 4.030922425702286 3.7109e-06 deg
node 136.1472463823162 5.801e-05 deg
peri 273.8574585412086 5.8325e-05 deg
M 194.8460560785548 7.3021e-06 deg
tp 2459612.228394079106
2.8805e-05 TDB
period 1333.436045422118
n .2699792024041446 1.179e-09 deg/d
Q 3.043173307686917 8.8597e-09 au
  Orbit Determination Parameters
   # obs. used (total)      1946  
   data-arc span      24490 days (67.05 yr)  
   first obs. used      1953-01-09  
   last obs. used      2020-01-28  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .47565  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 18:34:33  

Additional Information
 Earth MOID = .714998 au 
 Jupiter MOID = 2.35671 au 
 T_jup = 3.486 
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Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 14.0   n/a MPO473871  
diameter diameter 3.834 km 0.196 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
geometric albedo albedo 0.242   0.026 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

7631 Vokrouhlický           Discovered 1981 Nov. 20 by E. Bowell at the Anderson Mesa Station of the Lowell Observatory.
Named in honor of David Vokrouhlický (b. 1966), a Czech physicist at Charles University, Prague, who has developed new physical models for the nongravitational forces acting on small minor planets and meteoroids. In particular, Vokrouhlický has studied the so-called Yarkovsky effect, which causes a slow orbital drift into main-belt resonances and is an important mechanism for transporting meteorites to Earth. Name proposed and citation written by P. Farinella.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 19990728/MPCPages.arcLast Updated: 2010-06-11

Alternate Designations
 1981 WH = 1975 BJ 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
FirstGov 2020-Mar-28 21:55 UT
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