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JPL Small-Body Database Browser
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2164 Lyalya (1972 RM2)
Classification: Main-belt Asteroid          SPK-ID: 2002164
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 .1316520887951653 3.5343e-08  
a 3.187928235121613 1.6424e-08 au
q 2.768230824038768 1.1445e-07 au
i 2.625514032651743 3.7635e-06 deg
node 115.7163334887294 8.8638e-05 deg
peri 196.9769829684758 8.9807e-05 deg
M 117.1526383676776 1.4807e-05 deg
tp 2457923.933010628568
8.5812e-05 TDB
period 2079.032274196863
n .1731574850799607 1.3381e-09 deg/d
Q 3.607625646204458 1.8586e-08 au
  Orbit Determination Parameters
   # obs. used (total)      2717  
   data-arc span      25669 days (70.28 yr)  
   first obs. used      1949-08-24  
   last obs. used      2019-12-04  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .4768  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Dec-13 21:11:23  

Additional Information
 Earth MOID = 1.7534 au 
 Jupiter MOID = 1.65574 au 
 T_jup = 3.182 
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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 11.9   n/a MPO340709  
diameter diameter 19.972 km 0.160 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 7.705 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:
[Ditteon, R.; Black, S.; Masner, Z.; Osborne, J.; Trent, L. (2018) Minor Planet Bull. 45, 338-340.]
geometric albedo albedo 0.084   0.011 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

2164 Lyalya           Discovered 1972 Sept. 11 by N. S. Chernykh at the Crimean Astrophysical Observatory.
Named in memory of Elena (Lyalya) Konstantinovna Ubijvovk (1918-1942), a student in astronomy at Kharkov University who perished with other members of the Resistance during the Great Patriotic War.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: MPC 5285Last Updated: 2007-10-23

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Alternate Designations
 1972 RM2 = 1949 QF1 = 1953 FJ = 1955 RW = 1955 SB2 = 1976 GO7 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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