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8957 Koujounotsuki (1998 FM125)
Classification: Main-belt Asteroid          SPK-ID: 2008957
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 28 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1558344331582339 3.582e-08  
a 2.267281055772683 7.8321e-09 au
q 1.913960597635945 8.0095e-08 au
i 3.072779864218111 4.2129e-06 deg
node 300.6114108103193 8.3572e-05 deg
peri 154.1616199455012 8.4984e-05 deg
M 254.7158961496656 1.5611e-05 deg
tp 2459365.184050609538
5.4598e-05 TDB
period 1246.971322528064
n .2886995021426389 1.4959e-09 deg/d
Q 2.620601513909421 9.0526e-09 au
  Orbit Determination Parameters
   # obs. used (total)      1527  
   data-arc span      18211 days (49.86 yr)  
   first obs. used      1969-10-16  
   last obs. used      2019-08-26  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .48882  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 19:07:56  

Additional Information
 Earth MOID = .931292 au 
 Jupiter MOID = 2.54138 au 
 T_jup = 3.597 
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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 14.1   n/a MPO337333  
diameter diameter 4.066 km 0.587 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 87.224 h n/a LCDB (Rev. 2019-August); 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 0.265   0.116 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

8957 Koujounotsuki           Discovered 1998 Mar. 22 by T. Seki at Geisei.
Named for a song composed in 1901 by Rentaro Taki (1879-1903). In English, the song's title is "The Moon over the Ruins of a Castle". The reference is specifically to Oka castle, symbol of Takeda City, in Oita Prefecture.
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

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Alternate Designations
 1998 FM125 = 1969 UH = 1976 YF2 = 1984 BE5 = 1986 TX18 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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