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JPL Small-Body Database Browser
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27125 Siyilee (1998 WZ20)
Classification: Main-belt Asteroid          SPK-ID: 2027125
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 15 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1707562679588655 4.1315e-08  
a 2.247080183120738 6.9318e-09 au
q 1.863377157246717 9.3937e-08 au
i 2.244892532141979 4.199e-06 deg
node 290.6469961697247 0.00012259 deg
peri 103.9716685973267 0.00012332 deg
M 154.7008476819984 1.3216e-05 deg
tp 2458471.791278985960
(2018-Dec-19.29127899)
4.4474e-05 TDB
period 1230.343223175515
3.37
5.6931e-06
1.559e-08
d
yr
n .2926012784228129 1.3539e-09 deg/d
Q 2.630783208994759 8.1155e-09 au
  Orbit Determination Parameters
   # obs. used (total)      885  
   data-arc span      10363 days (28.37 yr)  
   first obs. used      1991-09-15  
   last obs. used      2020-01-29  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .53809  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-23 00:57:29  

Additional Information
 Earth MOID = .871474 au 
 Jupiter MOID = 2.79575 au 
 T_jup = 3.610 
[ show covariance matrix ]

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 15.5   n/a MPO459046  

27125 Siyilee           Discovered 1998 Nov. 18 by the Lincoln Laboratory Near-Earth Asteroid Research Team at Socorro.
Si-Yi Ryan Lee (b. 1992) was a finalist in the 2010 Intel Science Talent Search, a science competition for high-school seniors, for his biochemistry project. He attends the North Carolina School Of Science And Mathematics, Durham, North Carolina, U.S.A.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20110319/MPCPages.arcLast Updated: 2011-03-23

[ show close-approach data ]
Alternate Designations
 1998 WZ20 = 1991 RK21 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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