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JPL Small-Body Database Browser
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11455 Richardstarr (1981 EN4)
Classification: Main-belt Asteroid          SPK-ID: 2011455
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ show orbit diagram ]
Orbital Elements at Epoch 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 24 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .0428575543291707 4.0164e-08  
a 3.063030217858496 2.0129e-08 au
q 2.931756233884734 1.1902e-07 au
i 9.906742728573976 4.4579e-06 deg
node 251.8291556023906 2.4147e-05 deg
peri 199.6411822508139 5.5088e-05 deg
M 125.0940186218861 5.009e-05 deg
tp 2457920.107696304773
(2017-Jun-15.60769631)
0.00027141 TDB
period 1958.057084013348
5.36
1.9302e-05
5.285e-08
d
yr
n .1838557225625532 1.8124e-09 deg/d
Q 3.194304201832259 2.0992e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1523  
   data-arc span      13975 days (38.26 yr)  
   first obs. used      1981-02-02  
   last obs. used      2019-05-09  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .50093  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-May-30 01:55:24  

Additional Information
 Earth MOID = 1.94982 au 
 Jupiter MOID = 2.02082 au 
 T_jup = 3.209 
[ show covariance matrix ]

Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 13.1   n/a MPO347616  
diameter diameter 5.132 km 0.125 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
rotation period rot_per 17.414 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:
[Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.]
geometric albedo albedo 0.558   0.111 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

11455 Richardstarr           Discovered 1981 Mar. 2 by S. J. Bus at Siding Spring.
Richard Starr (b. 1950) of the Catholic University of America is an expert in planetary X-ray, gamma-ray, and neutron spectroscopy, including their application to asteroid missions.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: MPC batch dated 2017-03-12Last Updated: 2017-04-19

Alternate Designations
 1981 EN4 = 1987 KR1 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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