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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 2459000.5 (2020-May-31.0) TDB
Reference: JPL 26 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .04139724362722435 3.8811e-08  
a 3.06828205825775 2.0784e-08 au
q 2.941263638375013 1.1326e-07 au
i 9.891157311698365 4.3821e-06 deg
node 251.7981808009837 2.2721e-05 deg
peri 202.1054846499611 5.5345e-05 deg
M 195.9563483506059 5.1459e-05 deg
tp 2459895.036930984043
(2022-Nov-11.53693098)
0.00028232 TDB
period 1963.095139106804
5.37
1.9946e-05
5.461e-08
d
yr
n .1833838782585941 1.8633e-09 deg/d
Q 3.195300478140487 2.1644e-08 au
  Orbit Determination Parameters
   # obs. used (total)      2132  
   data-arc span      14058 days (38.49 yr)  
   first obs. used      1981-02-02  
   last obs. used      2019-07-31  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .43128  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 20:03:17  

Additional Information
 Earth MOID = 1.95996 au 
 Jupiter MOID = 2.01481 au 
 T_jup = 3.208 
[ 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-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 0.558   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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