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JPL Small-Body Database Browser
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21774 O'Brien (1999 RR217)
Classification: Main-belt Asteroid          SPK-ID: 2021774
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 17 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .08358668128888097 3.4584e-08  
a 2.339830851558832 9.9057e-09 au
q 2.144252155899693 8.2144e-08 au
i 6.655354309343302 4.7051e-06 deg
node 155.7261862760926 3.3266e-05 deg
peri 266.7630950367729 4.3898e-05 deg
M 208.532383113633 2.8442e-05 deg
tp 2459550.537643941596
(2021-Dec-02.03764394)
0.00010417 TDB
period 1307.299579206603
3.58
8.3017e-06
2.273e-08
d
yr
n .2753768193044805 1.7487e-09 deg/d
Q 2.535409547217971 1.0734e-08 au
  Orbit Determination Parameters
   # obs. used (total)      840  
   data-arc span      9714 days (26.60 yr)  
   first obs. used      1992-09-22  
   last obs. used      2019-04-28  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .55584  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Jul-13 00:00:22  

Additional Information
 Earth MOID = 1.1692 au 
 Jupiter MOID = 2.68176 au 
 T_jup = 3.551 
[ 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 15.6   n/a MPO431751  

21774 O'Brien           Discovered 1999 Sept. 3 by the Lowell Observatory Near-Earth Object Search at the Anderson Mesa Station.
David P. O'Brien (b. 1976) is a planetary scientist at the Planetary Science Institute, Tucson. He studies collisional evolution of main-belt minor planets, cratering on (951) Gaspra and other objects, as well as primordial sculpting of the main belt during the planetary accretion process.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20080718/MPCPages.arcLast Updated: 2008-07-18

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Alternate Designations
 1999 RR217 = 1992 SG21 = 1998 HF143 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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