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JPL Small-Body Database Browser
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20912 (4129 P-L)
Classification: Main-belt Asteroid          SPK-ID: 2020912
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 23 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1958831044142828 4.6914e-08  
a 2.216102237871358 5.7178e-09 au
q 1.782005251817677 1.0521e-07 au
i 5.996680073908245 5.2858e-06 deg
node 189.3651704516124 3.458e-05 deg
peri 176.023526653775 3.5865e-05 deg
M 275.2614940348204 9.5655e-06 deg
tp 2458884.136042527570
(2020-Feb-04.63604253)
3.2439e-05 TDB
period 1204.989091404132
3.30
4.6635e-06
1.277e-08
d
yr
n .2987578913104554 1.1563e-09 deg/d
Q 2.65019922392504 6.8379e-09 au
  Orbit Determination Parameters
   # obs. used (total)      1316  
   data-arc span      21603 days (59.15 yr)  
   first obs. used      1960-09-24  
   last obs. used      2019-11-17  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .54901  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Dec-14 00:47:44  

Additional Information
 Earth MOID = .779532 au 
 Jupiter MOID = 2.80857 au 
 T_jup = 3.621 
[ 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 15.3   n/a MPO492971  
rotation period rot_per 4.959 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:
[Pravec, P.; Wolf, M.; Sarounova, L. (2016) http://www.asu.cas.cz/~ppravec/neo.htm]

20912 (4129 P-L)          Discovered 1960-Sep-24 by van Houten, C. J., van Houten-Groeneveld, I., Gehrels, T. at Palomar
Reference: 20010109/Numbers.arcLast Updated: 2004-04-19

Alternate Designations
 4129 P-L = 1993 SZ3 = 1999 JJ128 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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