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JPL Small-Body Database Browser
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21071 (1991 PE7)
Classification: Main-belt Asteroid          SPK-ID: 2021071
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 25 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .05917550533667158 4.6022e-08  
a 2.554485784502235 1.4672e-08 au
q 2.403322797328971 1.1465e-07 au
i 14.61401798278987 6.3183e-06 deg
node 330.2785758459294 1.8452e-05 deg
peri 296.4190001438948 7.6037e-05 deg
M 68.70734345351748 7.7939e-05 deg
tp 2458715.887271722581
(2019-Aug-20.38727172)
0.00032281 TDB
period 1491.261006899333
4.08
1.2848e-05
3.518e-08
d
yr
n .2414064327669379 2.0798e-09 deg/d
Q 2.705648771675499 1.554e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1444  
   data-arc span      10243 days (28.04 yr)  
   first obs. used      1991-08-06  
   last obs. used      2019-08-22  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .53381  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Jan-29 01:28:45  

Additional Information
 Earth MOID = 1.42141 au 
 Jupiter MOID = 2.46254 au 
 T_jup = 3.391 
[ 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 13.9   n/a MPO492972  
diameter diameter 4.468 km 0.150 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.185   0.024 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

21071 (1991 PE7)          Discovered 1991-Aug-06 by Elst, E. W. at La Silla
Reference: 20010208/Numbers.arcLast Updated: 2004-04-19

[ show close-approach data ]
Alternate Designations
 1991 PE7 = 2000 XB36 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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