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18646 (1998 ED21)
Classification: Main-belt Asteroid          SPK-ID: 2018646
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 25 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1067018073407916 3.5058e-08  
a 2.362382359001769 9.4981e-09 au
q 2.110311891666277 8.4287e-08 au
i 8.885696169443545 4.6514e-06 deg
node 157.3040449681158 2.4089e-05 deg
peri 296.0458058662965 3.4366e-05 deg
M 352.4497002040301 2.2314e-05 deg
tp 2458628.315406342092
(2019-May-24.81540634)
8.2196e-05 TDB
period 1326.24485831651
3.63
7.9984e-06
2.19e-08
d
yr
n .2714430881616926 1.637e-09 deg/d
Q 2.61445282633726 1.0512e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1201  
   data-arc span      11659 days (31.92 yr)  
   first obs. used      1987-02-23  
   last obs. used      2019-01-25  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .54428  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Jul-12 22:42:59  

Additional Information
 Earth MOID = 1.14412 au 
 Jupiter MOID = 2.53397 au 
 T_jup = 3.526 
[ 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 14.8   n/a MPO467912  
diameter diameter 4.386 km 0.163 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.084   0.011 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

18646 (1998 ED21)          Discovered 1998-Mar-03 by Elst, E. W. at La Silla
Reference: 20001111/Numbers.arcLast Updated: 2004-04-19

Alternate Designations
 1998 ED21 = 1987 DD3 = 1996 RS2 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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