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16831 (1997 WM21)
Classification: Main-belt Asteroid          SPK-ID: 2016831
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB
Reference: JPL 33 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1475022691544694 1.5053e-08  
a 2.243330550242327 6.3653e-09 au
q 1.912434203618039 3.4105e-08 au
i 5.645812949726179 4.4659e-07 deg
node 232.411802514408 7.0578e-06 deg
peri 264.9021491052174 8.1122e-06 deg
M 259.342383840304 5.0012e-06 deg
tp 2459543.648791007908
(2021-Nov-25.14879101)
1.815e-05 TDB
period 1227.264954962352
3.36
5.2234e-06
1.43e-08
d
yr
n .2933351910232322 1.2485e-09 deg/d
Q 2.574226896866615 7.3042e-09 au
  Orbit Determination Parameters
   # obs. used (total)      2375  
   data-arc span      11075 days (30.32 yr)  
   first obs. used      1990-11-10  
   last obs. used      2021-03-07  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .41542  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-13 01:43:33  

Additional Information
 Earth MOID = .935746 au 
 Jupiter MOID = 2.48143 au 
 T_jup = 3.612 
[ 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 13.95   n/a E2021B10  
diameter diameter 4.346 km 0.086 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
rotation period rot_per 8.1072 h n/a LCDB (Rev. 2020-October); 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. (2014) http://www.asu.cas.cz/~ppravec/neo.htm]
[Oey, J.; Williams, H.; Groom, R.; Pray, D.; Benishek, V. (2017) Minor Planet Bull. 44, 193-199.]
geometric albedo albedo 0.215   0.032 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)  

16831 (1997 WM21)          Discovered 1997-Nov-30 by Kobayashi, T. at Oizumi
Reference: 20000913/Numbers.arcLast Updated: 2004-04-19

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Alternate Designations
 1997 WM21 = 1990 VP1 = 1992 JU1 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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