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91789 (1999 TH221)
Classification: Main-belt Asteroid          SPK-ID: 2091789
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 23 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1712322537495135 5.8548e-08  
a 2.758059516995203 1.9821e-08 au
q 2.28579076992482 1.6321e-07 au
i 10.00907778667232 6.0954e-06 deg
node 49.02887646226688 3.0848e-05 deg
peri 323.0269736455091 3.4664e-05 deg
M 182.9393921959837 1.843e-05 deg
tp 2459823.355028320188
(2022-Aug-31.85502832)
9.0007e-05 TDB
period 1673.030573368156
4.58
1.8035e-05
4.938e-08
d
yr
n .2151783749386275 2.3196e-09 deg/d
Q 3.230328264065586 2.3215e-08 au
  Orbit Determination Parameters
   # obs. used (total)      733  
   data-arc span      10362 days (28.37 yr)  
   first obs. used      1990-11-17  
   last obs. used      2019-04-01  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .58227  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Jul-13 07:24:13  

Additional Information
 Earth MOID = 1.29606 au 
 Jupiter MOID = 2.25132 au 
 T_jup = 3.299 
[ 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 14.9   n/a MPO337941  
diameter diameter 3.137 km 0.558 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.259   0.062 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

91789 (1999 TH221)          Discovered 1999-Oct-02 by LINEAR at Socorro
Reference: 20041028/Numbers.arcLast Updated: 2004-10-29

Alternate Designations
 1999 TH221 = 2001 AN38 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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