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21330 Alanwhitman (1997 AT20)
Classification: Main-belt Asteroid          SPK-ID: 2021330
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

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For accurate long-term ephemerides, please instead use our Horizons system.This orbit viewer was implemented using two-body methods, and hence should not be used for determining accurate long-term trajectories (over several years or decades) or planetary encounter circumstances.


Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB
Reference: JPL 25 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .09568591314088452 4.1777e-08  
a 2.592391566240853 9.443e-09 au
q 2.34433621200637 1.0848e-07 au
i 4.3208146895289 3.1182e-06 deg
node 295.411345385415 6.0419e-05 deg
peri 57.61767859033013 6.3126e-05 deg
M 79.56114215899379 1.758e-05 deg
tp 2459059.563674676284
(2020-Jul-29.06367468)
7.4724e-05 TDB
period 1524.576870379002
4.17
8.3301e-06
2.281e-08
d
yr
n .2361310911863078 1.2902e-09 deg/d
Q 2.840446920475337 1.0347e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1513  
   data-arc span      8821 days (24.15 yr)  
   first obs. used      1997-01-11  
   last obs. used      2021-03-07  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .50809  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-13 03:43:32  

Additional Information
 Earth MOID = 1.34116 au 
 Jupiter MOID = 2.53551 au 
 T_jup = 3.408 
[ hide covariance matrix ]
Orbital Elements at Epoch 2457541.5 (2016-Jun-02.0) TDB
Reference: JPL 25 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .09745981004059366 4.1818e-08  
q 2.339808016333616 1.0889e-07 au
tp 2457536.230418819937
(2016-May-27.73041882)
7.5018e-05 TDB
node 295.4802190737342 6.0523e-05 deg
peri 57.8864277111619 6.3124e-05 deg
i 4.317137099988324 3.1157e-06 deg
  Orbit Determination Parameters
   # obs. used (total)      1513  
   data-arc span      8821 days (24.15 yr)  
   first obs. used      1997-01-11  
   last obs. used      2021-03-07  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .50809  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-13 03:43:32  

Additional Information
 Jupiter MOID = 2.53551 au 
 T_jup = 3.408 
Orbit Covariance (6×6)
  e q tp node peri i
e 1.74877014327895E-15 -4.539575702612372E-15 8.914018059132772E-13 -4.85119988052986E-15 1.867622557847997E-13 -2.295107436267651E-15
q -4.539575702612372E-15 1.185767460370367E-14 -2.491736078232356E-12 1.421139552928341E-14 -5.296529850266685E-13 6.09044917415189E-15
tp 8.914018059132772E-13 -2.491736078232356E-12 5.627662000531328E-9 -2.658128511497412E-12 1.373106451512278E-9 -2.635597765109219E-12
node -4.85119988052986E-15 1.421139552928341E-14 -2.658128511497412E-12 3.663090290283419E-9 -3.653205824508277E-9 2.73686754348254E-11
peri 1.867622557847997E-13 -5.296529850266685E-13 1.373106451512278E-9 -3.653205824508277E-9 3.984679720461354E-9 -2.790183540298736E-11
i -2.295107436267651E-15 6.09044917415189E-15 -2.635597765109219E-12 2.73686754348254E-11 -2.790183540298736E-11 9.707619879027558E-12

Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 14.66   n/a MPCxxxxx  
diameter diameter 3.394 km 0.676 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.292   0.116 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

21330 Alanwhitman           Discovered 1997 Jan. 11 by Spacewatch at Kitt Peak.
Alan Douglas Whitman (b. 1946) is a Canadian amateur astronomer and former weather service officer. He is a skillful observer and has written and lectured widely. Name suggested by R. and P. Jedicke.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: MPC batch dated 2016-06-20Last Updated: 2016-06-21

Alternate Designations
 1997 AT20 = 1999 RF28 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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