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18744 (1999 AU)
Classification: Main-belt Asteroid          SPK-ID: 2018744
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB
Reference: JPL 38 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1461611722199749 1.8647e-08  
a 2.355972698813879 7.6544e-09 au
q 2.011620967436984 4.629e-08 au
i 12.8100906834675 5.6003e-07 deg
node 310.4412678480724 3.5017e-06 deg
peri 281.217609440406 5.4022e-06 deg
M 283.6331844368671 6.6922e-06 deg
tp 2459480.692165411537
(2021-Sep-23.19216541)
2.533e-05 TDB
period 1320.850932493894
3.62
6.437e-06
1.762e-08
d
yr
n .2725515734923133 1.3283e-09 deg/d
Q 2.700324430190774 8.7732e-09 au
  Orbit Determination Parameters
   # obs. used (total)      2181  
   data-arc span      24199 days (66.25 yr)  
   first obs. used      1954-12-21  
   last obs. used      2021-03-23  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .43632  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-May-04 02:46:49  

Additional Information
 Earth MOID = 1.04465 au 
 Jupiter MOID = 2.454 au 
 T_jup = 3.507 
[ 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 13.79   n/a MPCxxxxx  
diameter diameter 8.087 km 0.047 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)  
rotation period rot_per 21.9 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Result based on fragmentary lightcurve(s), may be completely wrong.
Published Reference List:
[Behrend, R. (2004) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html]
geometric albedo albedo 0.212   0.019 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)  

18744 (1999 AU)          Discovered 1999-Jan-07 by Kobayashi, T. at Oizumi
Reference: 20001111/Numbers.arcLast Updated: 2004-04-19

Alternate Designations
 1999 AU = 1986 RZ9 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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