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JPL Small-Body Database Browser
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20484 Janetsong (1999 NL41)
Classification: Main-belt Asteroid          SPK-ID: 2020484
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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Orbital Elements at Epoch 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 32 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .09360900156192618 5.9349e-08  
a 2.525423795598745 1.1596e-08 au
q 2.289021395572016 1.5205e-07 au
i 7.126779514588359 4.1136e-06 deg
node 94.47818481150047 3.7676e-05 deg
peri 237.2170440214347 4.1995e-05 deg
M 318.0209262281829 1.8088e-05 deg
tp 2458771.434678920718
(2019-Oct-14.93467892)
7.3607e-05 TDB
period 1465.884758342886
4.01
1.0096e-05
2.764e-08
d
yr
n .2455854718122338 1.6914e-09 deg/d
Q 2.761826195625474 1.2681e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1547  
   data-arc span      9820 days (26.89 yr)  
   first obs. used      1993-01-16  
   last obs. used      2019-12-06  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .51787  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Dec-14 00:44:29  

Additional Information
 Earth MOID = 1.28595 au 
 Jupiter MOID = 2.5146 au 
 T_jup = 3.437 
[ 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 13.8   n/a MPO344464  
diameter diameter 4.216 km 0.306 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
rotation period rot_per 4.358 h n/a LCDB (Rev. 2019-January); 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:
[Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.]
geometric albedo albedo 0.361   0.054 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

20484 Janetsong           Discovered 1999 July 14 by the Lincoln Laboratory Near-Earth Asteroid Research Team at Socorro.
Janet Song (b. 1991) is a finalist in the 2004 Discovery Channel Young Scientist Challenge (DCYSC), a middle school science competition, for her biochemistry, medicine, health, and microbiology project. She attends the Arcola Intermediate School, Norristown, Pennsylvania.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20041028/MPCPages.arcLast Updated: 2004-10-29

[ show close-approach data ]
Alternate Designations
 1999 NL41 = 1993 BX1 = 1998 HY136 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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