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JPL Small-Body Database Browser
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39979 (1998 HT12)
Classification: Main-belt Asteroid          SPK-ID: 2039979
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 25 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .2212733391453739 4.5213e-08  
a 2.377077603701052 1.0959e-08 au
q 1.851093704922437 1.0596e-07 au
i 24.84953640115655 5.7467e-06 deg
node 71.32053533650638 1.3992e-05 deg
peri 28.95625849522114 2.0566e-05 deg
M 88.45982913020254 1.4515e-05 deg
tp 2458671.567290380011
(2019-Jul-07.06729038)
5.311e-05 TDB
period 1338.638980286769
3.66
9.2568e-06
2.534e-08
d
yr
n .268929864811556 1.8597e-09 deg/d
Q 2.903061502479668 1.3383e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1087  
   data-arc span      10495 days (28.73 yr)  
   first obs. used      1991-05-13  
   last obs. used      2020-02-05  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .43564  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-23 05:40:50  

Additional Information
 Earth MOID = .889412 au 
 Jupiter MOID = 2.42597 au 
 T_jup = 3.385 
[ 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 14.0   n/a MPO452723  
diameter diameter 5.392 km 0.349 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
rotation period rot_per 8.103 h n/a LCDB (Rev. 2019-August); 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 0.221   0.050 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

39979 (1998 HT12)          Discovered 1998-Apr-22 by JPL/GEODSS NEAT at Haleakala
Reference: 20020526/Numbers.arcLast Updated: 2004-04-19

Alternate Designations
 1998 HT12 = 1987 FH1 = 1991 JD5 = 2000 WA11 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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