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JPL Small-Body Database Browser
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9971 Ishihara (1993 HS)
Classification: Main-belt Asteroid          SPK-ID: 2009971
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 29 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1216260775170795 4.0231e-08  
a 2.181022150882303 8.5986e-09 au
q 1.915752981692624 8.6164e-08 au
i 2.747469395506215 4.0675e-06 deg
node 20.51941437829841 9.7794e-05 deg
peri 245.8210147522275 9.96e-05 deg
M 104.8528470577688 2.0864e-05 deg
tp 2458657.837745465196
6.7482e-05 TDB
period 1176.49081635871
n .3059947387555608 1.8096e-09 deg/d
Q 2.446291320071981 9.6445e-09 au
  Orbit Determination Parameters
   # obs. used (total)      1868  
   data-arc span      9993 days (27.36 yr)  
   first obs. used      1991-12-28  
   last obs. used      2019-05-08  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .48856  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-May-30 01:46:10  

Additional Information
 Earth MOID = .90193 au 
 Jupiter MOID = 2.61889 au 
 T_jup = 3.670 
[ 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 13.8   n/a MPO435794  
diameter diameter 5.012 km 0.069 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 6.715 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.]
[Durech, J.; Hanus, J.; Oszkiewsicz, D.; Vanco, R. (2016) Astron. Astrophys. 587, A48.]
geometric albedo albedo 0.233   0.028 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

9971 Ishihara           Discovered 1993 Apr. 16 by K. Endate and K. Watanabe at Kitami.
Takahiro Ishihara (b. 1961) was president of the Hiroshima Astronomical Society from 1987 to 1997 and is currently the society's director responsible for spreading awareness of astronomy. Comet observations are his particular personal passion.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20030106/MPCPages.arcLast Updated: 2003-10-02

Alternate Designations
 1993 HS = 1991 YC2 = 1996 EU1 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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