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8625 Simonhelberg (1981 EX15)
Classification: Main-belt Asteroid          SPK-ID: 2008625
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB
Reference: JPL 29 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .07975421155598537 4.7172e-08  
a 2.605331870322727 1.4015e-08 au
q 2.397545681163457 1.2891e-07 au
i 3.631228368888934 4.3688e-06 deg
node 326.4603502326484 6.0943e-05 deg
peri 57.43931768894814 6.6192e-05 deg
M 318.2755402810666 2.8492e-05 deg
tp 2459378.525094951508
(2021-Jun-13.02509495)
0.00012232 TDB
period 1536.006328524392
4.21
1.2394e-05
3.393e-08
d
yr
n .2343740343477909 1.8912e-09 deg/d
Q 2.813118059481997 1.5133e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1408  
   data-arc span      24554 days (67.23 yr)  
   first obs. used      1953-10-01  
   last obs. used      2020-12-22  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .46949  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-12 20:45:58  

Additional Information
 Earth MOID = 1.40153 au 
 Jupiter MOID = 2.5421 au 
 T_jup = 3.405 
[ 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 14.55   n/a E2021B10  
diameter diameter 3.694 km 0.865 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
rotation period rot_per 5.27 h n/a LCDB (Rev. 2020-October); 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:
[Chang, C.K.; Ip, W.-H.; Lin, H.-W.; Cheng, Y.C.; et al. (2015) Astrophys. J. Supp. Ser. 219, A27.]
[Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.]
geometric albedo albedo 0.247   0.114 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

8625 Simonhelberg           Discovered 1981 Mar. 1 by S. J. Bus at Siding Spring.
American actor and comedian Simon Maxwell Helberg (b. 1980) portrays the fictional Caltech aerospace engineer Howard Wolowitz in the television sitcom "The Big Bang Theory".
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 2015-08-29Last Updated: 2015-09-02

[ show close-approach data ]
Alternate Designations
 1981 EX15 = 1949 SE = 1978 NH5 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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