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151P/Helin
Classification: Jupiter-family Comet          SPK-ID: 1000115
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ]

[ show orbit diagram ]
Orbital Elements at Epoch 2455165.5 (2009-Nov-30.0) TDB
Reference: JPL 33 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .5703733600209818 1.2038e-06  
a 5.809605650687495 1.3479e-06 au
q 2.495961355307986 7.3524e-06 au
i 4.735505041376388 4.7182e-05 deg
node 143.564015036869 0.00038758 deg
peri 215.4915432331094 0.0012176 deg
M 209.5705580268369 0.00020918 deg
tp 2457302.717647255686
(2015-Oct-07.21764726)
0.0037065 TDB
period 5114.679300274938
14.00
0.00178
4.873e-06
d
yr
n .07038564470320716 2.4495e-08 deg/d
Q 9.123249946067006 2.1167e-06 au

Additional Model Parameters
 Parameter Value Uncertainty (1-sigma) 
A1 [EST] 4.707174748429356E-8 3.571E-8
A2 [EST] -3.83674675929215E-10 1.749E-10
  Orbit Determination Parameters
   # obs. used (total)      412  
   data-arc span      10382 days (28.42 yr)  
   first obs. used      1987-08-24  
   last obs. used      2016-01-26  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-BIG16  
   condition code      1  
   norm. resid. RMS      .56738  
   source      ORB  
   producer      Otto Matic  
   solution date      2016-Apr-25 12:34:25  

Additional Information
 Earth MOID = 1.49415 au 
 Jupiter MOID = .234972 au 
 T_jup = 2.626 
[ show covariance matrix ]

Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
comet total magnitude M1 8.4   0.8 33 2 parameter fit from 196 observations, autocmod 2.6f
comet total magnitude slope K1 22.   n/a 33 autocmod 2.6f
comet nuclear magnitude M2 14.9   0.5 33 from 141 observations, autocmod 2.6f
comet nuclear magnitude slope K2 5.   n/a 33 autocmod 2.6f
comet nuclear phase coefficient PC 0.03   n/a 33 autocmod 2.6f
diameter diameter 8.4 km n/a Scotti,J (1994) BAAS 26:1375  

[ show close-approach data ]
Alternate Designations
 Perihelion 
Year
(est.)
 New-Style 
Desig
Roman
 Numeral 
Year/
 Letter 
 2001.8   151P/2001 M1       
 1987.8   151P/1987 Q3   1987 XVII   1987w 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ]
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