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JPL Small-Body Database Browser
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21P/Giacobini-Zinner
Classification: Jupiter-family Comet [NEO]          SPK-ID: 1000032
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

[ show orbit diagram ]
:
Orbital Elements at Epoch 2458339.5 (2018-Aug-09.0) TDB
Reference: JPL K182/10 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .7104635508963024 5.817e-07  
a 3.498093382740213 7.3015e-06 au
q 1.012825536671743 1.1427e-07 au
i 31.99782625732268 8.3251e-06 deg
node 195.3919874642221 1.6469e-05 deg
peri 172.8605532582592 2.9575e-05 deg
M 355.1375239233932 1.7468e-05 deg
tp 2458371.777545507917
(2018-Sep-10.27754551)
1.9713e-05 TDB
period 2389.711784650855
6.54
0.007482
2.048e-05
d
yr
n .1506457817684475 4.7166e-07 deg/d
Q 5.983361228808683 1.2489e-05 au

Additional Model Parameters
 Parameter Value Uncertainty (1-sigma) 
A1 [EST] 4.521477115232857E-9 1.137E-10
A2 [EST] -4.467487858539592E-10 8.907E-11
A3 [EST] -3.130227413896412E-9 6.654E-11
  Orbit Determination Parameters
   # obs. used (total)      3833  
   data-arc span      2334 days (6.39 yr)  
   first obs. used      2012-11-19  
   last obs. used      2019-04-11  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      2  
   norm. resid. RMS      .67389  
   source      ORB  
   producer      Shantanu Naidu  
   solution date      2019-May-15 16:29:39  

Additional Information
 Earth MOID = .0163525 au 
 Jupiter MOID = .24681 au 
 T_jup = 2.466 
[ 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
comet total magnitude M1 13.1   0.9 K182/10 2 parameter fit from 1367 observations, autocmod 2.6q
comet total magnitude slope K1 9.   n/a K182/10 autocmod 2.6q
diameter diameter 2.0 km n/a Lamy,P.L.,Toth,I.,Fernandez,Y.R.,Weaver,H.A. (2004) Comets II, pp. 223-264  

21P/Giacobini-Zinner          Discovered 1900-Dec-20 by Giacobini, M. at Nice Observatory, France
Reference: comet.disLast Updated: 2003-08-29

[ show close-approach data ]
Alternate Designations
 Perihelion 
Year
(est.)
 New-Style 
Desig
Roman
 Numeral 
Year/
 Letter 
 1992.5       1992 IX   1991m 
 1986.0       1985 XIII   1984e 
 1979.4       1979 III   1978h 
 1972.9       1972 VI   1972d 
 1966.3       1966 I   1965g 
 1959.8       1959 VIII   1959b 
 1946.7       1946 V   1946c 
 1940.2       1940 I   1939l 
 1933.6       1933 III   1933c 
 1927.1       1926 VI   1926e 
 1914.0   21P/1913 U1   1913 V   1913e 
 1900.9   21P/1900 Y1   1900 III   1900c 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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