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Do comet groups exist?

Published online by Cambridge University Press:  12 April 2016

B.A. Lindblad
B.A. Lindblad*
Affiliation:
Lund Observatory, Box 43, S-221 00 Lund, Sweden

Abstract

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The phenomena of comet groups, i.e. sets of comets that exhibit similarity in their orbital elements, is investigated. A computer program based on the D-criterion of orbital similarity is used to search for comet pairs and groups. The reality of the groups is tested by making computer searches in random samples of comet orbits.

The data base for the study is 599 long-period comet orbits. The degree of orbital similarity within a comet group was first assumed to be identical to that encountered in meteor streams. The computer search at this level produced five comet pairs plus two groups with four and seven members, respectively. The latter two represented the eleven known members of the Kreutz group of sun-grazing comets. A comparison with searches in random samples showed that the two Kreutz groups were significant. There is a probability of 0.2 that the five comet pairs found in the real sample could be accidental formations.

In a second study the orbital similarity parameter Ds was varied and the number of comet groups found in the real and synthetic comet populations was compared at each level of Ds. Apart from the Kreutz group of comets, the number of groups detected in the real comet sample was for all levels of orbital similarity only slightly higher than the average found in the random samples. At the 2σ confidence level we conclude that comet groups exhibit similarity in their orbital elements, that is no greater than might be expected by chance.

Type
Section VI. Nongravitational Forces
Information
International Astronomical Union Colloquium , Volume 83: Dynamics of Comets: Their Origin and Evolution , 1985 , pp. 353 - 363
Copyright
Copyright © Cambridge University Press 1985

References

Hock, M.: 1865, Mon. Not. R. Astr. Soc. 24, 243.Google Scholar
Hock, M.: 1866, Mon. Not. R. Astr. Soc. 26, 204.Google Scholar
Hock, M.: 1867, Astr. Nachr., 70, 203.Google Scholar
Kramer, E.N., Musij, V.L. and Shestaka, I.S: 1979, Astron. Vestn., 13, 42.Google Scholar
Kresák, L.: 1982a, Bull. Astron. Inst. Czechosl., 33, 104.Google Scholar
Kresák, L.: 1982b, Bull. Astron. Inst. Czechosl., 33, 150.Google Scholar
Kreutz, H.: 1888, Publ. Sternwarte Kiel, no. 3.Google Scholar
Kreutz, H.: 1891, Publ. Sternwarte Kiel, no. 6.Google Scholar
Kreutz, H.: 1901, Astron. Abhandl., 1, 1.Google Scholar
Lindblad, B.A: 1971a, Smithson. Contr. Astrophys. 12, 1.Google Scholar
Lindblad, B.A: 1971b, ‘Meteor Streams’, in Space Res. XI, Akad. Verlag, Berlin.Google Scholar
Lindblad, B.A: 1974, in Asteroide, Comets, Meteoric Matter, IAU Coll. 22 (Nice), Cristescu, and Klepczynski, (Eds.), Bukarest, pp. 269–281.Google Scholar
Lindblad, B.A. and Southworth, R.B: 1971, in Gehrels, (Ed.), Physical Studies of Minor Planets, Washington, pp. 337–352.Google Scholar
Marsden, B.G: 1967, Astron. J., 72, 1170.Google Scholar
Marsden, B.G: 1982, Catalogue of Cometary Orbits, Fourth Ed., Cambridge.Google Scholar
Michels, D.J., Sheeley, N.R., Howard, R.A. and Koomen, M.J: 1982, Science, 215, 1097.Google Scholar
Öpik, E.S: 1971, Irish Astron. J., 10, 35.Google Scholar
Pickering, W.H: 1911, Harvard Ann., 61, 163.Google Scholar
Porter, J.G: 1952, ‘Comets and Meteor Streams’, Chapman and Hall, London.Google Scholar
Porter, J.G: 1961, Mem. British. Astron. Assoc., 39, No. 3.Google Scholar
Porter, J.G: 1963, in Middlehurst, and Kuiper, (Eds.) The Solar System IV, Chicago Univ. Press, pp. 550–572.Google Scholar
Porter, J.G: 1966, Mem. British. Astron. Assoc., 40, No. 2.Google Scholar
Porubcan, V.: 1968, Bull. Astron. Inst. Czechosl., 19, 327.Google Scholar
Porubcan, V.: 1977, Bull. Astron. Inst. Czechosl., 28, 257.Google Scholar
Sekanina, Z.: 1967, Acta Universitatis Carolinae - Mathematica et Physica, No. 2, 33–84, (Publ. Astron. Inst. Charles Univ., no. 51).Google Scholar
Sekanina, Z.: 1973, Icarus 18, 253.Google Scholar
Sheeley, N.R., Howard, R.A., Koomen, M.J. and Michels, D.J: 1982, Nature 300, 239.Google Scholar
Southworth, R.B. and Hawkins, G.S: 1963, Smithson. Contr, to Astrophys. 7, 261.Google Scholar
Weissman, P.R: 1983, Icarus 55, 448.Google Scholar
Whipple, F.L: 1977, Icarus 30, 736.CrossRefGoogle Scholar
Zausajev, A.F. and Galimova, A.G: 1982, Bull. Astrophys. Inst. Acad. Sci., Tadjik SSR, 72, 20.Google Scholar