Short-period comets: Primordial bodies or collisional fragments?

Science

Volumn 273, Issue 5277, 1996, Pages 938-941

  Farinella, Paolo ^a   Davis, Donald R ^b  

^a UNIVERSITY OF PISA   (Italy)

^b PLANETARY SCIENCE INSTITUTE   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ARTICLE; ASTRONOMY; METEOROLOGICAL PHENOMENA; PRIORITY JOURNAL;

COLLISION EVENT; COMET; EDGEWORTH-KUIPER BELT OBJECT; FRAGMENTATION;

EID: 0029663178     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.273.5277.938     Document Type: Article

References (42)

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14. Both analytical theories and numerical integrations indicate that EKO eccentricities and sines of the inclination as high as 0.2 would result in long-term chaotic behavior for most bodies in nonresonant orbits [Z. Knežević, A. Milani, P. Farinella. Ch. Froeschlé, C. Froeschlé, Icarus 93, 316 (1991); A. Morbidelli, F. Thomas, M. Moons, ibid. 118, 322 (1996); M. J. Duncan, H. F. Levison, S. M. Budd Astron. J. 110, 3073 (1995)]. A significant fraction (≈40%) of known (large) EKOs are apparently trapped in stable resonant orbits, particularly the 2:3 mean motion resonance with Neptune. These bodies can have significant eccentricities (0.2 to 0.3) and inclinations (up to ≈25°); however, it is not clear that a significant percentage of all EKOs larger than 1 km in diameter will be similarly located on resonant orbits. Also, we disregard the possibility that EKOs may collisionally interact with a large population of high-eccentricity or high-inclination bodies with semimajor axes > 100 AU and perihelia near 40 AU, as predicted by some models for the formation of the Oort cloud [M. Duncan, T. Quinn, S, Tremaine, Astron. J. 94, 1330 (1987)], because there is currently no observational evidence for the existence of such a population.
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42. P. F. acknowledges financial support from the Italian Space Agency (ASI) and the Italian Ministry for University and Scientific Research (MURST). We are grateful to C. Chapman, H. Levison, F. Marzari, A. Milani, A. Stern, S. J. Weidenschilling, and D. E. Wheeler for useful discussions and comments. This is PSI contribution no. 334.