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Jupiter – friend or foe? I: The asteroids

Published online by Cambridge University Press:  23 July 2008

J. Horner  and
B.W. Jones
J. Horner
Affiliation:
Astronomy Group, Physics and Astronomy, The Open University, Milton Keynes MK7 6AA, UK e-mail: [email protected]
B.W. Jones
Affiliation:
Astronomy Group, Physics and Astronomy, The Open University, Milton Keynes MK7 6AA, UK e-mail: [email protected]
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Abstract

The asteroids are a major source of potential impactors on the Earth today. It has long been assumed that the giant planet Jupiter acts as a shield, significantly lowering the impact rate on the Earth from both cometary and asteroidal bodies. Such shielding, it is claimed, enabled the development and evolution of life in a collisional environment, which is not overly hostile. The reduced frequency of impacts, and of related mass extinctions, would have allowed life the time to thrive, where it would otherwise have been suppressed. However, in the past, little work has been carried out to examine the validity of this idea. In the first of several papers, we examine the degree to which the impact risk resulting from a population representative of the asteroids is enhanced or reduced by the presence of a giant planet, in an attempt to understand fully the impact regime under which life on Earth developed. Our results show that the situation is far less clear cut that has previously been assumed, that is, the presence of a giant planet can act to enhance the impact rate of asteroids on the Earth significantly.

Keywords

asteroidscometsminor planetsplanets and satellitesSolar SystemSolar System formation
Type
Research Article
Information
International Journal of Astrobiology , Volume 7 , Issue 3-4 , October 2008 , pp. 251 - 261
Copyright
Copyright © 2008 Cambridge University Press

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References

Bottke, W.F., Morbidelli, A., Jedicke, R., Petit, J., Levison, H.F., Michel, P. & Metcalfe, T.S. (2002). Debiased orbital and absolute magnitude distribution of the near-Earth objects. Icarus 156, 399–433.CrossRefGoogle Scholar
Chambers, J.E. (1999). A hybrid symplectic integrator that permits close encounters between massive bodies. Mon. Not. R. Astron. Soc. 304, 793–799.Google Scholar
Chapman, C.R. & Morrison, D. (1994). Impacts on the Earth by asteroids and comets: assessing the hazard. Nature 367, 33–40.Google Scholar
Davis, S.S. (2005). The surface density distribution in the solar nebula. ApJ 627, L153–L155.CrossRefGoogle Scholar
Gomes, R., Levison, H.F., Tsiganis, K. & Morbidelli, A. (2005). Origin of the cataclysmic Late Heavy Bombardment period of the terrestrial planets. Nature 435, 466–469.CrossRefGoogle ScholarPubMed
Greaves, J.S. (2006). Persistent hazardous environments around stars older than the Sun. Int. J. Astrobiology 5, 187–190.CrossRefGoogle Scholar
Horner, J. & Evans, N.W. (2006). The capture of Centaurs as Trojans. Mon. Not. R. Astron. Soc. 367(1), L20–L23.CrossRefGoogle Scholar
Jones, B.W. (2007). Discovering the Solar System. 2nd edn. John Wiley & Sons, Chichester.Google Scholar
Laakso, T., Rantala, J. & Kaasalainen, M. (2006). Gravitational scattering by giant planets. Astron. Astrophys. 456, 373–378.Google Scholar
Morbidelli, A., Bottke, W.F., Froeschlé, Ch. & Michel, P. (2002). Origin and Evolution of Near-Earth Objects. Asteroids III. University of Arizona Press, Tucson, AZ, pp. 409–422.Google Scholar
Morris, S.C. (1998). The evolution of diversity in ancient ecosystems: a review. Philos. Trans. R. Soc. Lond., B, Biol. Sci. 353, 327–345.Google Scholar
Murray, C.D. & Dermott, S.F. (1999). Solar System Dynamics. Cambridge University Press, Cambridge, Chapters 8 and 9.Google Scholar
Oort, J.H. (1950). The structure of the cloud of comets surrounding the Solar System, and a hypothesis concerning its origin. Bull. Astron. Inst. Ned. 11(408), 91–110.Google Scholar
Ward, W.R. (2005). Early clearing of the asteroid belt. Abstracts of the 36th Lunar and Planetary Science. Abstract 1491, 2 pp.Google Scholar
Ward, W.R. & Brownlee, D. (2000). Rare Earth: Why Complex Life is Uncommon in the Universe. Copernicus, pp. 238–239.Google Scholar
Wetherill, G.W. (1991). Occurrence of Earth-like bodies in planetary systems. Science 253, 535–538.CrossRefGoogle ScholarPubMed
Wetherill, G.W. (1994). Possible consequences of absence of Jupiters in planetary systems. Astrophys. Space Sci. 212, 23–32.Google Scholar