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The origin of life in comets

Published online by Cambridge University Press:  19 December 2007

W.M. Napier
Affiliation:
Cardiff Centre for Astrobiology, Cardiff University, 2 North Road, Cardiff CF10 3DY, UK e-mail: napierwm@cardiff.ac.uk
J.T. Wickramasinghe
Affiliation:
Cardiff Centre for Astrobiology, Cardiff University, 2 North Road, Cardiff CF10 3DY, UK e-mail: napierwm@cardiff.ac.uk
N.C. Wickramasinghe
Affiliation:
Cardiff Centre for Astrobiology, Cardiff University, 2 North Road, Cardiff CF10 3DY, UK e-mail: napierwm@cardiff.ac.uk

Abstract

Mechanisms of interstellar panspermia have recently been identified whereby life, wherever it has originated, will disperse throughout the habitable zone of the Galaxy within a few billion years. This re-opens the question of where life originated. The interiors of comets, during their aqueous phase, seem to provide environments no less favourable for the origin of life than that of the early Earth. Their combined mass throughout the Galaxy overwhelms that of suitable terrestrial environments by about 20 powers of ten, while the lifetimes of friendly prebiotic environments within them exceeds that of localized terrestrial regions by another four or five powers of ten. We propose that the totality of comets around G-dwarf Sun-like stars offers an incomparably more probable setting for the origin of life than any that was available on the early Earth.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2007

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References

A'Hearn, M.F. et al. (2005). Whence comets? Science 314, 17081709.CrossRefGoogle Scholar
Bailey, M.E., Clube, S.V.M. & Napier, W.M. (1990). The Origin of Comets. Pergamon, Oxford.Google Scholar
Beichman, C.A. et al. (2005). An excess due to small grains around the nearby K0 V Star HD 69830: asteroid or cometary debris? Astrophys. J. 626, 10611069.CrossRefGoogle Scholar
Cairns-Smith, A.G. (1966). The origin of life and the nature of the primitive gene. J. Theor. Biol. 10, 53.CrossRefGoogle ScholarPubMed
Cairns-Smith, A.G. & Hartman, H. (eds) (1986). Clay Minerals and the Origin of Life. Cambridge University Press, Cambridge.Google Scholar
Carny, O. & Gazit, E. (2005). A model for the role of short self-assembled peptides in the very early stages of the origin of life. FASEB Journal 19, 10511055.CrossRefGoogle Scholar
Cataldo, F. (2007). Radiation-induced racemization and amplification of chirality: implications for comets and meteorites. Int. J. Astrobiol. 6, 110.CrossRefGoogle Scholar
Cha, J.N. et al. (2000). Biomimetic synthesis of ordered silica structures mediated by block copolypeptides. Nature 403, 289292.CrossRefGoogle ScholarPubMed
Gilbert, W. (1986). Origin of life: the RNA world. Nature 319, 618.CrossRefGoogle Scholar
Grady, C.A. et al. (1997). The star-grazing extrasolar comets in the HD 100546 system. Astrophys. J. 483, 449456.CrossRefGoogle Scholar
Hazen, R.M. (2005). Genesis. Joseph Henry Press, Washington, DC.Google Scholar
Hecky, R.E. et al. (1973). The amino acid and sugar composition of diatom cell-walls. Marine Biol. 19, 323331.CrossRefGoogle Scholar
Hoyle, F. & Wickramasinghe, N.C. (1999). The universe and life: implications from the weak anthropic principle. Astrophys. Space Sci. 268, 89102.CrossRefGoogle Scholar
Jura, M. (2005). Direct detection of extra-solar comets is possible. Astron J. 130, 12611266.CrossRefGoogle Scholar
Lin, L.F. et al. (2006). Long-term sustainability of a high-energy, low-diversity crustal biome. Science 314, 479482.CrossRefGoogle ScholarPubMed
Lisse, C.M. et al. (2006). Spitzer spectral observations of the Deep Impact ejecta. Science 313, 635640.CrossRefGoogle ScholarPubMed
Melnick, G.J. et al. (2001). Discovery of water vapour around IRC+10216 as evidence for comets orbiting another star. Nature 412, 160163.CrossRefGoogle ScholarPubMed
Morbidelli, A. et al. (2000). Source regions and timescales for the delivery of water to Earth. Meteor. Planet. Sci. 35, 13091320.CrossRefGoogle Scholar
Napier, W.M. (2004). A mechanism for interstellar panspermia. Mon. Not. R. Astron. Soc. 348, 4651.CrossRefGoogle Scholar
Napier, W.M. (2007). Pollination of exoplanets by nebulae. Int. J. Astrobiol., in press.CrossRefGoogle Scholar
Raymond, S.N., Quinn, T. & Lunine, J.L. (2004). Making other Earths: dynamical simulations of terrestrial planet formation and water delivery. Icarus 168, 117.CrossRefGoogle Scholar
Sandford, S.A. et al. (2006). Organics captured from comet 81P/Wild 2 by the Stardust spacecraft. Science 314, 17201724.CrossRefGoogle ScholarPubMed
Szostak, J.W., Bartel, D.P. & Luisi, P.L. (2001). Synthesizing life. Nature 409, 387390.CrossRefGoogle ScholarPubMed
Wallis, M. & Wickramasinghe, N.C. (2004). Interstellar transfer of planetary microbiota. Mon. Not. R. Astron. Soc. 348, 52.CrossRefGoogle Scholar
Wickramasinghe, J.T. (2007). The role of comets in panspermia. PhD Thesis, Cardiff University.Google Scholar
Wickramasinghe, J.T., Wickramasinghe, N.C. & Wallis, M. (2008). Liquid water and organics in comets: implications for exobiology. Int. J. Astrobiol., in press.Google Scholar
Woese, C. (1968). The Genetic Code. Harper and Row, New York.Google ScholarPubMed
Ziegler, K. & Longstaffer, F.J. (2000). Clay Clay Minerals 48, 474493.CrossRefGoogle Scholar