Advertisement

The Nature of Comets

  • David W. Hughes
Part of the Springer Praxis Books book series (PRAXIS)

Abstract

Our knowledge of comets has advanced hugely since the 1986 apparition of Comet Halley provided the spur to spacecraft investigation. But our understanding is still very much ‘skin deep’. The mass of the nucleus, the density of the nucleus and its internal structure and strength are poorly understood. Whether the physical and chemical properties vary from place to place in a specific cometary nucleus, or from comet to comet is still a mater of conjecture. Recent low-resolution images of nuclei surfaces are improving our understanding, but the real breakthrough will probably have to wait until a probe lands on a cometary surface in 2014, and until future probes return material to Earth some decades later. In this chapter we summarise our knowledge of the physical properties and chemical composition of the cometary nucleus paying special attention to the four comets that have had their nuclei imaged by spacecraft, these being comets Halley, Borrelly, Wild-2 and Tempel-1. Special attention is paid to the rate at which the cometary nucleus decays and the effect this has on cometary activity and the thickness of the allencompassing surface dust layer. The results of recent cometary space mission are summarised, special attention being paid to the Deep Impact mission to comet Tempel-1.

Keywords

Solar System Dust Particle Heliocentric Distance Cometary Nucleus Dust Layer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. A’Hearn, M. F. at al., 2005. Science 310, 257.CrossRefGoogle Scholar
  2. Anders E. and Ebihara M., 1982. Geochim. Cosmochim Acta 46, 2363.CrossRefADSGoogle Scholar
  3. Bame, S. J., et al., 1986. Science 232, 356.ADSCrossRefGoogle Scholar
  4. Belton, M.J.S., Meech, K.J., A’Hearn, M.F., Groussin, O., McFadden, L., Lisse, C., Fernández, Y.R., Pittichová, J., Hseih, H., Kissel, J., Klassen, K., Lamy, P., Prialnik, D., Sunshine, J., Thomas, P., Toth, I., 2005. Space Science Reviews 117, 137.CrossRefADSGoogle Scholar
  5. Boice, D.C. and Huebner W.F., 1999. Physics and chemistry of comets. In Encyclopaedia of the Solar System, eds. P.R. Weissman, L.-A. McFadden and T.V. Johnson, Academic Press, San Diego, pp 519–536.Google Scholar
  6. Brownlee, D. E., Horz, F., Newburn, R. L., Zolensky, M., Duxbury, T. C., Sandford, S., Sekanina, Z., Tsou, P., Hanner, M. S., Clark, B. C., Green, S. F., Kissel, J., 2004. Science 304, 1764.CrossRefADSGoogle Scholar
  7. Crifo, J. F., and Rodionov, A. V., 1997. Icarus 127, 319.CrossRefADSGoogle Scholar
  8. Crovisier, J., and Encrenaz, T., 2000. Comet Science, Cambridge University Press, p. 98.Google Scholar
  9. Dohnanyi, J. S., 1978. In Cosmic Dust, ed. J.A.M. McDonnell, John Wiley and Sons, p. 559.Google Scholar
  10. Feldman, P.D., Festou, M.C., A’Hearn, M. F., Arpigny, C., Butterworth, P. S., Cosmovici, C. B., Danks, A. C., Gilmozzi, R., Jackson, W. M., McFadden, L. A., Patriachi, P., Schleicher, D. G., Tozzi, G. P., Wallis, M. K., Weaver, H. A., Woods, T. N., 1987. Astron. and Astrophys. 187, 325.ADSGoogle Scholar
  11. Grard, R., Gombosi, T. I., and Sagdeev, R. Z., 1986. In ESA SP-1066, Space Missions to Halley’s Comet, eds. R. Reinhard and B. Battrick, ESTEC, Noordwijk, Netherlands, p. 49.Google Scholar
  12. Groussin, O., and Lamy, P., 2003. Astron. and Astrophys. 412, 879.CrossRefADSGoogle Scholar
  13. Harker, D.E., et al., 2005. Science 310, 278.CrossRefADSGoogle Scholar
  14. Hirao, K., 1986. In ESA SP-1066, Space Missions to Halley’s Comet, eds. R. Reinhard and B. Battrick, ESTEC, Noordwijk, Netherlands, p. 71.Google Scholar
  15. Huebner, W.F., Boice, D.C., 1999. In Encyclopaedia of the Solar System, eds. P.R. Weissman, L-A. McFadden and T.V. Johnson, Academic Press, San Diego, pp. 519–536.Google Scholar
  16. Hughes, D.W., 1985. Mon. Not. R. Astr. Soc. 213, 103.ADSGoogle Scholar
  17. Hughes, D.W., 1988. Mon. Not. R. Astr. Soc. 234, 173.ADSGoogle Scholar
  18. Hughes, D.W., 1991. In Comets in the Post-Halley Era, Vol. 2, eds. R.L. Newburn, Jr., M. Neugebauer and J. Rahe, Kluwer Academic Publishers, Dordrecht, p. 825.Google Scholar
  19. Hughes, D.W., 2000. Mon. Not. R. Astr. Soc. 316, 642.CrossRefADSGoogle Scholar
  20. Hughes, D.W., 2001. J. Brit Interplanetary Soc. 54, 169.Google Scholar
  21. Hughes, D.W., and McBride, N., 1992. J. Brit. Astron. Assoc. 102, 5.Google Scholar
  22. Levison, H.F., and Duncan, M.J., 1997. Icarus 127, 13.CrossRefADSGoogle Scholar
  23. Lyttleton, R.A., 1953. The Comets, Cambridge University Press. Meech, K.J. et al., 2005. Science 310, 265.Google Scholar
  24. Morrison, D., and Owen T., 1988. The Planetary System, Addison Wesley, p. 143.Google Scholar
  25. Mumma, M.J., et al.. 2005, Science 310, 270.CrossRefADSGoogle Scholar
  26. Rayman, M, D., 2003. Space Technology 23, 185.Google Scholar
  27. Reinhard, R., 1986. In ESA SP-1066, Space Missions to Halley’s Comet, eds. R. Reinhard and B. Battrick, ESTEC, Noordwijk, Netherlands, p. 25.Google Scholar
  28. Rickman, H., Kamél L., Festou, M.C., Froeschlé, C., 1987. In ESA SP-278, Diversity and Similarity of Comets, eds. E.J. Rolfe and B. Battrick, ESTEC, Noordwijk, p. 471.Google Scholar
  29. Soderblom, L. A., et al., 2002. Science 296, 1087.CrossRefADSGoogle Scholar
  30. Sugita, et al., 2005. Science 310, 274.CrossRefADSGoogle Scholar
  31. Verdant, M. and Schwehm, G.H., 1998. ESA Bulletin 93, 39.ADSGoogle Scholar
  32. Whipple, F.L., 1950a. Astrophysical Journal 111, 375 and 113, 464.CrossRefADSGoogle Scholar
  33. Whipple, F.L., 1972. Cometary nuclei models. In NASA-CR-129110, Comets: Scientific Data and Missions, eds. G.P. Kuiper and E. Roemer, NASA, Washington D.C, pp. 12–15.Google Scholar

Copyright information

© Praxis Publishing Ltd 2006

Authors and Affiliations

  • David W. Hughes
    • 1
  1. 1.Department of Physics and AstronomyUniversity of SheffieldSheffieldUK

Personalised recommendations