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Progress towards the vindication of panspermia


Theories of panspermia are rapidly coming into vogue, with the possibility of the transfer of viable bacterial cells from one planetary abode to another being generally accepted as inevitable. The panspermia models of Hoyle and Wickramasinghe require the transfer of viable bacterial cells from interstellar dust to comets and back into interplanetary and interstellar space. In such a cycle a viable fraction of as little as 10-18 at the inception of a newly formed comet/planet system suffices for cometary panspermia to dominate over competing processes for the origin and transfer of life. The well-attested survival attributes of microbes under extreme conditions, which have recently been discovered, gives credence to the panspermia hypothesis. The prediction of the theory that comets bring microbes onto the Earth at the present time is testable if aseptic collections of stratospheric air above the tropopause can be obtained. We describe a recent collection of this kind and report microbiological analysis that shows the existence of viable cells at 41 km, falling to Earth at the rate of a few tonnes per day over the entire globe. Some of these cells have been cultured in the laboratory and found to include microorganisms that are not too different from related species on the Earth. This is in fact what the Hoyle-Wickramasinghe theory predicts. The weight of evidence goes against the more conservative explanation that organisms are being lofted to the high atmosphere from the ground.

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  • Allen, C.W.: 1967, Astrophysical Quantities, London Athlone Press.

  • Bigg, E.K.: 1983, in: C. Wickramasinghe (ed.), Fundamental Studies and the Future of Science, University College Cardiff Press, pp. 38‐51.

  • Burch, C.W.: 1967, Symp. Soc. Gen. Microbiol. 17, 345‐373.

    Google Scholar 

  • Cano, R.J. and Borucki, M.: 1995, Science 268, 1060‐1064.

    ADS  Google Scholar 

  • Clemett, S.J., Maechling, C.R., Zare, R.N., Swan, P.D. and Walker, R.M.: 1993, Science 263, 721‐725.

    ADS  Google Scholar 

  • Colbeck, I.: 1998, in: I. Colbeck (ed.), Physical and Chemical Properties of Aerosols, Blackie, London.

    Google Scholar 

  • Cowan, D. and Grady, M.: 2000, Microbiology Today 27, 174‐177.

    Google Scholar 

  • Harris, M.J., Wickramasinghe, N.C., Lloyd, D., Narlikar, J.V., Rajaratnam, P., Turner, M.P., Al-Mufti, S., Wallis, M.K., Ramadurai, S. and Hoyle, F.: 2001, The detection of living cells in stratospheric samples, Proc SPIE Conf. 4495, in press.

  • Hoyle, F.: 1981, The relation of biology to astronomy, University College Cardiff Press.

  • Hoyle, F. and Wickramasinghe, N.C.: 1981, in: C. Ponnamperuma (ed.), Comets and the Origin of Life, D. Reidel, pp. 227‐239.

  • Hoyle, F. and Wickramasinghe, N.C.: 1985, Living Comets, University College, Cardiff Press.

  • Hoyle, F. and Wickramasinghe, N.C.: 2000, Astronomical Origins of Life: Steps towards Panspermia, Kluwer Academic Publishers.

  • Hoyle, F., Wickramasinghe, N.C. and Al-Mufti, S.: 1984, Astrophys. Space Sci. 98, 234.

    Article  Google Scholar 

  • Jayaweera, K. and Flanagan, P.: 1982, Geophys. Res. Lett. 9, 94‐97.

    ADS  Google Scholar 

  • Kasten, F.: 1968, J. Appl. Meteorol. 7, 944‐947.

    Article  ADS  Google Scholar 

  • Lal, S., Archarya, Y.B., Patra, P.K., Rajaratnam, P., Subbarya, B.H. and Venkataramani, S.: 1996, Ind. J. Radio Space Phys. 25, 1‐7.

    Google Scholar 

  • McCarthy, M.: 2001, Lancet 358, 478.

    Article  Google Scholar 

  • Narlikar, J.V., Ramadurai, S., Bhargava, Pushpa, Damle, S.V., Wickramasinghe, N.C., Lloyd, D., Hoyle, F. and Wallis, D.H.: 1998, Proc. SPIE Conf. 3441, 301‐305.

    ADS  Google Scholar 

  • Vreeland, R.H., Rosenzweig, W.D. and Powers, D.: 2000, Nature 407, 897‐900.

    Article  ADS  Google Scholar 

  • Wainwright, M., Wickramasinghe, N.C., Narlikar, J.V. and Rajaratnam, P.: 2002, submitted to Microbiology.

  • Wickramasinghe, N.C.: 1974, Nature 252, 462.

    Article  ADS  Google Scholar 

  • Wickramasinghe, N.C. and Vanysek, V.: 1975, Astrophys. Space Sci. 33, L19.

    Google Scholar 

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Wickramasinghe, N., Wainwright, M., Narlikar, J. et al. Progress towards the vindication of panspermia. Astrophysics and Space Science 283, 403–413 (2003).

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  • Solar System
  • Electron Beam Weld
  • Interstellar Dust
  • Oort Cloud
  • Interstellar Space