Abstract
The geological and biological sciences have gradually dispensed with the nineteenth-century concept of substantive uniformitarianism - or gradualism - whereby the physical and biological features of our planet are assumed to have been brought about by the long-term accumulation of small changes. The catastrophist alternative sees the changes as being wrought largely by discrete, exceptional events; one such type of event is an impact by a substantial asteroid or comet. It is argued here that scientists working on small solar system bodies generally still labour under a form of this gradualism, in that a conventional starting point is to presume a steady-state, and what is seen now is assumed to be diagnostic of the long-term average conditions. This is here termed NEO-uniformitarianism, the NEO referring to Near-Earth Objects. It is maintained herein that this area of science needs to revise its philosophical basis by allowing catastrophist principles to be entertained; that is, the presumption of a steady-state needs to be rejected until such time as evidence to support it is revealed. It is argued that the weight of evidence favours the contrary. For example, evidence is outlined for (a) Variations in the terrestrial cratering rate, disallowing any equating of the crater record with the presently-observed large impactor population; (b) The presence of significant NEO complexes which may be due to giant comet disintegrations within the last 20 kyr, hence solving the problem of the supply of short-period comets; (c) A misbalance between the present supply of meteoroids, there being too many to be supplied by presently-observed comets and also a surplus above the population needed to maintain the interplanetary dust complex; and (d) A substantial variation in the interplanetary dust flux in the past 20 kyr, as might be expected from (b and c).
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Alvarez, W., Hansen, T., Hut, P., Kauffman, E.G., & Shoemaker, E.M. (1989), Uniformitarianism and the response of Earth scientists to the theory of impact crises. Catastrophes and Evolution: Astronomical Foundations, ed Clube, S.V.M., Cambridge University Press, Cambridge, U.K., pp. 13–24.
Asher, D.J., Bailey, M.E., Hahn, G., & Steel, D.I. (1994a). Asteroid 5335 Damocles and its implication for cometary dynamics. Mon. Not. Roy. Astron. Soc., 267, 26–42.
Asher, D.J., & Clube, S.V.M. (1993). An extraterrestrial influence during the current glacial- interglacial. Ql. J. Roy. Astron. Soc., 34, 481–511.
Asher, D.J., Clube, S.V.M., Napier, W.M., & Steel, D.I. (1994b). Coherent catastrophism. Vistas Astron., 38, 1–27.
Asher, D.J., & Steel, D.I. (1993). Orbital evolution of the large outer solar system object 5145 Pholus. Mon. Not. Roy. Astron. Soc., 263, 179–190.
Babadzhanov, P.B., & Obrubov, Yu.V. (1992). Evolution of short-period meteoroid streams. Cel. Mech. Dyn. Astron.,54, 111–127.
Babadzhanov, P.B., Obrubov, Yu.V., & Makhmudov, N. (1990). Meteor streams of Comet Encke. Sol. Sys. Res., 24, 12–19.
Bailey, M.E., Clube, S.V.M., Hahn, G., Napier, W.M., & Valsecchi, G.B. (1994). Hazards due to giant comets: Climate and short-term catastrophism. The Hazard due to Comets and Asteroids, ed Gehrels, T., University of Arizona Press, Tucson, pp. 479–533.
Bradley, J.P., Brownlee, D.E., & Fraundorf, P. (1984). Discovery of nuclear tracks in interplanetary dust. Science, 226, 1432–1434.
Clube, S.V.M., & Napier, W.M. (1984). The microstructure of terrestrial catastrophism. Mon. Not. Roy. Astron. Soc., 211, 953–968.
Clube, S.V.M., & Napier, W.M. (1986). Giant comets and the galaxy: implications of the terrestrial record. The Galaxy and the Solar System, eds Smoluchowski, R., Bahcall, J.N., & Matthews, M.S., University of Arizona Press, Tucson, pp. 260–285.
Clube, S.V.M., & Napier, W.M. (1987). The cometary breakup hypothesis re-examined: a reply. Mon. Not. Roy. Astron. Soc., 225, 55P-58P.
Farinella, P., Froeschlé, Ch., Froeschlé, Cl., Gonczi, R., Hahn, G., Morbidelli, A., & Valsecchi, G.B. (1994). Asteroids falling into the Sun. Nature, 371, 314–317.
Goswami, J.N. (1991). Solar flare heavy-ion tracks in extraterrestrial objects. The Sun in Time, eds Sonett, C.P., Giampapa, M.S., & Matthews, M.S., University of Arizona Press, Tucson, pp. 426–444.
Gould, S.J. (1965). Is uniformitarianism necessary? Amer. J. Sci., 263, 223–228.
Gould, S.J., & Eldredge, N. (1993). Punctuated equilibrium comes of age. Nature, 366, 223–227.
Grieve, R.A.F. (1982). The record of impact on Earth: Implications for a major Cretaceous/ Tertiary impact event. Geol. Soc. Amer., Spec. Pap., 190, 25–37.
Grün, E., Zook, H.A., Fechtig, H., & Giese, R.H. (1985). Collisional balance of the meteoritic complex. Icarus, 62, 244–272.
Hahn, G., & Bailey, M.E. (1990). Rapid dynamical evolution of giant comet Chiron. Nature, 348, 132–136.
Hartung, J.B., & Storzer, D. (1974). Lunar microcraters and their solar flare track record. Proc. Fifth Lunar Sci. Conf., Vol. 3, 2527–2541.
Hughes, D.W. (1990). The mass of meteor streams. Mon. Not. Roy. Astron. Soc., 240, 73–79.
Klačka, J. (1995). The Taurid complex of asteroids. Astron. Astrophys., in press.
Kresák, ľ. (1980). “Sources of interplanetary dust.” IAU Symp. 90, Solid Particles in the Solar System, eds Halliday, I., & McIntosh, B.A., Reidel, Dordrecht, pp. 211–222.
Kresák, ľ., & štohl, J. (1990). Genetic relationships between comets, asteroids and meteors. Asteroids, Comets, Meteors III, eds Lagerkvist, C.-I., Rickman, H., Lindblad, B.A., & Lindgren, M., University of Uppsala, Sweden, pp. 379–388.
La Violette, P.A. (1987). The cometary breakup hypothesis re-examined. Mon. Not. Roy. Astron. Soc., 224, 945–951.
Leinert, C., Röser, S., & Buitrago, J. (1983). How to maintain the spatial distribution of interplanetary dust. Astron. Astrophys., 118, 345–357.
Marvin, U.B. (1990). Impact and its revolutionary implications for geology. Geol. Soc. Amer., Spec. Pap., 247, 147–154.
Menichella, M., Paolicchi, P., & Farinella, P. (1995). “The main belt as a source of near-Earth asteroids.” These proceedings.
Napier, W.M. (1993). Earth-crossing asteroid grou\'ps. Meteoroids and their parent bodies, eds štohl, J., & Williams, I.P., Slovak Academy of Sciences, Bratislava, pp. 123–126.
Nininger, H.H. (1942). Cataclysm and Evolution. Pop. Astron., 50, 270–272.
Olsson-Steel, D. (1986). The origin of the sporadic meteoroid component. Mon. Not. Roy. Astron. Soc., 219, 47–73.
Pittich, E.M., & Rickman, H. (1994). Cometary splitting - a source for the Jupiter family? Astron. Astrophys., 281, 579–587.
Rampino, M.R., & Caldeira, K. (1993). Major episodes of geologic change: correlations, time structure and possible causes. Earth Planet. Sci. Lett., 114, 215–227.
Raup, D.M. (1991). Extinction: Bad Genes or Bad Luck? Norton, New York.
Reach, W.T. (1992). On the origin of interplanetary dust within recorded history. Meteoritics, 27, 353–360.
Sekanina, Z. (1982). The problem of split comets in review. Comets, ed Wilkening, L.L., University of Arizona Press, Tucson, pp. 251–287.
Shea, J.H. (1982). Twelve fallacies of uniformitarianism. Geology, 10, 455–460.
Shoemaker, E.M. (1983). Asteroid and Comet Bombardment of the Earth. Ann. Rev. Earth Planet. Sci., 11, 464–494.
Steel, D.I. (1991). Our asteroid-pelted planet. Nature, 354, 265–267.
Steel, D.I., & Asher, D.J. (1994). P/Helfenzrieder (1766 II) and the Hephaistos group of Earthcrossing asteroids. The Observatory, 114, 223–226.
Steel, D.I., Asher, D.J., & Clube, S.V.M. (1991). The structure and evolution of the Taurid Complex. Mon. Not. Roy. Astron. Soc., 251, 632–648.
Steel, D.I., & Elford, W.G. (1986). Collisions in the Solar System - III. Meteoroid survival times. Mon. Not. Roy. Astron. Soc., 218, 185–199.
Stern, S.A. (1995). Chiron illuminated. Nature, 373, 23–24.
štohl, J. (1980). “On time-dependent models of the meteoric background complex.” Solid Particles in the Solar System, IAU Symp. 90, eds Halliday, I., & McIntosh, B.A., Reidel, Dordrecht, pp. 141–144.
štohl, J. (1986a). The distribution of sporadic meteor radiants and orbits. Asteroids, Comets, Meteors II, eds Lagerkvist, C.-I., Lindblad, B.A., Lundstedt, H., & Rickman, H., University of Uppsala, Sweden, pp. 565–574.
štohl, J. (1986b). “On meteor contribution by short-period comets.” Proc. 20th ESLAB Symp. on the Exploration of Halley's Comet, ESA SP-250, Vol. II, 225–228.
štohl, J., & Porubčan, V. (1990). Structure of the Taurid meteor complex. Asteroids, Comets, Meteors III, eds Lagerkvist, C.-I., Rickman, H., Lindblad, B.A., & Lindgren, M., University of Uppsala, Sweden, pp. 571–574.
štohl, J., & Porubčan, V. (1992). Dynamical aspects of the Taurid meteor complex. Chaos, Resonance and Collective Dynamical Phenomena in the Solar System, IAU Symp. 152, ed Ferraz-Mello, S., Kluwer, Dordrecht, pp. 315–324.
Stothers, R.B. (1992). Impacts and tectonism in Earth and Moon history of the past 3800 million years. Earth, Moon & Planets, 58, 145–152.
Urey, H.C. (1973). Cometary collisions and geological periods. Nature, 242, 32–33.
Wetherill, G.W. (1991). End products of cometary evolution: cometary origin of Earth-crossing bodies of asteroidal appearance. Comets in the Post-Halley Era, eds Newburn, R.L. Jr., Neugebauer, M., & Rahe, J., Kluwer, Dordrecht, pp. 537–556.
Whipple, F.L. (1967). On maintaining the meteoritic complex. The Zodiacal Light and the Interplanetary Medium, NASA SP-150, ed Weinberg, J.L., NASA, Washington, D.C., pp. 409–426.
Whipple, F.L., & Hamid, S.E. (1952). On the origin of the Taurid meteor streams. Helwan Obs. Bull., 41, 1–30.
Yabushita, S. (1992). Periodicity in the crater formation rate and implications for astronomical modelling. Cel. Mech. Dyn. Astron., 54, 161–178.
Zook, H.A. (1978). Temporal and spatial variations of the interplanetary dust flux. Space Research, XVIII, 411–422.
Zook, H.A. (1980). On lunar evidence for a possible large increase in solar flare activity ~2×104 years ago. Proc. Conf. Ancient Sun, eds Pepin, R.O., Eddy, J.A., & Merrill, R., Pergamon Press, Oxford, pp. 245–266.
Zook, H.A., Hartung, J.B., & Storzer, D. (1977). Solar flare activity: evidence for large-scale changes in the past. Icarus, 32, 106–126.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Steel, D.I. The limitations of NEO-uniformitarianism. Earth Moon Planet 72, 279–292 (1996). https://doi.org/10.1007/BF00117530
Issue Date:
DOI: https://doi.org/10.1007/BF00117530