Examining the short and long term effects of the Chicxulub impact is critical for understanding how life developed on Earth. While the aftermath of the initial impact would have produced harmful levels of radiation sufficient for eradicating a large portion of terrestrial life, this process does not explain the concurrent marine extinction. Following the primary impact, a large quantity of smaller spherules would de-orbit and re-enter the earths atmosphere, dispersed nearly uniformly across the planet. This secondary wave of debris would re-enter at high velocities, altering the chemical composition of the atmosphere. Furthermore, the combined surface area for the spherules would be much larger than for the original asteroid, resulting in considerably more potential reactions. For this reason, a new method was developed for predicting the total amount of toxic species produced by the spherule re-entry phase of the Chicxulub event. Using non-equilibrium properties obtained from direct simulation Monte Carlo (DSMC) methods coupled with spherule trajectory integration, the most likely cause of the observed marine extinction was determined.


Copyright (2012) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in (D. Parkos*, M. Kulakhmetov*, B. Johnson, H. J. Melosh, and A. Alexeenko, “Climatic effects of the Chicxulub impact ejecta”, Proceedings of 28th International Symposium on Rarefied Gas Dynamics, 9–13 July 2012, Zaragoza, Spain, AIP Conf. Proc. 1501, pp. 1557-1565.) and may be found at http://dx.doi.org/10.1063/1.4769724. The following article has been submitted to/accepted by [American Institute of Physics]. After it is published, it will be found at (http://dx.doi.org/10.1063/1.4769724). Copyright (2012) D. Parkos*, M. Kulakhmetov*, B. Johnson, H. J. Melosh, and A. Alexeenko. This article is distributed under a Creative Commons Attribution 3.0 Unported License.

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