Implications of ice morphology for comet formation

Collings, M. P. and Dever, J. W. and McCoustra, M. R. S. and Fraser, H. J.; Engvold, O, ed. (2005) Implications of ice morphology for comet formation. In: Highlights of astronomy. IAU Symposia, 13 . ASTRONOMICAL SOC PACIFIC, AUS, pp. 491-494. ISBN 1583811893

Full text not available in this repository.Request a copy

Abstract

Laboratory surface science under ultra-high vacuum (UHV) conditions allows us to simulate the growth of ices in astrophysical environments. Using the techniques of temperature programmed desorption (TPD), reflection-absorption infrared spectroscopy (RAIRS) and micro-balance methods, we have studied binary ice systems consisting of water (H2O) and variety of other species including carbon monoxide (CO), at astrophysically relevant conditions of temperature and pressure. We present results that demonstrate that the morphology of water ice has an important influence on the behavior of such systems, by allowing processes such as diffusion and trapping that can not be understood through a knowledge of the binding energies of the species alone. Through an understanding of the implications of water ice morphology on the behavior of ice mixtures in the interstellar environment, additional constraints can be placed on the thermodynamic conditions and ice compositions during comet formation.