Effect of an impact-generated gas cloud on the acceleration of solid ejecta

Abstract

A hypothesis that vaporization of a large amount of volatiles such as H2O and CO2 in the Martian surface by the impact of a large object could have accelerated solid ejecta to earth is examined. A hydrodynamic model is used to approximate a hemispherical gas cloud expanding into an atmosphere and entraining solid ejecta. Account is taken of the target material, the impactor materials, mass vaporized, impact velocity, drag coefficient, and crater sizes. A Martian crater larger than 30 km diam is found to be a necessary remnant of any impact that could have produced the shergottites, nakhlites and Chassigny meteorites which have been found on earth and possess similarities to analyzed Martian rocks.