Cratering and Blowing Soil by Rocket Engines During Lunar Landings

This paper is a summary compilation of work accomplished over the past decade at NASA’s Kennedy Space Center to understand the interactions between rocket exhaust gases and the soil of the Moon or Mars. This research is applied to a case study of the Apollo 12 landing, in which the blowing soil peppered the nearby Surveyor III spacecraft producing measurable surface damage, and to the Apollo 15 landing, in which the Lunar Module tilted backwards after landing in a crater that was obscured from sight by the blowing dust. The modeling coupled with empirical observations is generally adequate to predict the order of magnitude of effects in future lunar missions and to formulate a rough concept for mitigating the spray around a lunar base. However, there are many significant gaps in our understanding of the physics and more effort is needed to understand the problem of blowing soil so that specific technologies can be developed to support the lunar outpost