Simulation of rocket-borne particle measurements in the mesosphere

Nanometer-sized meteoric smoke particles and ice condensates are thought to influence the chemistry in the 80-120 km altitude region and to play an im portant role in the evolution of Polar Mesosphere Summer Echoes and Noctluc ent Clouds. In this paper we show that aerodynamic perturbations introduced by a rocket payload complicate the analysis of dust measurements in this r egion. We analyze the flow of particles by applying a combined numerical si mulation of flight aerodynamics and particle evolution. We show that for ty pical velocities of 500 - 1000 ms(-1), the detection efficiency drops below 50 % for smoke particles with radii 0.8-1.4 nm and for ice clusters with r adii 2-5 nm, depending on the rocket's angle of attack. The particles are e xposed to heating in the shock region, resulting in significant mass loss f or ice condensates due to sublimation. Our simulations indicate that a subs tantial fraction of the expected nm sized meteoric smoke particles could be detected with refined instrumentation.