On the density of the dust halo around Mars

The escape flux of dust grains from Phobos and Deimos caused by the interplanetary micrometeoroid flux in the mass range 10 exp -18 g to 100 g is examined. The lifetime of ejected dust grains around Mars is investigated considering electromagnetic and light pressure perturbations, collisions, and the Poynting-Robertson effect as possible loss mechanisms. The average number densities of accumulated particles in the different regions of the Martian environment are estimated. It is concluded that particles with sizes less than 0.5 micron and between 7 and 50 microns are the most abundant in the Martian dust environment.