THE RELATIVE EFFICIENCY OF AEROCAPTURE FOR INTERPLANETARY DUST BY THEPLANETS

Numerical techniques have been applied to calculating the trajectories of interplanetary particles approaching the Earth, Venus and Saturn u nder the influence of gravitational and atmospheric drag forces. Parti cle capture cross-sections and orbital evolution and lifetimes have be en calculated. In addition, the peak temperatures and pressures experi enced by particles during aerobraking have been calculated in order to assess the relative importance of aerocapture and aerofragmentation c apture. Results suggest that the differing masses, atmospheric profile s and solar distances of the planets result in significantly different populations of captured orbital material. For the Earth, the populati on of natural orbital material will show a steeper mass distribution t han does the interplanetary population due to the preferential capture of smaller particles. Venus will have only a small population of orbi tal particles as its small atmospheric scale height results in very sm all capture probabilities. Saturn will have a significant population o f captured material, but with a broadly interplanetary mass distributi on due to the small mass dependence of the capture probability.