Formation and Properties of the Martian Dust Aerosol

Introduction: Mars is a test bed for the study of dust aerosols since, lacking the active circulation of water through the atmosphere (as seen on earth), dust transport has become the dominant process for both atmospheric contamination and the dynamics of the surface. Presently the transport of fine, dust-like granular material is the most active process affecting the Martian surface. The suspension of this dust in the Martian atmosphere is also a major factor affecting the planets climate. Despite the widespread observation of other wind induced erosion features on Mars, for example sand forms, generally sand appears to be presently transported only at a at a low rate. The physical processes at work here are being actively studied both at the Martian surface and in laboratory simulators. A discussion will be made of the current level of understanding of mineral grain transport on Mars and some of the technology involved in this research will be presented. This includes past, present and future Martian surface sensors and also the techniques and analogues used in reproducing the Martian environment in a laboratory. Laboratory Simulations: At Aarhus University (AU) dust aerosols can be recreated under Mars simulation conditions in an environmental wind tunnel facility. Here the low pressure and temperature conditions can be reproduced in a large chamber (3m*1m) within which a re-circulating wind tunnel is housed. Mars analogue dust can be injected and studies of bot dust deposition and re-entrainment can be performed as well as Aeolian sand transport. [1].