Dr. Devon Burr

Aeolian Sediment Movement Under Titan Conditions: Wind Tunnel Experiments and Modeling

Submitted to the Planetary Geology and Geophysics Program
May 5, 2006 

PROPOSAL SUMMARY

The objectives of this work are to conduct wind tunnel experiments and complementary modeling of aeolian sediment transport under Titan conditions, in support of interpretation of Cassini-Huygens data.  We propose to conduct experiments in the Venus Wind Tunnel (VWT) at NASA Ames Research Center to assess sediment movement criteria on Titan.  During year 1 of this 3-year proposal, the VWT will be refurbished for equivalent Titan pressures at terrestrial temperatures (~12 bar) according to the included Planetary Major Equipment proposal.  We will also make theoretical calculations of saltation trajectories using previously developed models.  In year 2, we will assess the threshold for sediment movement under simulated Titan conditions.  Besides determining the threshold friction wind velocity at particle lift-off, we will measure lift-off angles and velocities as input into our models to estimate saltation trajectory for comparison with experimental results.  During year 3, we will measure individual particle velocity and overall particle flux by grain size, and we will compare the experimental results with theoretical calculations.  The physical results of all experiments will also be used to investigate small-scale bedforms.  This fundamental research is essential to understanding aeolian sedimentary processes on Titan.  It will also provide information necessary to meaningfully interpret Titan features hypothesized to be the result of aeolian sediment movement.  By furthering understanding of the formation and conditions for features on Titan's surface, this proposal accords with the program goals of “gathering, synthesis, analysis, and comparative study of data that will improve the understanding of the extent and influence of planetary geological and geophysics processes on the bodies of the Solar System…”  In response to NASA Strategic sub-goal 3C, this proposal will "advance scientific knowledge of the origin and history of the solar system, ..."