Aeolian processes on the terrestrial planets: Recent observations and future focus

Aeolian dune fields have been described on Earth, Mars, Venus, and Titan. The amount and fidelity of data being returned from orbiting spacecraft and landers have enabled a new era in aeolian studies. This progress report presents an overview of the latest planetary geomorphic studies characterizing aeolian processes on extraterrestrial surfaces. Our understanding of aeolian processes on other planetary surfaces comes largely from Earth analog studies, along with wind tunnel experiments and theoretical modeling. However, an important difference is that unlike terrestrial dunes most dunes on Venus and Mars are composed primarily of basaltic particles. Additional research is needed to understand how basaltic particles weather both physically and chemically so that it will be possible to apply traditional sedimentological concepts, such as sediment maturity, to understanding aeolian processes on Venus and Mars. It may also be possible to characterize sediment maturity and provenance through remote sensing data once we have a better understanding of basaltic sediments. Although there have been a variety of dune forms identified on the surfaces of the other terrestrial planets, the only dune form found on all of them is linear dunes. Even though linear dunes are the most common dune forms on Earth, we currently have a poor understanding as to how they are formed, and additional work is needed to understand these features.