Initial Aggregation of Fine-Grained Rim Dust Layers*

            Hints of what occurred in the early protoplanetary disk can be obtained by examining meteorites and specifically the mm-sized pebbles found inside called chondrules. The majority of chondrules contain a fine-grained dust rim that is believed to dampen the impact energy between chondrules during collisions allowing them to more easily stick together. A proper understanding of a fine-grained rim’s structure is essential to providing insight into the early environment of a protoplanetary disk [1][2]. It is currently assumed that in such an environment, dust layer growth occurs naturally starting with the initial deposition of material. The mechanism driving these dust deposits is informed by several factors including, surface chemistry, particle size, particle shape and particle charge. However, little research data exists for the initial deposition phase at protoplanetary impact velocities. In this presentation, experimentally driven data will be employed to explain dust behavior during the initial dust deposition and restructuring phase. A technique for studying dust aggregation behavior will also be presented. As a result, this research has application elsewhere including dust mitigation on the lunar and Martian surfaces as well as the soiling of solar panels in both Martian and Earth environments.

 

¹ C. Xiang, A. Carballido, R.D. Hanna, L.S. Matthews, and T.W. Hyde, Icarus 321, 99 (2019).

² Hanna, R.D., Ketcham, R.A., 2018. Earth Planet Sc Lett 481, 201–211.