Experimental investigation of the formation of accretionary rims around chondrules and the formation of chondrite parent bodies

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Chondrites are the most common class of meteorites, which mainly consist of two components, the chondrules, which are millimeter-sized solid beads, and the matrix, which consists of micrometer-sized dust grains. These chondrites have been mineralogically, chemically and isotopically very well analyzed so that detailed information of their properties is available. However, the physical conditions under which the chondrite parent bodies were formed in the young Solar System are mostly unknown. Age determination of the chondrites showed that their formation dates back to the very first few million years of our Solar System. Since then, the chondrite parent bodies have remained mostly unchanged and have, thus, preserved their pristine structures. Therefore, knowledge about the physical processes that lead to the observed internal structures can provide valuable insights into the dominant processes during the formation time of planetesimals, e.g. their typical collision velocities. Here we propose to investigate the collision physics of pre-chondritic materials in laboratory experiments and to compare the experimental outcomes with real chondritic meteorites. In addition to that, we will investigate the formation of fine-grained chondrule rims, which are frequently found in many chondrites and whose origin is still a matter of debate. The results of our investigations will help to identify the processes by which larger bodies form in the young Solar System.