Astromaterial sciences is the study of materials under the extreme conditions of space. This talk will focus on the origin and evolution of large molecules and nano-sized dust grains in space and their influence on the processes that shape the universe around us.
At the end of their life, stars return most of their material back to the interstellar medium. This material undergoes a complex evolution in the interstellar medium before it becomes part of the next generation of stars and planets. Specifically, large molecules and nano-sized dust grains condense in the ejecta of stars as it cools because of expansion. The composition of this material can be analyzed through remote infrared spectroscopic observations revealing the tell-tale signatures of the compounds present. In addition, stardust is isolated from meteorites whose isotopic composition betrays their origin in stellar ejecta. These data have revealed a highly diverse dust inventory, reflecting the varied physical and chemical conditions in their birthsites.
Interstellar dust is highly processed during its sojourn from its birthsite (stellar outflows and explosions) to its incorporation into planet forming systems. Of particular importance is processing by cosmic rays in the interstellar medium and by strong shocks due to supernova explosions. The latter leads to rapid destruction due to sputtering by impacting gas ions due to grain-grain collisions. The planet formation process is initiated by the agglomeration of submicron-sized dust grains driven by weak van der Waals forces. Over the last decade, a variety of laboratory and theoretical studies have elucidated the various factors involved in this growth process.
This talk will highlight various aspects of this lifecycle of interstellar dust and the processes that play a role in its evolution.
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