Dust Aggregates in the ISM

Interstellar dust is a crucial component of the ISM, and as an extension of that, plays a significant role throughout the different stages that lead to planet formation. Dust is not only relevant for planet formation but almost every kind of astrophysical observation. In fact, it is so pervasive and prevalent that even the modern zeitgeist carries a decent idea of its effects. Most infamous example is that of Tabby's Star, whose fluctuations of up to 22% reduction in brightness, first observed by none other than citizen scientists sparked numerous debates around the origin of such drop. Although still a matter of debate, several hypotheses explaining the cause involve dust in some way or the other.

This chapter introduces what kind of geometries have been studied in which these dust particles are thought to occur in.