Planetesimals Are Buffeted by Wind in their Nebula, Throwing Debris into Space

Before planets form around a young star, the protosolar disk is populated with innumerable planetesimals. Over time, these planetesimals combine to form planets, and the core accretion theory explains how that happens. But before there are planets, the disk full of planetesimals is a messy place. The history of rocky objects smashing into each other …