Abstract
Plotting the mass–density of a wide range of astronomical objects as a function of their mass reveals that the vast majority of these objects fall along a “cohesive object sequence” that extends all the way from asteroids to the largest stars. Trends and features within this sequence reflect fundamental astronomical processes and phenomena, including the gravitational contraction of progressively higher-mass planets and the onset of nuclear reactions within stars. Meanwhile, compact stellar remnants fall well off this sequence, reflecting their extreme natures. This type of plot is therefore useful both for showcasing the relationships and connections between a wide range of astronomical objects and for clarifying the distinctions used to identify particular types of objects.