Invited_talk abstract details

Since their recognition as a distinct astrophysical phenomenon more than two centuries ago, the role of morphology in planetary nebula (PN) research has evolved from mere description to a key tool in understanding their origins, structure, and evolution. Over the last century the study of morphology has revealed many profound insights into the PN phenomenon. For instance, we learned that PNe are associated with the late stages of stellar evolution; that they have complex, three-dimensional structures; that their shapes evolve continuously from the moment of formation to their dispersal into the ISM; that their macroscopic symmetries are well correlated with their chemical properties and the masses of their central stars; that the structures on all spatial scales result from a variety of causes, and so on. A revival over the past two decades in PNe morphological studies springs from a combination of factors, including the advent of wide-area, high dynamic range detectors; the growing archive of high resolution images from the X-ray to the mid-IR; and the advent of numerical simulations of the co-evolution of PNe and their central stars. Yet the story of PN formation from their immediate precursors, the AGB stars, is not yet fully written. In this area PN morphology continues to inspire, provide context, or serve as an ultimate standard of comparison for many investigations in this area of astrophysics. After a brief review of the remarkable successes of PN morphology, I will summarize how this tool has been employed in more than 150 papers over the last half-decade to advance our understanding of PNe.