Events - Event View

Our speaker this month is Dr. Ana Bonaca. Dr. Bonaca’s presentation will outline her work on Star Streams in the Milky Way Galaxy. She writes, “Globular clusters are large congregations of stars, which gradually lose their members to form thin and long stellar streams. In pristine conditions, these streams have a nearly uniform density, however, new observations of one such structure in the Milky Way halo have revealed a likely site of perturbation. The on-sky morphology suggests a recent, close encounter with a massive and dense perturber. Known baryonic objects are unlikely perturbers based on their orbital properties, but observations permit a low-mass clump of dark matter as a plausible candidate. This discovery opens up the exciting possibility that detailed observations of streams could measure the abundance of dark-matter substructure and thus shed light on the nature of dark matter.”

Dr. Bonaca is a Fellow at the Institute for Theory and Computation, hosted by the Harvard - Smithsonian Center for Astrophysics. Her specialty is stellar dynamics and her research aims to uncover the structure and evolution of our galaxy, the Milky Way, especially the dark matter halo that surrounds it. In her research, she uses space and ground based telescopes to measure the motions of stars and constructs numerical experiments to discover how dark matter affected them. Dr. Bonaca obtained an Astronomy PhD from Yale University and was awarded the Brouwer prize for a distinguished thesis.