New three-dimensional measurements of the positions and velocities of stars, in particular from the Gaia observatory, have provided unprecedented information on the dynamics of the Milky Way and nearby galaxies. Stellar streams and phase-space structures have been characterized, pointing towards an active recent accretion history by the Milky Way. In this talk, I will discuss how these observations inform hierarchical structure formation, the Milky Way, the Local Group of galaxies, and the nature of dark matter. I will discuss what we can expect from future Gaia data and future astrometric observations.
Aut. Qtr. Colloq. committee: R. Blandford (Chair), A. Kapitulnik, R. Laughlin, L. Senatore
Location: Hewlett Teaching Center, Rm. 200