Galactic Neighborhood Watch

Gurtina Besla

Post-doc, Columbia University

The Milky Way and its galactic neighbor, the Andromeda Galaxy, are surrounded by a number of smaller satellite galaxies. You may think because these systems are in our galactic backyard that we have learned all there is to know about them, but a number of surprises have been revealed over the past few years. In particular, it appears that the Milky Way's largest satellites, the Large and Small Magellanic Clouds, are recent interlopers in our galactic neighborhood. I'll discuss how we know this and how new measurements are shedding light on the cataclysmic event in our distant future when the Milky Way collides with the Andromeda Galaxy.