5) Milky Way Analogs in the Local Universe

Abstract: Our Milky Way Galaxy provides an ideal opportunity for us to study galaxy evolution on small scales, due to our position within the Milky Way’s disk. However, this position makes it difficult to connect the Milky Way to the wider galaxy population. Milky Way analogs allow us to consider how the Milky Way might appear to an external observer, and so in turn allow us to bridge this divide. Here, we begin by presenting a sample of 62 galaxies identified as Milky Way analogs and observed as part of the MaNGA spectroscopic survey. We showcase the properties of these analogs’ stellar populations and ionised gas components, with comparisons made to our knowledge of the Milky Way. We then present a series of large Milky Way analog samples selected from the GALEX-SDSS-WISE Legacy Catalog using various complementary “analog” definitions, in order to better understand the Milky Way’s position within the wider population of nearby galaxies. We also present a series of Andromeda analog samples, in order to likewise understand how Andromeda compares to other galaxies in the local Universe. We discuss the implications of analogs’ properties for understanding the Milky Way’s uniqueness, as well as for understanding both the Milky Way and Andromeda in the wider context of extragalactic astronomy.

Bio: Nicholas Boardman is currently a postdoctoral researcher at the University of Utah. His research concerns the topic of galaxy evolution, with a particular emphasis on late-type galaxies and on Milky Way analogs in recent years.