Making the Milky Way Galaxy: A Work in Progress

The Milky Way was formed by collapse of gas in an extensive halo of dark matter.  While most stars in the Milky Way were created in the distant past the process continues to this day, fueled by the accretion of fresh gas.  I will discuss recent observations relevant to the continued evolution of our Galaxy, with emphasis on Green Bank Telescope measurements of a very large cloud of gas that is on a collision course with the Milky Way disk.  It is bringing in enough new material to make more than a million solar systems like our own, but its origin and ultimate fate are uncertain.