Using Distant Galaxies as Cosmic Time Machines

The night sky is filled with stars and galaxies whose light was emitted at different times throughout the entire 13.6 billion-year history of the universe. Each one provides us with a snapshot in time, which we can use collectively to gain insight into some of the most fundamental questions about the nature of the universe. When did the first stars and galaxies form? How do galaxies and their stars evolve with time? What causes galaxies to stop forming stars and die? Elizabeth McGrath, associate professor of physics and astronomy will discuss what images from the Hubble Space Telescope are revealing about the early history of galaxies, and how our current theories of galaxy formation and evolution may need to be modified to properly account for recent observational results.