Most of the atomic matter in the Universe courses through the dark, vast spaces between galaxies. This diffuse gas cycles into and out of galaxies multiple times. It will form new stars and become swept up in violent stellar end-of-life processes. Astronomers believe that this gaseous cycle lies at the heart of galaxy evolution. Yet, it has been difficult to observe directly. Owing to the vastly improved capabilities in space-based UV spectroscopy with the installation of the Cosmic Origins Spectrograph on the Hubble Space Telescope, observations and simulations of this diffuse material have emerged at the frontier of galaxy evolution studies. In the last decade, we have learned that Milky Way mass galaxies harbor enough material outside of their visible disks to sustain star-formation for billions of years. Remarkably, our observations indicate that most of the heavy elements on earth cycled back and forth multiple times through the Milky Way’s extended halo before the formation of the solar system. In the spirit of MS-DOS adventure games, I have designed a fully interactive colloquium that operates on a complex network of powerpoint hyperlinks and real-time voting by audience members (no software required!). In this adventure, you will choose any of 36 possible tracks on which to explore observational and simulated signatures of cosmic gas flows.
Speaker: Jessica Werk
Host: Dr. James Wadsley