Astronomy Colloquium

In the last several years, groundbreaking instruments have detected significant Lyman-alpha emission from the circumgalactic media (CGM) of z>2 galaxies, providing an initial corroboration to results from years of absorption line studies. Taken together, these indicate the presence of vast reservoirs of gas that we are only just beginning to observe and understand. To probe when star formation declines throughout the universe, we need to conduct similar observations at lower redshifts, moving into the UV. The Faint Intergalactic medium Redshifted Emission Balloon (FIREBall-2) is a balloon-born UV multi-object spectrograph designed to detect Lyman-alpha emission from the circumgalactic medium (CGM) around z~0.7 galaxies. In this talk, I will discuss the science drivers for this mission and its current status as we prepare for a Fall 2017 flight. In addition to groundbreaking science, FIREBall-2 will flight test several new technologies in a balloon setting, including photon counting, high efficiency UV detectors. I will discuss these technologies in the context of their impact on future space missions.