This project will explore the effects of star formation in early galaxies. This study will aid our understanding of the formation of the heavy elements and their return to the intergalactic medium by supernovae in the first stars and the first galaxies. When such massive stars form, they produce large amounts of ionizing radiation, before ending their lives in prodigious explosions (supernovae). Dr. Shull and his collaborators will use supercomputer simulations together with studies of individual stars to explore the so-called "feedback of star formation" on remaining gas in the intergalactic medium. They will also explore the production of ionizing radiation and the first heavy elements (needed for the formation of planets, comets, and even life) from the earliest stars. ****