Copernicus. Galileo. Hubble. For ages, humans have looked up at the night sky to ponder the secrets of the universe. The flickering stars have been the stuff of fascination and research for millennia, from men and women who mostly turned their gaze ever upward to study the vastness of space. Yet today, a group of University of Notre Dame astrophysicists is going down — way down — in a new attempt to gain an understanding of the evolution of stars.