Here we explore peer effects in science, outlining the ways in which scientists affect each other’s outcomes and behavior. In particular, we look at the influence of star scientists on their colleagues, showing that both the productivity of a department and the quality of future faculty increases after a luminary is hired. We detail the negative affect that a star scientist’s death can have on her colleagues, effects which speak to the power of the “invisible college” that binds scientists together in shared interests and ideas. Lastly we outline examples of how changes to the invisible college can have far-reaching impact, demonstrating the highly connected nature of science.