Professor of Astronomy Allen Shafter is a world’s expert on a class of eruptive variable stars called “novae”, or “new stars”. The nature of these strange objects remained mysterious for centuries, but they are now understood to arise from explosions on the surfaces of extremely dense white dwarf stars, and are likely a key source of the variety of chemical elements that enrich the universe. Prof. Shafter’s new book, “Extragalactic Novae: A historical perspective” elucidates how astronomers came to understand these fascinating objects, how their study helped launch the field of extragalactic astrophysics, their current role in observational cosmology, and more.