The B FH paper described key aspects of the nuclear physics and astrophysics involved in how stars produce these heavy elements. By scrutinizing the table of nuclides, the authors identified different stellar environments that could produce the observed isotopic abundance patterns and the nuclear processes that must be responsible for them. The authors invoke nuclear physics processes, now known as the p-process, r-process, and s-process, to account for the elements heavier than iron. The abundances of these heavy elements and their isotopes are roughly 100,000 times less than those of the major elements, which supported Hoyle's 1954 hypothesis of nuclear fusion within the burning shells of massive stars.