SupernovaeSupernovae occur in massive stars that have exhausted their nuclear fuel and can no longer prevent gravitational collapse of the core. After a compression to supernuclear densities, the core rebounds - giving rise to a shock wave that propagates out of the star, blowing off the outer layers and leaving behind a neutron star or black hole. The conditions right above the newly-born neutron star are thought to be sufficient to enable the formation of heavier elements via rapid neutron captures on neutron-rich unstable nuclei interspersed with beta decays - the r-process. Because most of the structure properties and neutron capture reactions on nuclei in or near the r-process path are unknown, it is still uncertain whether supernovae are a viable site for this mechanism to form the heavy elements. FRIB will be the only facility to access the vast majority of r-process nuclei. Measurements at FRIB will finally enable r-process models to have a firm empirical basis.