Discovery of a Peculiar Supernova
Discovered in 2005, a Type Ib Supernova SN 2005cz had puzzled astronomers for their peculiar nature. It is unusually faint, quick to fade, and located in an elliptical galaxy ‑ an unexpected site for such supernova to happen. Subaru’s data have shown that these peculiarities are well explained by rather ‘normal’ core-collapse supernova from a less-massive progenitor star (with 10 solar masses) than other Type Ib supernovae. This is the first evidence of the theoretical prediction that stars in the 8-12 solar mass range can explode as supernova. Subaru’s finding proves the stellar evolution theory of supernovae and provides an important clue to the chemical evolution of galaxies.