SNe Ia Progenitors

Type Ia supernovae progenitors are typically white dwarf stars in binary systems, meaning they have a companion star. Over time, the white dwarf gains material from its partner through stellar winds or by pulling matter off the companion. When the white dwarf reaches a critical mass—close to 1.4 times the Sun’s mass—it becomes unstable and undergoes a thermonuclear explosion. This explosion destroys the star, creating a supernova. These events are important for understanding cosmic distances because their brightness is consistent, acting as “standard candles” for measuring the universe’s expansion.