Astronomers led by Dr Stella Kafka of the Carnegie Institution for Science have reported the discovery of a star system, prior to explosion, which will possibly become a type Ia supernova. A composite image of the remnant of Tycho’s star, a type Ia supernova seen in 1572 (NASA / CXC / SAO / JPL-Caltech / MPIA / Calar Alto / O. Krause et al) Type Ia supernovae are violent stellar explosions. Scientists observe their brightness to determine distances...