The researchers believe that this faint supernova may have left behind a surviving portion of the dwarf star, a sort of zombie star.
While examining Hubble images taken years before the stellar explosion, astronomers identified a blue companion star feeding energy to a white dwarf, a process that ignited a nuclear reaction and released a weak supernova blast, Type Iax, which is less common than its brighter cousin, Type Ia.
Saurabh Jha of Rutgers University in Piscataway, New Jersey, said that astronomers have been searching for decades for the star systems that produce Type Ia supernova explosions and Type Ia's are important because they're used to measure vast cosmic distances and the expansion of the universe.
Jha added that they have very few constraints on how any white dwarf explodes and the similarities between Type Iax's and normal Type Ia's make understanding Type Iax progenitors important, especially because no Type Ia progenitor has been conclusively identified. This discovery shows us one way that you can get a white dwarf explosion.
The astronomers hope their new findings will spur the development of improved models for these white dwarf explosions and a more complete understanding of the relationship between Type Iax and normal Type Ia supernovae and their corresponding star systems.
The weak supernova, dubbed SN 2012Z, resides in the host galaxy NGC 1309 which is 110 million light-years away and was discovered in the Lick Observatory Supernova Search in January 2012.
The study was published in the journal Nature.