The image above is of the Kepler supernova remnant, first discovered in 1604, and one of only a few Type Ia supernovas known to have exploded in the Milky Way galaxy. Its proximity and its identifiable explosion date make it an excellent object to study.
In a new study, researchers from NC State have found that the supernova was triggered by an interaction between a white dwarf and a red giant star, rather than the interaction between two white dwarf stars. These results could imply that many Type Ia supernovas have a similar origin, but the authors warn that they are unsure whether Kepler was a typical explosion.
Their results appear in the Astrophysical Journal.