![](http://upload.wikimedia.org/wikipedia/commons/thumb/1/12/Supernova_remnant_N103B.jpg/360px-Supernova_remnant_N103B.jpg)
A type Ia supernova (read: "type one-A") is a type of supernova that occurs in binary systems (two stars orbiting one another) in which one of the stars is a white dwarf. The other star can be anything from a giant star to an even smaller white dwarf. Image is Supernova remnant N103B taken by the Hubble Space Telescope.