Type Ia supernova lifecycle

Type Ia supernovae occur in a binary star system. Eventually, one of the main sequence stars burns through all of the hydrogen in its core, expanding into a red giant. This may bring part of the surface of the giant star closer to its companion, and mass can overflow from the red giant and be accreted onto the secondary star. When the outside of the red giant is stripped away, all that remains is a white dwarf star. The second main sequence star will also eventually reach the end of its life and expand int