article_snippet: : A white dwarf accumulates material from a stellar companion until it undergoes runaway nuclear fusion and explodes.
article_snippet: Two white dwarfs merge until Two white dwarfs merge until their combined mass causes an explosion combined mass causes an explosion.
article_snippet: A star at least nine times the mass of the sun eventually experiences a core collapse as the sun fuel runs out, causing the sun to explode.
article_snippet: A star undergoes core collapse but most of star outer hydrogen has already been lost to stellar winds.
article_snippet: Often, the secondary star is obliterated in a thermonuclear supernova explosion, or pushed away at a more sedate speed.
article_snippet: the secondary star is 'pushed' away because the loss of the secondary star companion means the secondary star no longer has a star to orbit, but retains the secondary star forwards momentum, so the secondary star is flung into space.