... Credit Copyright: NASA , HST Artist's Visualization Explanation: Our Sun is unusual in that it is alone - most stars occur in multiple or binary systems . In a binary system, the higher mass star will evolve faster and will eventually become a compact object - either a white dwarf star, a neutron star , or black hole . ... Here gas from a blue giant star is shown being stripped away into an accretion disk around its compact binary companion. ... Publications with keywords: accretion disk . ...