<p><strong>A supercomputer simulation shows the collision of two neutron stars with different masses in one of the most violent events in the universe. The end result is a black hole and a lot of debris from the less massive star, which is broken up by the tidal forces of the more massive one.</strong></p><p dir="ltr">A neutron star is the compressed core left behind when a star, born with between 8 and 30 times the sun's mass, explodes as a supernova. Neutron stars pack about 1.5 times the mass of the sun—equivalent to about half a million Earths—into a ball just 12 miles (20 kilometers) across. These huge explosions are visible from Earth about once a day.</p><p><em>—Text by Dan Vergano and Kurt Mutchler, Photo Editing by Kurt Mutchler</em></p>