What happens when a star gets hit by a supernova?
There are certain cases where the remaining star survives; this happened to high-mass X-ray binary star systems, pairs which consist of a neutron star or black hole (the remnant of a supernova) and a massive star. The X-rays are produced when some of the material ejected by the star is captured by the supernova remnant.

The most famous of these is Cygnus X-1, the first object widely accepted to be a black hole. The massive star in this pair has the same name as one of our moderators.