binary system

Black holes in binary systems pull in matter from companion stars, creating relativistic jets that transform these systems into "micro-quasars."

The discovery opens up new questions about how planets form and persist in binary systems.

This strange new world orbits around two stars at once, which dance around each other in what astronomers call a binary system.

It’s a binary system; a choice of extremes.

In close binary systems, this expansion is so dramatic that the dying star's outer layers can sometimes completely engulf its companion.