Here's a breakdown:
* Gravity: Every object with mass exerts a gravitational pull on every other object with mass. The more massive the object, the stronger its gravitational pull. The closer two objects are, the stronger the gravitational pull between them.
* Binary Stars: In a binary star system, two stars are close enough to each other that their mutual gravitational attraction dominates their motion. They orbit around a common center of mass, known as the barycenter.
* Balance of Forces: The stars in a binary system are constantly trying to pull each other closer due to gravity. However, their orbital motion provides a centrifugal force that counteracts this gravitational pull. This balance between gravity and centrifugal force keeps the stars in their orbits and prevents them from colliding.
Therefore, it's the mutual gravitational attraction between the two stars that holds them together in a binary system.
