Lagrange Points in a Binary Star System

The Lagrange points are points of gravitational equilibrium. The L1, L2, and L3 points are locations about which an object, such as a satellite, can be placed in a quasi-stable orbit with only small corrections needed. The equipotential surface passing through the L1 point defines the Roche lobes of the stars. If either star grows larger than its Roche lobe, mass transfer from that star to the other will be initiated.

Mathematica generated image showing the Lagrange points in a binary star system created by Jeff Bryant (jeffb@wolfram.com)