They won't see each other moving at the speed of light though. This example is covered in any class on relativity. Having an approach velocity between two objec

They won't see each other moving at the speed of light though. This example is covered in any class on relativity. Having an approach velocity between two objects at the speed of light or greater is different than accelerating a frame of reference to c. When an approach velocity is c, nothing is actually _moving_ at c.