Jedi Master Anakin Skywalker and his family along with Jedi Master Obi-Wan Kenobi had been traveling through hyperspace for awhile. When Luke Skywalker found a pirated broadcast on an imperial channel that he'd been monitoring. The entire family listened in to the uplifting message, and after hearing it, they made a decision that after fifteen years the Skywalker and Kenobi families would come out of hiding. So with one call to an old friend of theirs the two families changed their course and headed to join the Alliance.