Rel was small, barren planetoid in the Tynna sector. A nearly-spherical chunk of rock, it was the only planet of the Rel system.
It was theorized to be either an escaped moon or a fragment of an unknown larger planet that was fractured long ago. During the later months of the Clone Wars, it was the site of a small space battle between General Grievous and Jedi Knight Shahmzar Aonda-Alci. However, the battle was but a feint to draw attention away from Duro, Grievous's next target.