Nabu is a star system located in the Alpha Quadrant, and contains a large asteroid belt and at least one inhabited planet.

In 2265, the USS Enterprise (NCC-1701) was patrolling at the edge of the system, when they decided to investigate the planet, and discovered an electromagnetic field surrounding it. Captain James T. Kirk leads a landing party to the surface and discovered a large group of prisoners, led by Targu. (TOS comic: "The Devil's Isle of Space")