Hanab is a protostar that as of the 23rd century was newly charted. The Federation had sent unmanned probes to study it but they had mysteriously vanished.
According to a Starfleet Academy simulator scenario, the Hycombia Confederation also had sent a modified research vessel there but it was trapped in its gravity field.
The Federation sent USS Banting to investigate and monitor its unusual radiation bursts. While there, they detected the high energy subspace signal generated by the Hycombian ship and managed to rescue it. (TOS video game: Starfleet Academy Starship Bridge Simulator)