Nervala IV was the uninhabited fourth planet in its star system. The planet generated a distortion field, which prevented the use of transporters and shuttles. The distortion field could only be penetrated when Nervala moved closer to its primary, which happened every eight years. The planet also experienced earthquakes from time to time.
In the 2360s, a Starfleet research station, Nervala station, was located on this planet. The crew was forced to evacuate in 2361 due to the changing conditions. The USS Potemkin arrived and sent an away team, including Lieutenant William T. Riker. They were all successfully evacuated, however, unknown to them, a duplicate of Riker, Thomas Riker, was created by a transporter accident; Thomas remained on the planet while Will Riker made it back to the Potemkin. Thomas was rescued in 2369 by the USS Enterprise-D when it visited the planet to retrieve the data left by the research team. (TNG: "Second Chances")