Star Trek: The Lionhearted Wiki

The Relva IV Research Station was a small space station orbiting the fourth planet in the Relva System.

By the late 2360s, Doctor Gustav Kragen and his assistant Gretel Vandermark were among its inhabitants.

In 2371 the USS Bradbury arrived to take the pair and a  sensor system to Starbase 39-Sierra.  ("Blinded by Science")