Zeta Reticuli was a star system. When he was trapped on Earth in 1957, the Tremas Master sent a distress signal to the Tzun canton on Zeta Reticuli and offered to help them conquer Earth in return for his TARDIS and a new regeneration cycle. (PROSE: First Frontier)
The planet Nocturne was "smack in the middle" between the systems Tau Ceti and Zeta Reticuli. (AUDIO: Nocturne)