The Omicron Theta system was an uninhabited star system in Federation space. In the early 24th century, colonists from Earth built a colony on a planet of the system. The colony's primary mission was scientific in nature. A being known as the "Crystalline Entity" destroyed the colony, as well as all life on the planet, in the mid-2330s.

A Federation starship, the USS Tripoli, responding to a repeating signal located the inactive body of Data on the planet in 2338.

Twenty-six years later, the USS Enterprise-D diverted its course briefly to this system in the search of answers as to Data's origins and the events leading up to the death of the colony. In the course of their investigations, they recovered the body of Lore. (TNG: "Datalore")

• Omicron Theta (primary)
  • Omicron Theta colony (planet)
    • Moon 1
    • Moon 2