Delta Theta III
Delta Theta III was the inhabited class M third planet of an unnamed star system. It was the homeworld of the Delta Theta III aborigines, a  species who were protected by an entity they regarded as their god, as it viewed the aborigines as its "children", and guided them in their evolution. The planet had rain forests and a northern continent.

A Federation scouting mission had reported the presence of a native population. The , during a series of exploratory and contact missions in 2270, was ordered to investigate the planet. In that year, the planet's lifeforms appeared far younger than was geologically expected, considering the age of its primary.

After an assessment of the planet and its civilization, Captain James Kirk sent a message to Starfleet Command recommending that this planet be quarantined and that no Federation vessel, under any circumstances, should approach the planet. ()

See also 
 Theta III

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Delta Theta 03
Homeworlds