Nova Atar III was a planet, a class M planet located somewhere in the space of the galaxy's Alpha or Beta Quadrants, the third planet in orbit of the Nova Atar star system.
History and specifics[]
By the 2260s decade, Nova Atar III was a holding of the Federation, and was home to the Smithsonian Annex, a museum complex which presented artifacts from all over the Alpha and Beta Quadrants. (TOS video game: Judgment Rites)