Merak II was the inhabited second planet of its star system. The planet was a Federation member. Plant life on this planet was the source of the oxygen in the atmosphere. Prior to stardate 5818, Merak II was admitted to the Federation. In that year, the planet experienced a bacterial botanical plague. The plague was treated with a toxic ore, known as zenite, which was acquired by the USS Enterprise. (TOS: "The Cloud Minders" ) In 2370, Quark claimed that Elim Garak had ordered a sizing scanner from Merak II from the Ferengi. (DS9: "The Wire")