Capella Island is a 230-acre uninhabited island and diving spot that is owned by the United States Virgin Islands. It is located about 2 miles south of the island of St. Thomas. It is adjacent to Buck Island, home of Buck Island National Wildlife Refuge, about twice the size of Capella. The two islands are separated by a minor channel. Together Capella, Buck, a…Capella Island is a 230-acre uninhabited island and diving spot that is owned by the United States Virgin Islands. It is located about 2 miles south of the island of St. Thomas. It is adjacent to Buck Island, home of Buck Island National Wildlife Refuge, about twice the size of Capella. The two islands are separated by a minor channel. Together Capella, Buck, and associated islets are sometimes referred to as the Capella Islands.