State, U.S., comprising a group of islands in the central Pacific Ocean. Area: 6,461 sq mi (16,734 sq km). Pop. (2009 est.): 1,295,178. Capital: Honolulu. Hawaii lies 2,397 mi (3,857 km) west of San Francisco. The state's major islands are, from west to east, Niihau, Kauai, Oahu, Molokai, Lanai, Kahoolawe, Maui, and Hawaii; there are 124 islets. The state's active volcanoes include Mauna Loa and Kilauea. The majority of the state's residents live on Oahu. The original Hawaiians were of Polynesian origin and came from the Marquesas Islands c. 300 CE. Capt. James Cook visited the islands in 1778 and called them the Sandwich Islands. At the beginning of the 19th century, Kamehameha I united the group under his rule. American whalers began to stop there; they were followed in 1820 by New England missionaries, and Western influences changed the islands. While Kamehameha III in 1851 placed Hawaii under U.S. protection, a coup fomented by U.S. sugar interests resulted in the monarchy's overthrow and the establishment of a Republic of Hawaii (1893). In 1898 the new republic and the U.S. agreed on annexation, and in 1900 Hawaii became a U.S. territory. The bombing of Pearl Harbor by the Japanese in 1941 led to U.S. involvement in World War II, and Hawaii became a major naval station. Hawaii became the 50th U.S. state on Aug. 21, 1959. Its largest industry is tourism. It is also a world astronomy centre, with telescopes atop Mauna Kea.