SAN FRANCISCO -- An underwater expedition along the California coast has revealed for the first time a sunken World War II-era aircraft carrier once used in atomic tests in the Pacific.

The expedition led by famed oceanographer Robert Ballard captured on Tuesday the wreckage of the USS Independence, located half a mile under the sea in the Greater Farallones National Marine Sanctuary.

Scientists aboard the ocean research ship E/V Nautilus lowered two submersibles to the ocean floor to find a Hellcat fighter plane, anti-aircraft guns, hatches and the ship's name on the hull.

The Independence was deliberately scuttled in 1951.

Samples of marine life growing on the ship will be brought onboard to be tested for possible radioactivity remaining from the bomb tests, as well as to be analyzed for the effects of climate change.