Scientists return to survey Bikini A-bomb test site

Scientists have surveyed the site of the first underwater nuclear explosion, which took place at Bikini Atoll on 25 July, 1946.

They found a crater on the seafloor is still present, along with the wrecks of the many battleships that were experimentally exposed to the blast. Survey team leader Dr Art Trembanis, from the University of Delaware, spoke to our science correspondent Jonathan Amos.