Underwater atomic bomb test

This video is pretty impressive:



The website offers the following description:

The Hardtack Umbrella event was a Los Alamos and Dept of Defense nuclear explosion shallow depth underwater shot (150 ft.), June 8, 1958, at Enewetak. The test was weapons effects related and the yield was 8 kilotons.

Hard to believe anyone would leave a ship there like that, though.