Aquanaut
The first person to stay at the bottom of the ocean for 24 hours was a man from France. His name was Robert Sténuit. This happened in September 1962. The United States Navy had a program in the 1960s called SEALAB in which military aquanauts and scientists spent time on the ocean bottom. This program ended in February 1969 after aquanaut Berry L. Cannon died from breathing too much carbon dioxide.