Lithium hydride
Before the Castle Bravo nuclear weapons test in 1954, it was thought that only the less common isotope lithium-6 would breed tritium when struck with fast neutrons. The Castle Bravo test showed (accidentally) that the more plentiful lithium-7 also does so under extreme conditions, albeit by an endothermic reaction.
Daigo Fukuryū Maru
The "Daigo Fukuryū Maru" encountered the fallout from the U.S. Castle Bravo nuclear test at Bikini Atoll, near the Marshall Islands, on March 1, 1954. When the test was held, the "Daigo Fukuryū Maru" was catching fish outside the danger zone that the U.S. government had declared in advance. However, the test was more than twice as powerful as predicted, and changes in weather patterns blew nuclear fallout, in the form of a fine ash, outside the danger zone. On that day, the sky in the west lit up like a sunset. Seven minutes later, the sound of the explosion arrived, with fallout reaching the ship two hours later. The fishermen attempted to escape from the area, but they took time to retrieve fishing gear from the sea, exposing themselves to radioactive fallout for several hours.