The Shinkai 6500 is a famous crewed deep-sea research submersible built in 1989 and operated by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). It is one of the very few human-occupied vehicles capable of diving to depths of 6,500 meters (21,300 feet), allowing researchers to explore deep-sea ecosystems, hydrothermal vents, and earthquake zones. [1, 2]