The discussion centers on the potential water pressure beneath Europa's ice, which is estimated to be 10 to 15 miles thick, with a surface gravity of 0.134g. It explores the feasibility of using submarines, like the Los Angeles class, which could theoretically dive to depths of 2,160 meters on Europa, although challenges exist with breaking through the ice. The conversation also touches on the need for advanced technology, such as rockets capable of launching 6,000-ton payloads to Jupiter, and the complexities of maintaining operational integrity at extreme temperatures. Thermal methods for ice penetration are suggested as a viable approach, alongside the idea of constructing submersibles without gas pockets to withstand high pressures. Overall, the exploration of Europa remains a challenging yet intriguing prospect for future missions.