Step forward the Titan Submarine, a proposal that NASA has just awarded a second round of funding through their Innovative Advanced Concepts (NIAC) program. It is very much just a concept at the moment, but it is promising nonetheless. Aside from Earth, Titan is the only place in the solar system that has bodies of liquid on its surface, making it a rather attractive place to explore. But while a number of proposals have been put forward to take a closer look, none have come to fruition. Phase II of the Titan Submarine: Exploring the Kraken Mare effort will focus on advancing the Technology Readiness Level (TRL) of the concept by (1) retiring risks found in the Phase I design…