Caladan Oceanic’s 2021 Ring of Fire Expedition, Part II, continued with multiple dives to Challenger and Sirena Deeps. During the dives sponsored by American Larry Connor, the team was able to retrieve the first mantle rocks from the bottom of the ocean containing microbacterial mats. It also saw the first Spaniard, Hector Salvador of Barcelona, descend to the bottom of the Mariana Trench — thus making him the deepest diving Spanish citizen in history.