The search for the missing Titan submersible, a five-person submersible used by OceanGate to view the wreckage of the Titanic, ended on Thursday with the Coast Guard announcing that debris from the vessel had been found, leading to the belief that the pilot and passengers are now dead. The investigation into the cause of the tragedy is ongoing, with a focus on safety protocols and procedures, and is a reminder of the dangers of deep-sea exploration.