Unanswered questions linger a year after the implosion of the Titan submersible during its deep-sea voyage to the wreckage of the Titanic. Tuesday marks one year since the North Atlantic disaster, but it will be at least two more months before the U.S. Coast Guard releases the findings of a high-level investigation. In the meantime, undersea exploration continues, albeit with changes based on some of the lessons learned from the Titan. The implosion killed the submersible’s operator, Stockton Rush, and four others. Family, friends and fellow sea explorers plan to hold both public and private ceremonies this week to honor the victims. Unanswered questions linger a year after the implosion of the Titan submersible during its deep-sea voyage to the wreckage of the Titanic. Tuesday marks one year since the North Atlantic disaster, but it will be at least two more months before the U.S. Coast Guard releases the findings of a high-level investigation. In the meantime, undersea exploration continues, albeit with changes based on some of the lessons learned from the Titan. The implosion killed the submersible’s operator, Stockton Rush, and four others. Family, friends and fellow sea explorers plan to hold both public and private ceremonies this week to honor the victims. AP Technology and Science