SEA OF JAPAN (July 26, 2010) The Los Angeles-class attack submarine USS Tucson (SSN 770) transits the Sea of Japan while leading a 13-ship formation. The Republic of Korea and the United States are conducting the combined alliance maritime and air readiness exercise "Invincible Spirit" in the seas east of the Korean peninsula from July 25-28, 2010. (U.S. Navy photo by Mass Communication Specialist 3rd Class Adam K. Thomas/Released)