Johnston Atoll

• Discovery and Early Use: Johnston Atoll was discovered accidentally in 1796 by American ship captain Joseph Pierpont, but it was later named after Captain Charles J. Johnston, who sighted it in 1807. • Military Control: The U.S. Navy took formal control of Johnston Atoll in 1934, and it became a key military outpost in the Pacific for most of the 20th century. • World War II Role: During World War II, the atoll was fortified and used as a refueling and supply base for aircraft and ships operating in the Pacific theater. • Atomic Testing: In the 1950s and 1960s, Johnston Atoll was a major site for high-altitude nuclear tests, including the infamous "Starfish Prime" hydrogen bomb test in 1962. • Missile Defense Testing: The atoll was used for testing anti-ballistic missile systems and as a launch site for Thor and later Nike Hercules missiles during the Cold War. • Chemical Weapons Storage and Disposal: Johnston Atoll became the primary storage and disposal site for U.S. chemical weapons in the Pacific, with the Johnston Atoll Chemical Agent Disposal System (JACADS) operating from 1990 to 2000. • Accidental Chemical Leaks: The site experienced several accidental chemical agent leaks, including a 1969 incident where sarin gas leaked from a bomb, requiring major cleanup and safety improvements. • Biological Weapons Testing: The U.S. conducted top-secret biological weapons tests at Johnston Atoll in the 1960s, including "Project SHAD," to study the dispersal of biological agents. • Ecological Impact: Despite heavy militarization and contamination, Johnston Atoll remains an important refuge for seabirds and marine life, and is now part of the Pacific Remote Islands Marine National Monument. • Abandonment and Legacy: The atoll was officially closed as a military base in 2004, and most of the infrastructure was dismantled, leaving behind a complicated legacy of nuclear and chemical contamination.