USNS Observation Island (T-AGM-23)

USNS Observation Island (T-AGM-23)

USNS Observation Island (T-AGM-23), also known as ex-MA-28, ex-YAG-57, ex-E-AG-154, Empire State Mariner, is the historic naval vessel that in 1969 launched the first Poseidon Fleet Ballstic Missile ever successfully deployed from a vessel at sea, earning the ship and crew the Meritorious Unit Commendation. The ship is currently one of two Missile Range Instrumentation Ships operated by the Military Sealift Command. One of the radars it carries is the AN/SPQ-11 Cobra Judy Passive Electronically Scanned Array radar.

USNS Observation Island operates worldwide, monitoring compliance with strategic arms treaties and supporting U.S. military weapons test programs. Observation Island carries an Air Force shipborne phased-array radar system for collecting data on missile tests. The ship is operated by Military Sealift Command for the Air Force Technical Applications Center at Patrick Air Force Base.

USNS Observation Island was built as a "Mariner" class merchant ship, launched in August, 1953, and was acquired by the Navy in September 1956 for use as a fleet ballistic missile test ship. The vessel was converted at Norfolk Naval Shipyard, and kept in reserve as a Maritime Administration asset from 1972 until 1977. In August 1977, Observation Island was reacquired by the U.S. Navy and transferred to Military Sealift Command, where it was reclassified as T-AGM 23, a missile range instrumentation ship.