Sea Dragon is a two-staged sea-launched super-heavy rocket built by NASA and launched from the South Pacific Ocean in 1983. The rocket was used on a mission to resupply and expand Jamestown with components for a plutonium fueled nuclear power-source.
At 150 m (490 ft) long and 23 m (75 ft) in diameter, Sea Dragon is the largest rocket ever built, and could carry 550 tonnes of payload into Low Earth Orbit.