R/S RocketShip, formerly M/V Delta Mariner, is a cargo ship operated by Foss Maritime for United Launch Alliance (ULA). Her primary role is transporting components for the ULA Atlas V, Delta IV and Vulcan rockets from the manufacturer, located in Decatur, Alabama, to launch facilities at Cape Canaveral Air Force Station in Florida and Vandenberg Air Force Base in California.
The ship initially entered service as a maritime rocket carrier for the Boeing Corporation as the Delta Mariner.
Use of Delta Mariner was transferred to ULA after the company was created in 2006 to handle all US military launch services. ULA is a 50/50 joint venture created out of the rocket manufacturing and launch service businesses of Boeing and Lockheed Martin for their Delta and Atlas V launch vehicles, respectively. For ULA, the ship has transported the Atlas V, Delta IV and Delta II rockets under the Delta Mariner livery.
On September 27, 2019, ULA re-christened the vessel RocketShip in a ceremony at its factory in Decatur.