USNS Sirius (T-AFS 8) was a Sirius-class combat stores ship of the United States Navy, named for Sirius (α Can. Maj.), the brightest visible star.
Sirius was built by Swan Hunter & Wigham Richardson for the Royal Navy. Laid down in 1965, she was launched in 1966 from Wallsend as RFA Lyness (A339). She was transferred from the British Royal Fleet Auxiliary to the U.S. Navy's Military Sealift Command in 1981.
Sirius was deactivated and struck from the Naval Vessel Register in 2005 and given to the U.S. Department of Transportation’s Maritime Administration (MARAD), then assigned to Texas Maritime Academy under an agreement that it can be activated by MARAD at any time. During the fall of 2005, the Sirius served in New Orleans for Katrina relief, from September 10 until November 29 and at Lake Charles, LA for Rita relief until March 2. Because of its extended relief effort the Sirius was unable to undergo a refit in 2006 to adapt its new role as a training vessel and comply with U.S. Coast Guard safety standards. Because the Sirius had not undergone a refit, it could not be formally commissioned as the USTS Texas Clipper III nor could it be used for summer training cruises. In the winter of 2009 the US Coast Guard ruled that the Sirius was unfit for training and was prepared for decommissioning while the school looked for a new training ship. On June 25, 2009, the Sirius was returned to the U.S. Maritime Administration.