USS Canopus (AS-34) was a Simon Lake-class submarine tender of the United States Navy, operational from 1965 to 1994. The vessel was used to repair and refit submarine-launched Polaris nuclear-armed ballistic missiles and the submarines that deployed with them. The vessel primarily served US naval bases on the US Atlantic Coast and in Europe. In 1969, the ship was overhauled to maintain the new Poseidon Missile Systems. Taken out of service in 1995, the US Navy's intent to have the ship broken up for scrap in the United Kingdom was controversial. By 2010 demolition had been completed.