Operation Sandblast was the code name for the first submerged circumnavigation of the world, executed by the United States Navy nuclear-powered radar picket submarine USS Triton (SSRN-586) in 1960 under the command of Captain Edward L. Beach Jr.

The circumnavigation took place between February 24 and April 25, 1960, covering 26,723 nautical miles (49,491 km; 30,752 mi) over 60 days and 21 hours. The route began and ended at the St. Peter and Paul Rocks in the middle of the Atlantic Ocean near the Equator. During the voyage, Triton crossed the equator four times while maintaining an average speed of 18 knots (33 km/h; 21 mph). Triton's overall navigational track during Operation Sandblast generally followed that of the Spanish expedition that achieved the first circumnavigation of the world, started under the command of Portuguese explorer Ferdinand Magellan and completed by Spanish explorer Juan Sebastin Elcano from 1519 to 1522.

The initial impetus for Operation Sandblast was to increase American technological and scientific prestige before the May 1960 Paris Summit between President Dwight D. Eisenhower and Soviet Premier Nikita Khrushchev. It also provided a high-profile public demonstration of the capability of U.S. Navy nuclear-powered submarines to carry out long-range submerged operations independent of external support and undetected by hostile forces, presaging the initial deployment of the Navy's Polaris ballistic missile submarines later in 1960. Finally, Operation Sandblast gathered extensive oceanographic, hydrographic, gravimetric, geophysical, and psychological data during Triton's circumnavigation.

Official celebrations were cancelled for Operation Sandblast following the diplomatic furor arising from the 1960 U-2 incident in which a U-2 spy plane was shot down over the Soviet Union in early May. However, Triton did receive the Presidential Unit Citation with a special clasp in the form of a golden replica of the globe in recognition of the successful completion of its mission, and Captain Beach received the Legion of Merit for his role as Triton's commanding officer. In 1961, Beach received the Magellanic Premium from the American Philosophical Society, the United States' oldest and most prestigious scientific award in "recognition of his navigation of the U.S. submarine Triton around the globe."

USS Triton (SSRN/SSN-586) was a United States Navy radar picket nuclear submarine. In early 1960, it became the first vessel to execute a submerged circumnavigation of the Earth in Operation Sandblast. Triton accomplished this objective during her shakedown cruise while under the command of Captain Edward L. "Ned" Beach Jr. She was the only member of her class and had the distinction of being the only Western submarine powered by two nuclear reactors.

Triton was the second submarine and the fourth ship of the United States Navy to be named for the Greek god Triton. (The nomenclature being unusual in that U.S. Navy submarines, at that time, were usually named for fish.) At the time of her commissioning in 1959, Triton was the largest, most powerful, and most expensive submarine ever built at $109 million, excluding the cost of nuclear fuel and reactors ($968 million today).Triton's mission as a radar picket submarine was made obsolete after two years by the introduction of the carrier-based Grumman WF-2 Tracer airborne early warning aircraft. She was converted to an attack submarine in 1962 and became the flagship for the Commander, Submarine Forces, U.S. Atlantic Fleet (COMSUBLANT) in 1964. She was decommissioned in 1969, the first U.S. nuclear submarine to be taken out of service.

Triton's hull was moored at the St. Julien's Creek Annex of Norfolk Naval Shipyard in Portsmouth, Virginia as part of the reserve fleet until 1993, though she was struck from the Naval Vessel Register in 1986. In 1993, she was towed to Puget Sound Naval Shipyard to await the Nuclear Powered Ship and Submarine Recycling Program. The former Triton landed on the keel resting blocks in the drydock basin on 1 October 2007 to begin this recycling process, which was completed effective 30 November 2009. Triton's sail superstructure was saved from the recycling process and is now part of the USS Triton Submarine Memorial Park located on Port of Benton Boulevard in Richland, Washington.