The Northrop SM-62 Snark was an specialised intercontinental missile with a nuclear warhead briefly operated by the US Strategic Air Command from 1958 until 1961.

Basically an unmanned aircraft, the jet engined 20.5 m long device had a top speed of 650 mph and a maximum range of 5,500 nm. The complex stellar navigation based guidance system gave a claimed CEP of 8,000 ft.

The Snark was an air-breathing design, launched from a light platform by two rocket booster engines it would then switch to an internal jet engine for the remainder of its flight. The jet was a Pratt and Whitney J57, the first 10,000 lb thrust design, also used in the early B-52 and the F-100. Lacking a horizontal tail surface and using elevons as the main control surfaces the missile flew an unusual nose high aspect during level flight. During the final phase of flight the nuclear warhead would detach and follow a ballistic trajectory to the target.

It was developed to offer a nuclear threat to the Soviet Union at a time when ICBMs were still in development. Work on the project had begun in 1946, initially there were two missiles - a subsonic design (the MX775A Snark) and a supersonic design (the MX775B Boojum). Budget reductions threatened the project in its first year but the personal intervention of Jack Northrop with Carl Spaatz saved the project. Despite this funding was low and the program was dogged by requirement changes. The expected due date of 1953 passed with the design still in testing and SAC was becoming less enthusiastic. In 1955 Eisenhower ordered top priority to the ICBM and associated missile programs.

Despite considerable difficulties with the missile and military reservations work continued. In 1957 tests the missile had an average CEP of 17 nm and the most accurate test of 1958 fell 4 nm short. The design was also notoriously unreliable with the majority of test missile suffering mechanical failure thousands of miles before reaching the target area. The reduced operating altitude, from 150,000 ft to 55,000 ft, and the inability of the missile to undertake evasive manoeuvres were also cited against it.

In January 1958 SAC began accepting delivery of operational missiles to Patrick AFB in Florida for training and in 1959 the 702nd Strategic Missile Wing was formed. The 702nd was not declared operational until February 1961 and shortly thereafter in June 1961 the new president scrapped the entire project.

The missile name is from the Lewis Carroll poem The Hunting of the Snark.