On April 22, 1957, the company name was formally changed to The Martin Company.
Postwar efforts in aeronautics by the Martin Company included two unsuccessful prototype bombers, the XB-48 and the XB-51, the marginally successful AM Mauler, the successful B-57 Canberra tactical bombers, both the P5M Marlin and P6M SeaMaster seaplanes, and the Martin 4-0-4 twin-engine passenger airliner.
The Martin Company moved forward into the aerospace manufacturing business, and it produced the Vanguard rocket, which was used by the American space program as one of its first satellite booster rockets as part of Project Vanguard. The Vanguard was the first American space exploration rocket designed from scratch to be an orbital launch vehicle — rather than being a modified sounding rocket (like the Juno I) or a ballistic missile (like the U.S. Army's Redstone missile). Martin also designed and manufactured the huge and heavily armed Titan I and LGM-25C Titan II Intercontinental Ballistic Missiles (ICBMs). Martin Company of Orlando, Florida, was the prime contractor for the U.S. Army's Pershing missile.
The Martin Company was also one of two finalists for the Command and Service Modules of the Apollo Program. Unfortunately for Martin, NASA awarded the design and production contracts for these to the North American Aviation Corporation.
The Martin Company went further in the production of even larger booster rockets for the National Aeronautics and Space Administration and the U.S. Air Force with its Titan III series of over 100 rockets produced, including the Titan IIIA, the more-important Titan IIIC, and the Titan IIIE. Besides hundreds of Earth satellites, these rockets were essential for the sending to outer space of the two space probes of the Voyager Project to the outer planets the two space probes of the Viking Project to Mars, and the two Helios probes into low orbits around the Sun. (closer, even, than Mercury.)
Finally the U.S. Air Force required a booster rocket that could launch heavier satellites than either the Titan IIIE or the Space Shuttle. The Martin Company responded with its extremely large Titan IV series of rockets. When the Titan IV came into service, it could carry a heavier payload to orbit than any other rocket "except" for NASA's Saturn V rocket — which was no longer in production and thus was a machine from history. Besides its use by the Air Force to launch its sequence of very heavy reconnaissance satellites, one Titan IV, with a powerful Centaur rocket upper stage, was used to launch the heavy Cassini space probe to the planet Saturn in 1997. The Cassini probe has been in orbit around Saturn since 2004, successfully returning mountains of scientific data.
The halting of production of the Titan IV in 2004 brought to an end production of the last rocket able to carry a heavier payload than the Space Shuttle, which itself ended in 2011.
The Martin Company merged with the American-Marietta Corporation, a chemical products and construction materials manufacturer, in 1961 to form the Martin Marietta Corporation. In 1995, Martin Marietta, then the nation's 3rd-largest defense contractor, merged with the Lockheed Corporation, then the nation's second largest defense contractor, to form the Lockheed Martin Corporation, becoming the largest such company in the world.