Project Rover

Project Rover was an American project to develop a nuclear thermal rocket. The program ran at the Los Alamos Scientific Laboratory from 1955 through 1972 and involved the Atomic Energy Commission, and NASA. The project was managed by the Space Nuclear Propulsion Office.

Nuclear reactors for the Rover program were built at the Lab's Technical Area 18 (TA-18), also known as Pajarito Site. The reactors were tested at very low power and subsequently shipped to Jackass Flats at the Nevada Test Site. Testing of fuel elements and other materials science was done by N-Division in Los Alamos at TA-46 using various ovens and later the Nuclear Furnace. Parallel fuel rod development took place off-site at Rocky Flats.

Project Rover could be divided into three phases: Kiwi, between 1955 and 1964, Phoebus, taking place between 1964 and 1969, and Pewee, taking place between 1969 and the project's cancellation along with the cancellation of the NERVA rocket at the end of 1972. Kiwi and Phoebus were large reactors; Pewee 1 and Pewee 2 were much smaller and they conformed to the smaller budget available after 1968. Both Kiwi and Phoebus became part of the NERVA program.

As early as 1942, Enrico Fermi and his colleagues in the Manhattan Project discussed the use of nuclear energy to propel aircraft. In 1945, at the suggestion of Manhattan Project participants, the Air Force Scientific Advisory Board (SAB) studied the potential use of nuclear power for rocket propulsion. SAB recommended no action from this study.

In 1944, in the later days of Project Manhattan District, Stanislaw Ulam and Frederic de Hoffman published speculative ideas regarding alternate applications of nuclear energy. These ideas included the possible use of bombs to push missiles. At about the same time, T.F. Dixon and H.P. Yockey at North American Aviation published a paper discussing the use of a nuclear-powered heat exchanger to heat hydrogen or methane, concluding that nuclear power was sufficiently promising to deserve some investigation.

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