constructed a military outpost there. The defence of the moon – despite the fact that at this point it had not even been visited by an unmanned probe – was considered as of paramount importance to the security of the United States.
The use of the base for Earth observation would also be valuable; large telescopes could be mounted on the Moon, and used for applications such as meteorology and military reconnaissance; both of these functions could be better accomplished from orbit, but digging into the Moon would provide more protection against attack. In addition, activities in near-Earth space could be monitored, vital if space was to become a new theatre of war. The establishment of an 'observation post in the heavens' was the primary objective of the program.
There were of course strong scientific possibilities. Though the nature of the base as an Army outpost, meant that military objectives were paramount, it was recognised that the base could be used to support the exploration of the moon; geological survey teams could roam around the landscape, and astronomers would have found it an ideal site for observation. (It may well have been in the back of the minds of many of the planners that an Army base on the moon could have served the same purposes as the Western forts, as outposts from which the growth of civilization could be encouraged.)
Construction work for the base was scheduled to begin in 1964; it would require more than a hundred Saturn launches to complete. These would be in two types; the then-planned ABMA Saturn booster was described as 'Saturn I', with an advanced 'Saturn II' to be developed later on. The first cargo would be delivered to the moon in 1965, with the base to become operational in late 1966.
The planning documents essentially describe the creation of an entire space program to support the base on the moon. An early step would be the construction of an equatorial launch pad, followed by the creation of a 24-hour communications network, as well as completing comprehensive maps of the moon in order to determine the ideal site for the base.
1964 would see a hive of activity focused on the space effort, with six lunar satellites, eight lunar soft landings, seven lunar circumnavigations, four orbital return missions, and fifteen operational trips for the build-up phase; it was estimated that the Saturn I would be used seventy-six times in this year, forty of which would be for Project Horizon.
Under this plan, the first man to land on the moon – a construction engineer, no doubt! - would have set foot on the surface in April 1965. He would have been the vanguard of a construction force, presumably consisting of workers from the Army Corps of Engineers, which would have spent the next eighteen months readying the base for occupancy. The base itself would operate with a task force of twelve men, and it was planned that forty Saturn launches would be used to supply the base in its first year.
Simply the numbers of launches involved illustrate the amazing scope of this project. In one year, this project would see more than twice the number of Saturn launches than actually took place . To call the engineering targets ambitious is an understatement, but it was assumed that a similar national effort to the Manhattan Project – a project that was foremost in the minds of many of the people preparing the plans for Project Horizon – would be used to place a military outpost on the moon.
As for the base itself, it would consist of the living quarters, powered by a pair of nuclear reactors and using a parabolic antenna to maintain communications with Earth. Defence against possible Soviet attack was provided for; a series of claymore mines, designed especially for puncturing spacesuits, would be deployed on the perimeter of the base, and Davy Crockett missiles (tipped with low-yield nuclear warheads) would also be employed for protection. Laboratories for studying biological