In 1959 the Soviet Luna 2 probe missed the Aristarchus crater and landed on the other side of the Mare Imbrium. Other Luna missions placed orbiters around the Moon, equipped with cameras to search for signs of human activity.
Meanwhile, the US Ranger program had yielded a few images of the lunar surface before its probes crashed, but none showed anything that looked like a moonbase. The Ranger program was not an unqualified success. Ranger 1 and Ranger 2 failed to launch; Ranger 3 to Ranger 5 all failed in flight, with two missing the Moon completely; and Ranger 6 suffered a camera failure that may have been due to a hit from a Röntgenkanone or similar weapon. Improved shielding on the last three Ranger probes allowed them to transmit detailed images back to Earth, but their usefulness was limited by the fact that they were designed to crash into the lunar surface.
The Lunar Orbiter program of 1966–67 was more successfuclass="underline" in five missions it mapped 99 percent of the Moon’s surface with a resolution of 200 feet or better, and provided confirmation of man-made structures in the Aristarchus crater.
This information was used in planning the Surveyor series of landers, which transmitted clearer images of the Walhalla base before landing in widely scattered locations from June 1966 through January 1968. This deliberate dispersal of landing sites had two objectives: to make it harder for Nazi scientists to recover the landers and analyze their technology; and to preserve, if possible, the illusion that they were part of an innocent scientific mission by a United States that had no idea of the Walhalla base’s existence.
In regard to the second objective, at least, the strategy was a failure: spies inside von Braun’s staff at NASA were already feeding information to Walhalla, keeping the Black Sun fully informed about American progress on the hunt for the moonbase. Information leaked by these agents enabled Walhalla to shoot down Surveyor 2 and Surveyor 4 without American knowledge: from the NASA control center, the effects of a KSK hit were impossible to distinguish from a malfunction in the landers’ propulsion systems.
While the American Moon program was conducted openly after Kennedy’s pronouncement in 1961, its Soviet counterpart was kept secret, and its existence was even denied. The Russians did not want their rivals to know how close they were to launching a manned Moon mission: their thinking was that the Americans would not rush so long as they thought they were ahead, giving the Soviet Union time to develop superior technology. Also, according to documents declassified in the glasnost era of the 1980s, it was felt that by openly declaring their progress in the Moon Race the Americans made themselves a more prominent target for any Nazi reprisals.
The whole world watched when astronaut Neil Armstrong stepped onto the Moon in 1969, but the heart of the Apollo 11 mission was taking place 60 nautical miles above, where Michael Collins, in the command module Columbia, was continuing the reconnaissance work undertaken by previous Apollo missions to photograph the Walhalla base. Since Apollo 8 had first orbited the Moon in late December of 1968, NASA had photographed the base with ever more powerful cameras to assess its defensive capabilities. Back on Earth, planning experts analyzed the photographs and film brought back from the Apollo orbiters and developed an assault strategy.
While the Apollo missions were putting boots on the ground and developing expertise for a planned ground assault, the Russian plan took a different approach. The Zond series of missions are still described as planned Moon landings, but they secretly aimed to create an orbiting base assembled from Soyuz 7K-L1 components, which would be used to knock out the Walhalla base’s defenses from long range before dropping troops to conquer it. As will be seen, though, this plan did not reach completion.
In parallel with their early satellite programs, the United States and the Soviet Union both began planning moonbases of their own, with the intention of taking the war to the Moon and extinguishing the Nazi threat once and for all. The effort was also spurred by growing Cold War tensions: whoever controlled the Moon, it was thought, would also control the Earth.
The Black Sun response to the Apollo landings came in 1970 with the attack on Apollo 13. When the spacecraft came within five and a half hours of lunar orbit, it was struck by a KSK energy beam that caused an oxygen tank to explode, severely damaging the Service Module and causing the mission to be aborted.
For three tense days, the world watched as the crew struggled to survive and return to Earth in their crippled spacecraft, believing American press releases that wrote the explosion off as an accident. In American military circles, though, it was well known that this was an attack, and a response was urgently needed.
Apollo 13 was the last of the program actually to be launched. The remaining four missions were simulated in the Nevada desert while the United States secretly switched its efforts to developing von Braun’s proposed moonbase in order to mount an assault on Walhalla and end the Nazi threat once and for all.
In 1958–59, both the US Army and US Air Force commissioned plans to establish a manned base on the Moon by the mid-1960s.
Project Lunex, the Air Force plan, used a one-piece lander and return vehicle that looked something like the Space Shuttle of the late 20th century. It planned to establish a permanent American presence on the Moon by 1968. Officially, the project was scrapped over crew safety concerns, and because the lander would require an even larger rocket than the Saturn V to take it to the Moon. However, various aspects of the Lunex designs were developed as classified projects at the famed Lockheed-Martin “Skunk Works” and saw service as components of Project Horizon.
Project Horizon was conceived by Wernher von Braun’s team at the Army Ballistic Missile Agency, and aimed to establish a manned moonbase by 1967. Saturn-A boosters would be used to lift components into orbit, where they would be assembled at a space station. The project was examined at the highest levels, and then shelved in favor of the Apollo program.
After the attack on Apollo 13, however, priorities changed. After a total of 40 classified launches in 1970, the so-called “lunar shuttle” was complete, and starting in January 1971 it landed structural components on the southwestern edge of the Mare Imbrium, a comfortable distance from the Walhalla base. A defensive perimeter was set up immediately, consisting of low-yield Davy Crockett nuclear rockets and Claymore mines adapted to pierce space suits. The first phase of construction was complete by April and over the following 18 months a large complement of trained volunteers from every elite branch of the US military was secretly moved in.