Moon base, landing on Mars: NASA’s rejected plans from the 1960s and 1970s
Introduction
NASA was founded as a response to early Soviet space successes, more specifically the launch of Sputnik. Its mission to land a man on the Moon came as a response to Yuri Gagarin’s flight on Vostok 1. The Apollo program was never very popular with the American public, except the brief period between Apollo 8 and Apollo 11, that is the first half of 1969. After the Apollo 13 mishap public support evaporated and NASA decided to turn the focus of the space program towards the Earth and towards reducing space access cost. The Space Shuttle today tends to be seen as a failure and the wrong step, though being today only six years after the last flight it is hard to form yet an objective opinion, we are too close to judge. According to public polls the American public considered the moon landings great achievements in the 1980s, after some 15 years had passed. The Shuttle did send more people to space than any other spacecraft, proved in the negative several notions such as that it is cheaper and easier to refurbish and refit a satellite as opposed to launching a replacement (think cost and ease of Hubble Space Telescope refit) or that it was possible to save money through a complicated reusable spacecraft, at least one built with 1970’s technology. Before though Nixon decided that after Apollo the Shuttle was to follow, many at NASA believed that further manned exploration of the Solar System was to be pursued and drew up plans for it. This planning had already begun when it became obvious that after some of the early Apollo hardware had been developed, staff would have to be laid off unless further work was in the pipeline, even before the Moon landing. NASA started again looking at exploration beyond Low Earth Orbit after the Space Station was authorized, again the idea being to look two steps down the road. This is an essay on the NASA plans to expand presence on the Moon and land on Mars, most associated with the Apollo Applications program, before it became obvious that Shuttle — Station was to consume NASA’s resources for decades to come. I am greatly indebted to David Portree’s blog, his Mars plan book and to several relevant Wikipedia pages; I am not an archivist able to dig into the available documents.
Space Stations in Earth orbit
In the end this is the only part of the plans that came to fruition, both originally in the form of Skylab and more recently in the heavily modified form of the International Space Station. The first plans of the Apollo Applications Program depended on the Wet Workshop concept: Take the upper stage of a Saturn V, send it in orbit/to the Moon/to Mars and Venus, move into the now vacated oxygen tanks and use them as living quarters and laboratory space for the astronauts. In the end only Skylab materialized of the whole Apollo Applications program and then as a dry workshop: it was based on a Saturn I upper stage launched on top of a Saturn V that was already preconfigured as a Space Station at launch rather than have astronauts do a retrofit while in orbit. The Apollo Applications Program originally envisioned that after Skylab, which after all was a temporary space station to learn how one works, it would be followed up by an organic development of similar space station, capable of resupply, prototypes of what was to be send beyond earth orbit, similar to Salyut. Nixon in the end allowed Skylab to launch in exchange for cancelling two moon landing and because it was obvious that between the last moon landing and the first shuttle launch there would be too big a gap. Skylab remained a dead end for American spaceflight, up until the ISS. The Soviet approach of slow and steady, with first generation Salyut followed by the resuppliable second generation Salyut 6 and 7 followed by the modular upgradable Mir and eventually, after the merger with Freedom, by the ISS won out. Then again though, through the merger with the Russian space program the US leapfrogged three steps on making a space station, so the long wait was not a total loss. Also NASA learned about long term space stays by sending astronauts to Mir, which it helped maintain during the 1990s.
The four step program to build a lunar base
At a time when it was not obvious how many trips to the moon the Apollo program was to consist of and if it would be extended, NASA drew up plans to continue to its logical extension: a permanent or at least semi-permanent base on the Moon. The first step, which corresponds to Apollo 11, 12 and 14, were simple excursions on the moon’s surface, with astronauts leaving the lunar lander to explore on foot their surroundings. Second step, which corresponds to Apollo 15 to 17 was to use the extended Lunar Module, which in the end was built as the Block 3 version of the Lunar Module, to stay longer on the Moon and the Lunar Rover to explore further away from the landing site. Third stage was a 28 day lunar orbital survey mission, which would not land but have astronauts take high resolution imagery of the lunar surface for ground truthing. This part was not implemented, but we can say that lunar missions from the 1990s on, such as the Lunar Reconnaissance Orbiter, have accomplished the lunar science part. If the 28 day mission had a space medicine part such as how being outside the Earth’s magnetic field and its protection from cosmic rays affects the human body, it has not been completed. Considering the time of the proposal and the sort of risks taken during Apollo, this sort of biological experiment was most likely not part of the proposal. The fourth step would have been sending down a lunar shelter with food, supplies and equipment that astronauts would inhabit, rather than just the Lunar Module. The first plans envisioned a Lunar Module without an ascent stage, a modified version of the LM truck (which also was never built). It could offer shelter for a 14 earth day long lunar day. In later plans a wet workshop would be soft landed on the Moon, and that could be at least semi-permanent. Beginning with Apollo 13 NASA did crash the upper stage of Saturn V to create artificial earthquakes for the seismometers it left on previous missions, thus soft landing it was not out of reach. Considering the political and financial capital it took to get the International Space Station in Earth orbit and how many resources its operation is consuming, it is not surprising that lunar surface bases have never moved beyond paper studies. The current NASA plan calls for the Deep Space Gateway, a scaled down (compared to the ISS) partially crewed space station in lunar orbit, that can be used as a stepping stone to land on the moon and as a prototype for an interplanetary spacecraft to Mars. One of the contractors of the initial studies, Lockheed Martin, will use a space ISS logistics module as a ground prototype for its plan. The other contractors of the competition intend to follow. This alas is the farthest that lunar colonization plans have advanced in the 48 years since Apollo 11.
Manned Venus (and Mars) flybys in the 1970s
The Moon is an interesting place, but there was the will to push the frontier outward after the Moon landings. Manned Venus flyby was repeatedly proposed and studied as the next step by several different NASA centers and advisors. A spacecraft, originally based on the wet workshop concept, though eventually several other more conventional concepts were studied, would be sent on a free return trajectory to Venus. The trip would last between one and two years, depending on the trajectory and it would allow systems testing and several investigations. In some of the trajectories studied the mission included a flyby of Mars, often on the way back to Earth. While Mars flyby was always to be the next rung of the same ladder of exploration, Venus simply was easier and closer to reach. Hardware wise no consensus was reached, the lightest concept called for the use of a single Saturn V on top of which, where the Lunar Module was stored in Apollo missions, would be a more permanent habitat. Other concepts went as far using three rockets, one with the living space, one with an uprated for better reentry Apollo Command Module and one with fuel to send the stack on its orbit. Over time the mission was also fleshed out with scientific investigations. Astronauts would have a telescope to study Venus, Mercury and the sun both during the trip and during the 20 hour encounter itself. Some of the concepts included a radar for mapping Venus’ surface. Several automated probes would be included to be dropped on Venus’ atmosphere. Biological investigations would be carried out on the astronauts on how they responded to the space environment, e.g. microgravity and radiation, similar to those carried since on earth orbiting space stations. Still, the mission package was considered rather weak. If the emphasis was on biological science, the same investigations could and was carried out in Earth orbit, other than the effects of cosmic radiation. If the emphasis was on Venus science, the investigations could be carried out more cheaply and safely with unmanned spacecraft. Pioneer Venus did drop four probes on Venus and Magellan carried full radar mapping of the Venus surface. In any case, with the exception of variations that included an orbit insertion (for up to 30 days in orbit), the entire Venus encounter was to last about 20 hours. Generally a Venus mission made very little sense on its own except as a stepping stone to somewhere else, such as Mars.
Mars landing in the 1980s, preferably 1988
Every fifteen year the Earth Mars Hohmann transfer orbit is especially advantageous energetically. It takes less fuel to send the same payload than on the typical 26 month opposition. 1988 was one of those years, as was 2003 when the Mars Exploration Rovers Spirit and Opportunity were launched along with ESA’s Mars Express and so will 2018, when InSIGHT is planned to be launched. For the 2033 conjunction NASA actually plans a crewed flyby mission, though they have admitted that to make that happen Congress needs to appropriate more funding. In Apollo era planning after the 1970s Venus and Mars flybys, the 1980s were to lead to a surface landing. NASA never quite put down a year, after all we are talking about planning that took place in the 1960s, but it is natural to assume it to be 1988. NASA Mars planning was separate from the Apollo project, but eventually it did try to leverage Apollo technology and hardware rather than reinvent the wheel. Considering the inherent inefficiency of chemical rocket engines, and in order to reward Congressional allies, NASA funded active development on Nuclear Thermal Engines as a power source for Martian spacecraft throughout the 1960s up to 1972. This was not though the only propulsion plan; there were also chemical rocket plans, especially those that were a followed to the fully conventional Manned Venus Flyby missions. Some of the studies calculated optimal Mars trajectories to select proper take off time and one included a trajectory that encountered asteroid 433 Eros. The first NASA Mars plans begun before Mariner 4 encountered Mars in 1965 and gave good information on its actual conditions. Based on Earth based observations, they actually planned airplane style landing for the spacecraft or even spacecraft fleet. While the rest of the Apollo Applications Program except Skylab was cancelled in FY1968, NASA administrator George Low decided to further develop and refine plans for Mars which were presented among the various options given to Nixon in 1972. Congress had already signaled in hearings in 1968 that it was not interested in sending a person to Mars if the Moon landing succeeded and came before the Soviet landing. Nixon would have preferred to abolish NASA after Apollo and it was Congressional and public pressure that stopped him. In the end he chose to pursue the Space Shuttle which was the cheapest option, gave to Congress the lowest cost estimate and might have even hoped that the program would explode budget wise, taking down NASA with it. The Mars plans of 1972 today form a link in the large collection of Mars plans that have been proposed over the years. A systematic bureaucratic program for Mars exploration, rather than a series of ad hoc proposal given by various centers and contractors sporadically, was to form only with president George H.W. Bush’s Space Exploration Initiative. While the SEI proved stillborn, the Design Reference Mission it brought out has continued existing as a process, with the current iteration being DRM 5 which follows George W Bush’s Vision for Space Exploration proposed architecture.
Conclusion
In principle adoption of the Space Shuttle did not have to mean abandonment of Deep Space Exploration plans. After all with cheap access to space, bringing them to fruition simply meant assembling components in space before launching them in their trajectory. For that matter there were several pre Challenger plans that used this approach. Abandoning though the Apollo hardware meant that several capabilities it afforded were no longer available, most notably the lifting power of the Saturn V. The baton of the leading edge of space exploration passed to the robotic part of the space program, starting with the Vikings in 1975. The human spaceflight program, as it was renamed after NASA started recruiting female astronauts, at first focused into the Space Shuttle which tried to be all things for all people. Then the Space Station was built, though it suffered several near death experiences until assembly begun, not due to incompetence but rather of divergent priorities the station tried to meet. Some plans wanted the Space Station as a Spacedock, a place where spacecraft to the great beyond would be launched after being assembled in pieces. Other plans wanted a science lab pure and simple. In the end Congress authorized the Space Station because of its commercial appeal, although 15 years after assembly begun the ISS’ main commercial function has been to launch cubesats. Commercial research involving humans proved time consuming and complicated bureaucratically. NASA’s plans to move beyond Low Earth Orbit moved into high gear after the Columbia accident, as a follow up to the soon to be completed (though it took a few more years) space station and as an escape from the Columbia tragedy. The Apollo on Steroids approach of the George W Bush Vision for Space Exploration in the end blew up, by its cancellation in 2010 it was already consuming 60% of NASA’s budget and it was nowhere hear producing new flight hardware. Its failure though coincided with the emergence of NewSpace, companies that promise to do what the government and traditional contractors do better and for a fraction of the cost, while taking more risk. Today there is an ever larger series of proposals for missions beyond low earth orbit, both from established contractors and NewSpace companies while there is also the Space Launch System/Orion system that feels at times in search of a goal. Mars is still the horizon goal of space exploration, but often it feels farther away than where it was in the 1960s when the plans outlined were originally proposed while Saturn V was undergoing its first testing.