For over 50 years, NASA and its predecessor organizations have been planning missions to send humans to Mars. From the earliest concepts in the 1950s to more detailed studies in the 1960s and beyond, the red planet has captured the imagination of space exploration advocates who see it as the next logical step after the Moon. This article traces the history of Mars mission planning from 1950 to 2000, examining how the plans evolved based on increasing knowledge of Mars, technological progress, and the shifting political and cultural context of the Space Age.
Early Visions
In the early 1950s, German rocket pioneer Wernher von Braun, working for the U.S. Army, wrote a novel describing a large expedition to Mars. His plan envisioned a fleet of 10 ships carrying 70 crew members. Though infeasible with the technology of the time, von Braun’s vision helped popularize the idea of human missions to Mars.
In a series of articles in Collier’s magazine starting in 1952, von Braun laid out a more detailed plan, still on a grand scale but incorporating a space station as a staging base. These widely read articles captured the public imagination and established von Braun as the face of space exploration in America.
NASA Takes Up the Challenge
After NASA’s creation in 1958, the agency began studying Mars mission concepts in earnest. At Lewis Research Center in Ohio, engineers investigated nuclear-thermal and electric propulsion as a way to reduce spacecraft weight. They envisioned an ambitious mission with a 420-day round trip and a 40-day stay at Mars.
At Marshall Space Flight Center in Alabama, under von Braun’s leadership, the Future Projects Office conducted a series of studies called EMPIRE (Early Manned Planetary-Interplanetary Roundtrip Expeditions). These studies in the early 1960s examined various mission profiles, including flybys of Mars without landing.
Robotic Precursors and Changing Perceptions
The successful Mariner 4 Mars flyby in 1965 provided the first close-up images of the planet’s surface. These pictures revealed a cratered, seemingly lifeless world, much less hospitable than previously imagined. This dealt a blow to hopes for finding advanced Martian life and forced a reassessment of Mars mission plans.
Subsequent Mariner missions in 1969 reinforced this new view of Mars as a forbidding planet. The atmospheric density was found to be much lower than expected, meaning that landing spacecraft would need more propulsive power and that winged gliders would not be feasible.
Apogee of Mars Planning
Despite the Mariner findings, NASA continued to study ambitious Mars missions throughout the 1960s. The space agency envisioned the massive Saturn V rocket, developed for the Apollo lunar program, as the key to launching human expeditions to Mars.
In 1969, at the height of the Apollo program, NASA’s Space Task Group developed an integrated plan for the future of space exploration. It proposed a series of Mars expeditions in the 1980s, with the first landing in 1982. Wernher von Braun, in a presentation to the Space Task Group, outlined a plan to send two ships carrying six astronauts each. They would orbit Mars, send automated probes to collect samples, and land a crew of three for a 30 to 60 day stay.
However, political and public support for such an ambitious undertaking was lacking. The Vietnam War and domestic turmoil made an expensive Mars program untenable. President Nixon did not approve NASA’s sweeping vision, instead calling for a more measured approach focusing on a reusable Space Shuttle.
Waning Interest
In the 1970s, NASA’s Mars ambitions faded as the agency struggled to gain approval for the Space Shuttle program. A few studies continued at a low level, constrained by tight budgets. The last formal NASA Mars expedition study of this era, completed in 1971, acknowledged the dimming prospects for a human mission.
The Viking missions in 1976, which landed two spacecraft successfully on Mars, provided a wealth of new data. However, they found no clear signs of life, further diminishing the rationale for urgent human exploration. Mars mission advocates would have to wait until the 1980s for a resurgence of interest in the red planet.
Space Exploration Initiative
In 1989, on the 20th anniversary of the Apollo 11 Moon landing, President George H.W. Bush announced the Space Exploration Initiative (SEI). It called for completing Space Station Freedom, returning to the Moon, and then undertaking a human mission to Mars.
NASA’s “90-Day Study” in response to the SEI outlined an ambitious plan: a permanent Moon base by 2010 and a first human landing on Mars as early as 2015. However, the high cost estimates, exceeding $500 billion over 20-30 years, quickly led to the initiative’s demise in Congress.
The failure of the SEI demonstrated the difficulty of marshaling political and budgetary support for large-scale, multi-decade space projects with distant payoffs. The experience would shape NASA’s approach to Mars planning in the 1990s.
Design Reference Mission
Chastened by the SEI’s collapse, NASA took a more incremental approach in the 1990s. The agency focused on robotic exploration through the Mars Surveyor program, while also refining its human mission concepts.
In 1997, NASA released the first version of its Design Reference Mission (DRM) for human exploration of Mars. The DRM represented a shift in philosophy from the SEI’s massive, long-term approach. Instead, it outlined a more focused, achievable first mission that could be a precursor to long-term exploration and settlement.
The DRM baselined a crew of six traveling to Mars on a “split mission” profile, with some supplies pre-positioned by robotic missions. The first human landing would occur around 2014, with a surface stay of 500-600 days. Nuclear thermal propulsion was identified as a key enabling technology.
Subsequent iterations of the DRM refined the concept and pushed out the schedule, but retained the fundamental approach of a initial landing mission as a steppingstone to future expeditions. By 2000, the first human mission to Mars was envisioned no earlier than 2020-2025.
Conclusion
The first half-century of Mars mission planning reveals a remarkable consistency of vision tempered by the realities of politics and scientific discovery. While the earliest plans were grandiose and infeasible, later studies became increasingly sophisticated and grounded. Throughout this history, Mars has remained the ultimate goal for many space exploration advocates, even as the rationale has shifted from finding Martian civilizations to understanding the planet’s geology and potential for life.
As we enter the 21st century, the dream of human footsteps on Mars appears tantalizingly close, yet still elusive. Robotic explorers have revealed the red planet in unprecedented detail, uncovering past and present water, complex geology, and possible niches for microbial life. New technologies, such as nuclear propulsion and in-situ resource utilization, offer promising solutions to the immense challenge of transporting humans to Mars and sustaining them there.
However, the greatest hurdles to a human Mars mission remain unchanged from the 1960s: the need for unwavering political support and ample funding over many years. In a time of competing priorities on Earth, mustering the national will to send humans to another planet is no small task.
Yet the imperative to explore remains strong. Mars beckons as a scientific frontier, a challenge to our technological prowess, and a potential second home for humanity. The history of Mars mission planning reminds us that great visions often take decades to come to fruition, buffeted by setbacks and shaped by new knowledge. As we continue to reach for the red planet, we stand on the shoulders of the pioneers who first charted the course.
