Mars Bases

A Mars base could be the key to making Mars part of humanity's future. Explorers at a base could explore Mars for years or even decades. This is significant because while Mars has only half Earth's diameter, it has as much surface area to explore as Earth has land area. A Mars base might also serve as a stepping-stone to a permanent Mars settlement. Mars is a desirable settlement target because it is the planet in the solar system most like Earth.

Types of Bases

The form that the first Mars base will take will depend on its ultimate purpose. If established only for brief use with specific objectives in mind, it might resemble a temporary base camp set up to scale Mt. Everest. Alternatively, it might be established for long-term scientific exploration, like McMurdo Base in Antarctica. A base might also be intended as a nucleus around which permanent Mars settlement could grow, much as Jamestown, Virginia, was for the English who settled North America in the early seventeenth century.

In old Mars plans, piloted landing missions, each lasting less than a month, started human exploration of Mars, and any form of base came only later. The Mars exploration plan favored today by the National Aeronautics and Space Administration (NASA), however, encourages establishment of a temporary base camp on Mars on the first expedition. In NASA's plan, spacecraft use a six-month, low-energy path to travel to Mars. The explorers must then wait at Mars for about 500 days while Earth and Mars move into position so the explorers' spacecraft can follow a six-month, low-energy path home to Earth. This strategy slashes the amount of rocket propellant needed, which saves money—less propellant means fewer expensive rockets are needed to launch the Mars mission into space. If NASA's Mars plan becomes the basis for future Mars expeditions, the astronauts are likely to spend most of their time at Mars on the surface, where they can dig in for protection from radiation and explore as much as possible.

If settlement is the ultimate goal, the base will serve as a "kindergarten" where humanity can learn about settling another planet. Researchers at the base will test human reactions to long exposure to Mars conditions. It is not known, for example, whether humans can survive indefinitely in Mars gravity, which is only one-third as strong as Earth gravity. The base will also develop settlement technologies. For a Mars settlement to be truly permanent, it will need to use Martian resources to sustain itself and grow. The base might, for instance, experiment with processing Mars dirt so it can be used to grow food plants in pressurized greenhouses. Researchers will also experiment with making fuel for surface and air vehicles and with manufacturing building materials.

Building a Mars Base

Setting up the base will be a step-by-step process. The first step will be to gather data about Mars so that a base site can be selected. Current robotic missions are providing initial data that might eventually be used for base site selection. At minimum, the site must be accessible by spacecraft, with flat places to land, and scientifically interesting sites should be located nearby. If meant for a long-term base or a permanent settlement, the site should be near useful resources, such as underground water or ice, geothermal heat sources, wind for windmills, and latitudes where solar energy can be used year-round. The base should be in a relatively warm area, not prone to dust devils (small whirlwinds of dust) or seasonal dust storms. It might be established on Mars' northern plains or in the southern hemispheric Hellas basin, both places where low altitude means that air pressure is relatively high (though even in such low-lying places it is still barely 1 percent of Earth sea-level pressure). High air pressure means that spacecraft can make fuel-saving parachute-assisted landings and that industrial processes using Martian air as a resource can be more efficient.

The next step will be to build the base. To start, modules built on Earth might land at the chosen site to form a start-up base. In 1965 German-born American rocket pioneer Wernher von Braun described a plan for a "little village" on Mars made up of crew and cargo landers based on Apollo program technology. The second Case for Mars conference, in 1984, envisioned a similar start-up strategy—cargo landers based on space shuttle and space station technology would be tipped on their sides to serve as living space.

A temporary base camp might not progress beyond this stage. If, however, the base is meant for the long term or as a settlement nucleus, the astronauts will eventually need to build large, complex structures to supplement modules shipped from Earth. At first, they will probably use prefabricated parts made on Earth. A Mars blimp hangar, for example, would be too large to ship from Earth in one piece, so it would have to be shipped in pieces and assembled on Mars. As new construction equipment arrives from Earth and experience with living on Mars increases, the explorers might begin building using Martian materials. As the Mars explorers become Mars settlers, they might dig tunnels into cliff faces, then progress to erecting clear plastic "tents" over craters and valleys, turning them into huge greenhouses.

Will We Build a Base on Mars?

These plans assume that we will send people to Mars, and that we will decide to establish a Mars base. History shows that, just because a new world awaits us, it does not follow that we will explore it. Apollo was not followed by a lunar base, even though much remains to be explored on the Moon. If there is life on Mars, we might not build a base—or, indeed, land humans—because to do so would contaminate the planet and possibly destroy its unique biota. We might instead settle worlds without life, such as Earth's Moon or the asteroids. Alternatively, if Mars is lifeless, a base could become life's first foothold on the planet. In time, Mars settlers might begin experiments aimed at remaking Mars' environment—a process called terraforming—so it can support plants and animals from Earth.

see also Earth—Why Leave? (volume 4); Food Production (volume 4); Habitats (volume 3); Human Missions to Mars (volume 3); Living on Other Worlds (volume 4); Lunar Bases (volume 4); Mars (volume 2); Mars Direct (volume 4); Mars Missions (volume 4); Power, Methods of Generating (volume 4); Resource Utilization (volume 4); Scientific Research (volume 4); Settlements (volume 4); Space Industries (volume 4); Terraforming (volume 4).

David S. F. Portree

Bibliography

Hoffman, Stephen J., and David I. Kaplan, eds. Human Exploration of Mars: The Reference Mission of the NASA Mars Exploration Study Team. Houston, TX: NASA Lyndon B. Johnson Space Center, 1997.

Portree, David S. F. Humans to Mars: Fifty Years of Mission Planning, 1950-2000. Washington, DC: NASA History Office, 2001.

Robinson, Kim Stanley. Red Mars. New York: Bantam Books, 1993.

von Braun, Wernher. "The Next Twenty Years of Interplanetary Exploration."Astronautics and Aeronautics 3, no. 11 (November 1965):24-34.

Welch, S. M., and C. R. Stoker, eds. The Case for Mars: Concept Development for a Mars Research Station. Boulder, CO: Boulder Center for Science and Policy, 1986.

Zubrin, Robert, with Richard Wagner. The Case for Mars: The Plan to Settle the Red Planet and Why We Must. New York: Free Press, 1996.

Internet Resources

Hoffman, Stephen J., and David I. Kaplan, eds. "Human Exploration of Mars: The Reference Mission of the NASA Mars Exploration Study Team." 1997. NASA, Lyndon B. Johnson Space Center. <http://www-sn.jsc.nasa.gov/PlanetaryMissions/EXLibrary/docs/MarsRef/contents.htm>.