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Why return to the Moon before going to Mars?

Subject Matter Expert: John Connolly and Chuck Lloyd

Mankind has worshipped and studied the moon for centuries. Early Aztecs built a pyramid in Mexico for their moon “god/goddess.” Today, people still speak of “the man in the moon.” From Earth, people’s imaginations hoped for life on the moon, even thinking that there were “seas” or “maria” on the moon’s surface.

Racing to the moon initially drove space exploration during the 1960s and early 1970s. Between July 20, 1969 and December 14, 1972, twelve Apollo astronauts walked on the moon. Their total time on the moon equals slightly more than 3 days (80 hours, 32 minutes, 26 seconds.)

Few of us will forget Neil Armstrong, the first person to walk on the moon, and his now famous words, “That’s one small step for man; one giant leap for mankind.” But do you remember the most recent person to walk on the moon? Eugene Cernan took the last moonwalk of the Apollo Program, and his words remind us that there is still much to explore. “America’s challenge of today has forged man’s destiny of tomorrow.”

Since 1972, the United States and other countries have sent several robotic probes to study the moon. From the Apollo program and recent robotic studies, NASA scientists have learned much about the moon’s environment, terrain, and the possibility of water.

The moon’s temperatures range from very hot (+134° C/+273° F) to very cold (–153°C/–244° F). Its gravity is 1/6 Earth’s, making astronauts feel much lighter on the moon than on Earth. The moon has no atmosphere.

In 1996, NASA’s Clementine spacecraft collected data that indicated there was ice in the bottom of a crater near the moon’s South Pole. This area is permanently in shadow and very cold. In 1998, the Lunar Prospector probe gathered some exciting scientific data that showed even more ice at the North Pole. Based upon the data, scientists estimate that more than 5 trillion kilograms (about six billion tons) of water ice may be trapped in the shadows near the moon’s Polar Regions.

NASA’s next scheduled robotic lunar mission is the Lunar Reconnaissance Orbiter Mission. This spacecraft will search for water ice, look for potential resources in lunar dust, and map the lunar surface for potential landing sites. It will also study the effects of space radiation on samples identical to human tissue. All this information will help NASA return astronauts to safely work and live on the moon.

What we learn on the moon will help us plan for a crewed space mission to Mars, making it as safe and efficient as possible. There are many similarities between the moon and Mars. It is extremely cold on both. Gravity on both Mars and the moon is less than Earth’s gravity. The moon and Mars are both covered with a dust called regolith. Regolith is formed by constant bombardment of micrometeorites.

We think the moon and Mars both have water ice mixed within and trapped below their surfaces. Finding ways to collect and use water on the moon will help us learn to use Martian resources. We will also need to improve ways to recycle used water.

NASA’s current Vision for Space Exploration calls for “exploring Earth, moon, Mars, and beyond.” With only three days travel time from Earth, returning to the moon will help us learn how to prepare for long-term stays on other worlds. Additionally, living and working on the moon will provide opportunities to conduct new fundamental science studies. We’ll be learning how to “live off the land” by making oxygen and rocket propellants from the local materials, and we’ll be testing new technologies and operations. Living and working on the moon will be a test run for living and working on Mars and beyond.

Why return to the Moon before going to Mars? Newsbreak
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The following National Education Standards are addressed in this educational package.

Science (NSTA/NRC)
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