As world history illustrates, humans are compelled to discover new frontiers. Our exploration of the space frontier has already begun. Robotic missions and new technology are the first steps toward expanding human presence in the solar system. Human missions to the Moon, Mars and beyond may become a reality in the 21st century, and NASA is leading the way.

The world's attention is focused on the exploration of the solar system more strongly now than ever before. The discovery of possible ancient life on Mars and the Pathfinder examinations are credited with much of that attention.

The rationale for exploring and settling space mirrors the spirit that has compelled explorers through the ages.

NASA's mission to explore continues as we build a foundation of technology, experience, and scientific knowledge. During the first decades of the 21st century, explorers from Earth could set foot on the Moon and Mars and expand the human frontier.