"While going to the Moon may represent a more interesting activity for NASA's human spaceflight program than flying up and down repeatedly to low Earth orbit, it is nevertheless not the right goal for the space agency. Since the conclusion of the Apollo missions more than 3 decades ago, Mars is the challenge that has been staring NASA in the face. Mars, not the Moon, is the Rosetta Stone that will tell us the truth about the potential prevalence and diversity of life in the universe. And Mars, because of its richness in resources, - containing not only plentiful supplies of water, but carbon, nitrogen, and all the other substances needed for life and industry as well - is the nearest place where humans can settle, and thus is Rosetta Stone that will tell us our fate; whether we shall be restricted to one world or have the prospect before us of an open frontier as a multi-planet species.

"For the coming age of space exploration, Mars compares to the Moon as North America compared to Greenland in the previous age of maritime exploration. Greenland was closer to Europe, and Europeans reached it first, but it was too barren to sustain substantial permanent settlement. In contrast, North America was a place where a new branch of human civilization could be born. The Moon is a barren island in the ocean of space; Mars is a New World. Mars is where the challenge is, it is where the science is, it is where the future is. That is why Mars should be our goal."