On the Cover: Humans have walked on the surface of only one world besides their own—the Moon. Someday we will return to the Moon, visiting our neighbouring world, Mars, and investigate asteroids that pass near Earth. In this issue we remember those first steps on the Moon and look forward to new journeys to other worlds.
4 Visions of 2010: Human Missions to Mars, the Moon, and the Asteroids: Louis D. Friedman looks to the future.
7 Looking Spaceward: Life, Work and Leisure...Out There: Arnauld Nicogossian discusses how to protect humans as we prepare for permanent life in space.
10 Living on the Moon: James D. Burke explains aspects of the adventure of humans returning to the Moon.
15 Returning to the Moon: Apollo 17 astronaut Harrison Schmitt tells us why we are going back to the Moon—and beyond, to Mars.
16 The Case for Mars: Christopher P. McKay, the original Mars Underground leader, discusses some of the serious plans and possibilities for Mars as a future site of human habitation.
14 News & Reviews World's Largest Telescope; mysterious Mercury.
20 World Watch Comet Halley armada.
21 Society Notes The universe unfolding; Project Sentinel continues.