On the Cover: A flat plain, probably formed by the repetitive eruption of thin, low-viscosity sulfur, covers the south pole of Io. The dark circular features are calderas formed by such eruptions. The calderas seen in this <i>Voyager</i> image are filled with either liquid sulfur at moderate temperatures or solid, chilled deposits of originally high-temperature sulfur.
4 A Talk with Hans Mark: Louis Friedman sits down with NASA's Deputy Director.
6 Comments on the Crisis in Planetary Explortion: Carl Sagan looks at the state of space exploration, and what Congress and The Planetary Society can do.
8 A Talk with Eugene Levy: Louis Friedman talks with Levy about the future of space exploration.
10 Detour Assists Galileo Mission: Louis Friedman explains how a discovery made eight years ago is helping keep the Galileo mission to Jupiter alive.
17 Arabian Astronomy: Director of the Smithsonian's Center for Earth and Planetary Studies at the National Air and Space Museum Farouk El-Baz explains discusses the birth of astronomy as a science.
14 Q&A Saturn's moon Janus, Halley's Comet, and planetary alignments.
19 News & Reviews Chaos on Jupiter and Saturn; fundamental geology.
20 Washington Watch NASA and the Reagan Administration.
20 Society Notes Member perks at the annual AIAA meeting