On the Cover: On December 16, 1992, eight days after its last encounter with its home world, <i>Galileo</i> looked back and captured an image of Earth and its Moon from 6.2 million kilometers (3.9 million miles) away. The blue-and-white planet shines three times as brightly as its natural satellite. Still, to make the features stand out, both contrast and color have been enhanced in this image. Antarctica is just visible at the southern horizon of Earth.
4 A Last, Long Look Homeward: Galileo Sets Off for Jupiter: Charlene Anderson showcases how Galileo has added to our knowledge of Earth, the Moon, Venus, and an asteroid on its way to the outer solar system.
12 Planetary Prospectors Meet in Pasadena: James Burke reports from the First International Conference on Planetary Systems.
20 News From the Mars Balloon Project: Jacques Blamont gives an update on this European project.
22 Not Yet to Mars, Together—But Still Working on It: Louis Friedman examines the breakdown of U.S.–Russian attempts for joint exploration of Mars.
3 Members' Dialogue Comments on The Planetary Report.
26 News & Reviews The Space Science Series; Peekskill Fireball.
27 Society Notes Thanks for the asteroids!
28 Q&A Are plate tectonics necessary for life?