On the Cover: As Giotto closed in on Halley's Comet, it took this image of the peanut-shaped nucleus from 18,000 kilometers away. Scientists estimate the nucleus to be roughly 15 x 6 kilometers in size, somewhat larger than expected. The Sun illuminates the comet from the lower right side, warming the icy nucleus and causing bright dust jets to burst outward. The dark region on the upper left section of the nucleus has not yet been identified. Max Planck Institut fur Aeronomie
4 Sifting Through Starlight: Evidence for Circumstellar Dust Disks: Lewis Hobbs presents the circumstantial evidence for planetary systems orbiting other stars.
12 Visiting a Comet: ICE Flies Through Giacobini-Zinner: Edward J. Smithgives a brief overview of the results from this mission.
10 News & Reviews Oil crisis, wandering poles on Mars, and the politics of space.
11 World Watch Flying by Halley's Comet with the Vega missions.
14 Society Notes On to Mars; asteroid search funded.
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