The Planetary Report • September/October 1991

Seeking the Beacon

On the Cover: Clouds of interstellar dust obscure the view of our galaxy's central region which, viewed from Earth, lies in the direction of the constellation of Sagittarius. With our solar system situated on the outskirts of the Milky Way, most of its stars appear within or beyond the galactic center. If any galactic beacon engineers are beaming a message our way, chances are it will come from that direction. Part of the fun of the Search for Extraterrestrial Intelligence is trying to guess how another technological civilization might try to contact ours.


4 A Morning with Philip Morrison: Exploring the Extraterrestrial Mind: Paul Horowitz has a stimulating discussion with a pioneer of the SETI project.

8 A Clean, Well-Lighted Place: Mercury: Clark Chapman looks at the closest planet to our sun.

12 Tracking Asteroids: Why We Do It: Jeremy Tatum explains why we bother looking for all these tiny lumps of rock in space.

16 The 1991 Solar Eclipse From a Different Perspective: Charlene Anderson shows us what a solar eclipse looks like from orbit.


3 Members' Dialogue Venus, the space station, and long-duration human spaceflight.

19 International Space Year Celebrates Tomorrow's Explorers Mission to Planet Earth.

20 Q&A Why is Venus' orbit retrograde?

22 World Watch Mars '94 & '96; NASA's Discovery Program.

23 Society Notes Awards, mysteries, and events.

The Planetary Report • September/October 1991

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