Science: Off to Saturn

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And maybe Titan too

It took nearly 6½ years and a journey of 2 billion miles, but NASA's Pioneer 11 spacecraft is also on the verge of making history. On Saturday, Sept. 1, the 260-kg (570-lb.) robot will become the first envoy from earth to reconnoiter Saturn, passing within 21,300 km (13,300 miles) of the solar system's second largest planet. If the flyby goes as planned, Pioneer 11 will not only send back 50 colored closeups of the great ringed gaseous sphere but provide valuable data on its interior structure, temperature, density and magnetic field (if any).

Controllers at NASA's Ames Research Center, near San Francisco, say that the probe could be destroyed as it swoops close to the outermost of Saturn's thin visible rings. But safe passage should provide a scientific bonus. After passing Saturn, Pioneer 11 will turn its electronic eyes on Titan, largest of Saturn's ten known moons, which seems to have a solid surface and methane atmosphere. The satellite could shelter organic molecules and—it is an extreme long shot—even primitive life forms. Since scientists have found no life on Venus, Mars or Jupiter, sighs Project Scientist John Wolfe, "Titan is sort of the biologist's last hope."