Although the Voyager 1 spacecraft has finished its Saturn mission, Voyager scientists have scarcely begun their work. "It's nontrivial analysis task ahead of us," said project scientist Edward Stone with calculated understatement.
As an example of what he meant, he noted that project scientists do not yet know the diameter of the moon Titan. "It's buried in those data that were coming in one image every second," he said, adding that it will take weeks to break out the right number, if indeed it an be found at all.
And the size of Titan -- that is, size of the solid body underlying the thick atmosphere -- is only one of hundreds of facts about the Saturn system that scientists are trying to pin down.
Already, it is obvious that planetary science has leaped ahead. More knowledge has been gained about the Saturnian system during Voyager 1's flyby than was learned throughout all previous human history.
Consider Titan itself, one of the largest moons in the solar system and the only one known to have a substantial atmosphere. Although its surface could not be seen and its exact size is still in doubt, Dr. Stone says scientists "still have learned a great deal about Titan in the sense that this is a big first step."
They have data showing how temperature varies with height throughout Titan's atmosphere. They now know Titan has a thick atmosphere with a surface pressure at least 1.5 times the sea-level pressure on Earth. And they may be able to define that pressure more exactly. They have know the basic composition of that atmosphere, which consists largely of hydrogen with an intriguing mixture of organic chemicals.