Editorial: New worlds of knowledge

Saturday, Jan. 21, 2006 | 8:18 a.m.

In looking at maps of the sun and its planets, and in reading about them, it would be easy to conclude that man's knowledge of the solar system is vast. But that would be just as mistaken as the ancient belief that the Earth is the center of the universe.

In truth, we know very little about our solar system. Scientists can only theorize about its origin, and our knowledge of the distant planets, moons, comets, rings and belts is rudimentary at best. We're not even sure how many planets there are. A 10th planet was identified last year year and there may be more.

Our knowledge has been increasing, though, ever since NASA undertook unmanned solar missions in the 1960s. As 2004 was a banner year for that project when NASA landed rovers on Mars, this was a banner week. A spacecraft that had traveled 3 billion miles since its 1999 launch landed in the Utah desert Monday. Its payload was comet and star dust that date back more than 4 billion years, possibly to the time the solar system came into being. Scientists believe analysis of the dust may yield clues about how it all began.

On Thursday NASA launched another unmanned spacecraft, called New Horizons, on a 3 billion-mile expedition to mysterious Pluto. In February 2007 the spacecraft will use gravity from Jupiter to "slingshot" itself into the outer solar system, reducing the trip to nine years instead of 12 or more.

We envy future generations, who will know much more about our solar system, thanks to NASA's ongoing explorations.