Cassini Spacecraft Reaches Its Target

July 1, 2004 -- Until now, Saturn had 31 known moons. Today, it has one more.

It's not a traditional moon, but a spacecraft that's now circling the planet. After a seven-year, 2-billion-mile trip from Earth, the Cassini spacecraft fired its engine right on schedule overnight, gently slowing itself into orbit around the giant ringed planet. And today, NASA scientists received images from the spacecraft that represent the best view the spacecraft will ever have of the planet's mysterious rings.

"Absolutely mind-blowing," imaging team leader Carolyn Porco said as a dark, streaked picture of the rings flashed on NASA's large screen. "Look at that sharp edge. That brings tears to my eyes."

Porco explained that scientists like herself can glean the most information from such sharp images in pictures sent from space.

The mood was no less jubilant several hours earlier when engineers at the Jet Propulsion Laboratory in Pasadena, Calif., received the signal that the ship's engine was working.

"Lots of hugs and high-fives in mission control," a NASA engineer said as the team learned all was going to plan.

From that point on, the mood was upbeat but mostly quiet. Cassini — so far from Earth that its radio signals took an hour and 24 minutes to reach home — was on autopilot. All controllers could do was listen, and hope they had not missed anything when they planned the mission.

So far, it appears they succeeded.

"This whole mission has been an incredibly smooth one to fly," said Julie Webster, the flight director for the orbital insertion maneuver.

The engine burn, which lasted more than an hour and a half, apparently ran within a second of what engineers expected.

Largest Probe in U.S. History

The Cassini probe would weigh more than 12,000 pounds on Earth, and it cost $3.3 billion to build and fly. It is the largest unmanned probe the United States has ever launched, and it was decades in the making.