- The Washington Times - Thursday, July 1, 2004

PASADENA, Calif. (AP) — Just hours after swooping into orbit around Saturn, the Cassini spacecraft sent “absolutely mind-blowing” images of the giant planet’s rings back to Earth early yesterday.

The first shadowy close-ups of ring segments were taken from the U.S.-European craft as it entered orbit late Wednesday. As more and more pictures came in yesterday, the images from the dark side of the rings gradually gave way to increasingly clear pictures.

“Wow, look at that scallop on the inner edge. That’s a beauty,” imaging scientist Jeff Cuzzi said as a picture from the sunlit side of the rings was displayed.

Mission scientists and engineers at NASA’s Jet Propulsion Laboratory had watched tensely late Wednesday as a signal indicated first that Cassini — launched nearly seven years ago — had passed safely through the ring plane and then performed a crucial engine firing. It squeezed through a gap in Saturn’s shimmering rings, fired its brakes and settled into a near-perfect orbit around the giant planet.

“I can tell you it feels awfully good to be in orbit around the lord of the rings,” said Charles Elachi, JPL director and Cassini radar team member.

Mission officials huddled before a control room screen as the raw images arrived from more than 900 million miles away.

Some ring segments appeared as a bland haze. Others resembled ripples in water or crisp bands of light and dark.

Putting the first spacecraft into orbit around Saturn marked another major success this year for the National Aeronautics and Space Administration, which has had two rovers operating on Mars since January and has a spacecraft heading home with samples from a comet encounter.

NASA Administrator Sean O’Keefe called the reaching of orbit around Saturn an “amazing victory” and part of a “double-header,” after a successful spacewalk by the International Space Station crew earlier Wednesday evening.

A carefully choreographed maneuver allowed Cassini to be captured by Saturn’s gravity as it arced within 12,500 miles of the giant planet’s cloud tops.

Using its big radio dish as a shield against small particles, the spacecraft ascended through a gap between two of the rings, then spun around and fired its engine for more than 11/2 hours to slow its acceleration.

The craft then rotated again to place its shielding antenna in front as it descended back through the gap.

The maneuver had to be carried out automatically because Earth and Saturn are currently more than 900 million miles apart and radio signals take more than 80 minutes to travel each way.

Navigation team chief Jeremy Jones said initial analysis showed the orbit to be so good that a “cleanup” maneuver planned for tomorrow would be small.

Cassini now will go on at least a four-year tour of Saturn and some of its 31 known moons. Cassini was scheduled to make 76 orbits and repeated flybys of the moons.

Scientists hope the mission will provide important clues about how the planets formed. Saturn, the sixth planet from the sun and the second-largest, intrigues scientists because it is like a model of the early solar system, when the sun was surrounded by a disk of gas and dust.

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