By ANDREW BRIDGES
THE ASSOCIATED PRESS

PASADENA, Calif. -- NASA's aging Galileo spacecraft deliberately plunged into Jupiter's turbulent atmosphere yesterday, bringing a fiery conclusion to a 14-year, $1.5 billion exploration of the solar system's largest planet and its moons.

The unmanned spacecraft, traveling at nearly 108,000 mph, was torn apart and vaporized by the heat and friction of its fall through the clouds after it dived into the atmosphere at 2:57 p.m. EDT (11:57 a.m. PDT) as planned.

At NASA's Jet Propulsion Laboratory, hundreds of scientists, engineers and their families counted down the last seconds before the spacecraft ended its 2.8 billion-mile journey from Earth.

"We haven't lost a spacecraft; we've gained a new steppingstone in exploration," said Torrence Johnson, the mission's project scientist.

Rosaly Lopes, another scientist on the mission, called Galileo's descent "a spectacular end to a spectacular mission."

"Personally, I am a little sad. I had the time of my life on Galileo, and I'm a little sad to say goodbye to an old friend," Lopes added.

Despite the glitches that plagued Galileo since its 1989 launch aboard the space shuttle Atlantis, it was one of the NASA's most fruitful missions.

During its thrice-extended mission, Galileo discovered the first moon of an asteroid, witnessed the impact of a comet into Jupiter and provided firm evidence of salty oceans on three of the planet's moons. Scientists consider one of the three, Europa, the most likely place in the solar system to harbor extraterrestrial life.

Among the most stunning of the 14,000 images returned by Galileo were those of the moon Io. Galileo caught some of the moon's more than 150 volcanoes actively spewing lava and plumes of dust and gas.

The last of Galileo's science measurements arrived on Earth after the spacecraft was destroyed yesterday, taking 43 minutes to cross a half-billion miles at the speed of light.

"I just can't believe the spacecraft collected data all the way in," said Claudia Alexander, Galileo's seventh and last project manager.

In Seattle, Shoreline resident Ron Hobbs, an adjunct college professor and volunteer with the NASA laboratory's Solar System Ambassadors program, spent the weekend sharing Galileo's history and achievements with visitors to the Museum of Flight. He also spoke to the morning crowd at Robb's 125th Street Grill, which held "Goodbye Galileo Breakfasts" Saturday and yesterday.

Galileo's discoveries made the program a success, he said.

"The Galileo spacecraft was probably the most troubled mission that NASA has ever run," Hobbs said. "It was delayed a number of times, and then it had to be sent on a circuitous route. It didn't get to Jupiter until 10 years after it was supposed to. The incredible engineers worked around these problems and kept extending the mission."

NASA initially considered leaving Galileo in orbit after it depleted its onboard store of fuel. Instead, it chose to crash the 3,000-pound Galileo to eliminate the possibility it could smack into Europa and contaminate it with any Earth microbes aboard.