CNN - Galileo skims past Jupiter's largest moon

Galileo skims past Jupiter's largest moon

June 27, 1996
Web posted at: 12:50 p.m. EDT (1650 GMT)

PASADENA, California (CNN) -- The spacecraft Galileo has flown close enough to the largest moon in the solar system to take a good look at its Earth-like features, but pictures of the close encounter won't be delivered back home for a couple weeks.

Galileo marked the beginning of its grand tour of Jupiter's environs with the close flyby of Ganymede. It came within 524 miles (843 km) of the planet-sized hunk of ice and rock, at 2:29 a.m. EDT (0629 GMT) Thursday.

Ganymede is bigger than the planet Mercury and three-quarters the size of Mars. Pictures taken as Galileo approached are expected to be received on Earth in a steady flow over the next few days, JPL spokesman Frank O'Donnell said Thursday.

But the first pictures from the flyby won't be available until July 10.

Employees of the Jet Propulsion Laboratory in Pasadena and their friends and families -- about 250 people in all -- gathered early Thursday morning to celebrate the flyby.

Cheers went up as confirmation of the close approach was received.

"It was an exciting moment for everyone. Some of these people have dedicated most of their careers to this project," O'Donnell said. Galileo was conceived in the early 1970s and given the go ahead by Congress in 1977.

With a diameter of 3,269 miles (5,261 km), Ganymede is the largest moon in the solar system and has many Earth-like geological features, such as craters, large valleys and mountains.

Galileo's instruments started taking continuous measurements of the moon on Sunday as the spacecraft approached.

The spacecraft has already had a second-hand close approach to Jupiter itself. A probe from the 2.5-ton spacecraft successfully entered the Jovian atmosphere on December 7 and transmitted data for about 58 minutes before burning up as planned in the planet's gaseous environment.

Galileo's epic trip through space has been likened to a journey to the beginning of time because Jupiter's atmosphere is believed to have changed less than that of any other planet in the solar system. The spacecraft is gleaning information that could help scientists learn how the solar system began.

Galileo, as it continues to orbit Jupiter, is to have close encounters with Callisto and Europa, two other of the four largest of the planet's 16 moons. After two years in the Jovian system, the spacecraft's orbit will fail and it will plunge into the planet's atmosphere to burn up.

Named after the Italian astronomer who discovered Jupiter's four largest moons in 1610, Galileo was launched from the space shuttle Atlantis on October 18, 1989. It's roundabout path took it close to Venus and brought it back near Earth twice in slingshot maneuvers that gave it the impetus to get to Jupiter, 389 million miles (626 million km) away. The project so far has cost $1.5 billion.

The Associated Press and Reuters contributed to this report.

Feedback

Send us your comments.
Selected responses are posted daily.

Galileo skims past Jupiter's largest moon

Feedback

| CONTENTS | SEARCH | CNN HOME PAGE | MAIN TECHNOLOGY PAGE |