US spacecraft Galileo ended its 14-year odyssey Sunday in a suicide plunge into the scorching atmosphere of Jupiter, the largest planet in the solar system.
Screaming down at a speed of 48.2 kilometers per second, equivalent of traveling from Los Angeles to New York City in 82 seconds, the 2.5-ton spacecraft dived into Jupiter's atmosphere at 2:57 p.m. EDT (1857 GMT) and was expected to burn up rapidly through friction.
The spacecraft will end up as another speck of cosmic debris in Jupiter and would not be nearly as observable as the fragments of Comet Shoemaker-Levy 9, which crashed into the planet in 1994, scientists said.
Hundreds of people involved in the Galileo program gathered at US space agency NASA's Jet Propulsion Laboratory to observe the grand finale.
"It has been a fabulous mission for planetary science, and it is hard to see it come to an end," Dr. Claudia Alexander, Galileo project manager at the laboratory, said earlier in a statement.
Launched aboard space shuttle Atlantis in 1989, Galileo arrived at Jupiter in December 1995 and had circulated the giant planet 34 times in the following eight years.
At a total cost of US$1.4 billion, the mission was the first to measure Jupiter's atmosphere directly with a descent probe and the first to conduct long-term observations of the Jovian system from orbit.
During its 35 encounters of Jupiter's major moons, it detected evidence of subsurface liquid layers of salt water on moons Europa, Ganymede and Callisto and examined extensive volcanic activity on the moon Io.
It was also the first spacecraft to fly by an asteroid and the first to discover a moon of an asteroid.
Galileo's death sentence was a result of one its greatest findings that Jupiter's moon Europa has an underground ocean that might harbor life.
Controllers at NASA purposely set Galileo on a collision course with Jupiter to eliminate any chance of an unwanted impact between the spacecraft and Europa.
Such an impact, scientists fear, could contaminate the Jovian moon with Earth microbes that might have survived as stowaways in the spacecraft, confounding future searchers for indigenous life on Europa. (Xinhua News Agency September 22, 2003)
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