Nasa projectile hits comet
2005-07-04 08:18
Pasadena, California - A space probe hit its comet target early on Monday in a Nasa-directed, Hollywood-style mission that scientists hope will reveal clues to how the solar system formed.
It marked the first time a spacecraft had touched the surface of a comet, and ignited a dazzling fireworks display in space.
The successful strike 134 million kilometres away from Earth occurred just before 06:00, according to mission control at Nasa's Jet Propulsion Laboratory in Pasadena, which is managing the US$333m - about R2 281m - mission.
Scientists at mission control erupted in applause and hugged each other as news of the impact spread.
It was a milestone for the US space agency, which hopes the experiment will answer basic questions about the origins of the solar system.
The cosmic smash-up did not significantly alter the comet's orbit around the sun and Nasa said the experiment does not pose any danger to Earth.
An image by the mothership showed a bright spot in the lower section of the comet where the collision occurred that hurled a cloud of debris into space.
When the dust settles, scientists hope to peek inside the comet's frozen core - a composite of ice and rock left over from the early solar system.
"We hit it just exactly where we wanted to," co-investigator Don Yeomans said.
More than 10 000 people packed Hawaii's Waikiki Beach to see the impact on a giant movie screen.
'Like a sci-fi movie'
"It's almost like one of those science fiction movies," said Steve Lin, a Honolulu physician as his 7-year old son, Robi, zipped around his beach blanket.
Scientists had compared the suicide journey to standing in the middle of the road and being hit by a semi-truck roaring at 37 000kph. They expect the crater will be anywhere from the size of a large house to a football stadium and between two and 14 stories deep.
A day earlier, the Deep Impact spacecraft successfully released its barrel-sized "impactor" probe on a high-speed collision course with Tempel 1 - a pickle-shaped comet half the size of Manhattan.
After its release, the battery-powered probe tumbled in free flight toward the comet and flew on its own without human help during the critical two hours before the crash, firing its thrusters to get the perfect aim of the comet nucleus.
A direct hit was a challenge because Nasa's Jet Propulsion Laboratory no longer controlled the probe once it was released from the spacecraft. Even so, the odds favoured success based on previous testing.
Along the way, as the comet closed in, the copper probe took close-up pictures of the icy celestial body at a rapid clip until its destruction. The carefully orchestrated crash gave off energy equivalent to exploding nearly 5 tons of dynamite.
- AP