Spacecraft scores direct hit on comet

The probe finds its Tempel 1 target. Picture / Reuters

PASADENA - A Nasa spacecraft collided with a comet half the size of Manhattan last night, creating a brilliant cosmic smash that capped a risky voyage to uncover the building blocks of life on Earth.

"We hit it just exactly where we wanted," said Don Yeomans, of Nasa's Jet Propulsion Laboratory.

The spectacular collision, 134 million kilometres from Earth, unleashed a spray of below-surface material formed billions of years ago during the creation of the solar system.

"As of now, I think we have a completely different understanding of our solar system," said laboratory director Charles Elachi. "Its success exceeded our expectations."

The washing-machine-sized probe, which made three final targeting manoeuvres in the mission's last two hours, crashed into comet Tempel 1 right on schedule.

It snapped images of its rocky terrain until 3.7 seconds before impact.

An image of the crash taken by Deep Impact, the mission's mother ship, showed a brilliant burst of material coming from the bottom of the avocado-shaped comet.

"The impact was bigger than I expected, and bigger than most of us expected," Yeomans said. "We've got all the data we could possibly ask for and the science team is ecstatic."

Staff in the US$333 million ($490 million) mission's control room cheered and hugged one another upon confirmation of the crash.

Photographs taken by the probe in the seconds before the crash showed rocky terrain, on the comet's surface.

Nasa's space telescopes, including Hubble, the Chandra X-ray Observatory and dozens of ground observatories saw the impact.

More than 10,000 people packed Hawaii's Waikiki Beach to see the impact on a giant movie screen.

 

The size of the crater created by the copper-fortified impactor was expected to range from that of a large house to a football stadium.

The Jet Propulsion Laboratory team watched as Deep Impact, which recorded the crash from a safe distance, oriented itself and slowed in preparation for releasing the impactor on its collision course.

After placing itself in the proper orbit, the fly-by craft turned back and snapped a black-and-white image of the impactor hurtling away at 37,100km/h - the speed it would take to fly from Auckland to Sydney in about six minutes.

The mission was likened to hitting a bullet with a bullet while taking a picture with a third bullet flying by.

* A Russian astrologist who says Nasa has altered her horoscope by crashing the spacecraft into the comet is suing it for US$300 million ($444 million) damages.

"It is obvious that elements of the comet's orbit, and correspondingly the ephemeris, will change after the explosion, which interferes with my astrology work and distorts my horoscope," Izvestia quoted astrologist Marina Bai as saying in legal documents.

- REUTERS