Lofty Dreams For Space Agency
The Soviet Union launched the first satellite, the United States won the race to the moon, but Europe's space agency hopes to be the first to land on a comet.
The European Space Agency on Thursday showed off a model of the Rosetta spacecraft, designed to rendezvous with the comet Wirtanen in 2012.
Europe has taken the lead in exploring comets, made of the leftover debris from the formation of the solar system 4.6 billion years ago, said Roger Bonnet, director of science for the 14-nation agency.
"We have seized the opportunity," Bonnet said. "The United States always misses the opportunity."
Bonnet cited the agency's success in sending the Giotto probe within 375 miles of Halley's comet in 1986. Two Soviet spacecraft and a Japanese spacecraft also met the comet, but the U.S. National Aeronautics and Space Administration, hampered by budget cuts in the 1970s, missed out.
NASA had planned to put a second lander on the Rosetta mission, but was squeezed out by the need to limit the weight of the spacecraft, Bonnet said.
NASA had also hoped to launch a spacecraft in 2003 to explore the comet Tempel 1, but announced this week that the project was canceled because of cost overruns on other, more developed projects.
The United States launched its first comet mission in February - the Stardust spacecraft, which is to pass within 90 miles of the comet Wild-2 in January 2004. The mission hopes to be the first to capture dust from a comet and return it to Earth in 2006.
Unlike Giotto, which zoomed past Halley's comet, Rosetta is designed to orbit just 3,300 feet above the surface of Wirtanen after it makes its rendezvous on May 28, 2012.
At that point, the comet will be a frozen, inert hunk 420 million miles from the sun. Rosetta should then pace the comet at 81,000 mph as it approaches the sun and develops the characteristic comet tail.
Instruments aboard the craft will sample the gases and dust particles in the tail.
About a month after rendezvous, Rosetta should drop a 220-pound lander, firing a harpoon into the comet to make sure the spacecraft doesn't bounce away on impact.
Scientists are interested in comets because they are the oldest objects accessible to humans, said Gerhard Schwehm, the Rosetta project scientist.
"We do comet science to get the measurements done to understand our origins," he said.
Rosetta, named for the stone that was the key to deciphering Egyptian hieroglyphs, is designed to unlock some of the mysteries of comets: How dense are they? Are they mostly ice or dust? Why is the nucleus so dark?
Alan Fitzsimmons, a comet scientist at Queen's University in Belfast, Northern Ireland, described comets as "the leftover building bricks" from the birth of the solar system.
"Now, we have the Rosetta spacecraft to decipher our origins, to go back and touch the material which formed the Earth and all te planets," he said.