Scientists analyse space dust
2006-02-21 10:00
Houston - Astrophysicists have begun to analyse millions of microscopic specks of interstellar dust brought back to earth last month by the Stardust space probe, the United States space agency Nasa said on Monday.
"We're just starting to work on this ... it will take years to analyse," said Stardust mission scientific leader and University of Washington astrophysicist Don Brownlee.
Scientists are particularly excited at analysing particles gathered from the Wild Two comet that the probe flew by in January 2004, he said.
"We believe materials coming out of comets now is the same material that went into comets 4.5 billion years ago," Brownlee said at the annual meeting of the American Association for the Advancement of Science (AAAS) ending on Monday.
"Dust plays a very important role to explain both the birth of solar systems and the death of solar systems," said Iowa University astronomer Lee Ann Wilson.
Computers used to analyse space dust
A Stardust capsule carrying a teaspoonful of space dust parachuted to earth in the Utah desert on January 15 after a nearly seven-year journey across 4.63 billion kilometres.
The dust was captured in super-light "aerogel", a sturdy, sponge-like solid carried on the spacecraft. Some of the interstellar particles were collected as the craft passed through the aura of the comet Wild Two. The rest were harvested along the course of the Stardust craft's journey.
Scientists said the job of analysing particles measuring a few microns in diameter (one micron equals one millionth of a metre) begins by slicing the particles in hundreds of even smaller pieces with the help of a computer.
So far, the analysis has yielded traces of Olivine crystals, a mineral found in abundance in space, and other components, said Brownlee.
The interstellar dust will be analysed in about 150 experiments by scientists around the world, Brownlee said, adding that the laboratories were provided the samples for free.
The first, preliminary results of the Stardust mission will be given at a conference on lunar science from March 13-17 in Houston, Texas.