ET Asteroid Dust May Reveal Secrets of Solar System’s Birth

Article-1330116-0C17438C000005DC-447_468x357 Japan's Hayabusa space probe has become the first spacecraft to bring material from an asteroid back to Earth, the Japanese Aerospace Exploration Agency (JAXA) announced. Hayabusa's capsule was retrieved earlier this year, howver it wasn't clear whether the dust it contained came from the asteroid it landed on in 2005 until an analysis by JAXA has shown that the dust's composition is extra-terrestrial, even containing a mineral not found on the Earth's surface. Additional analysis may reveal what materials existed when the solar system formed, and provide insights into how best to mitigate asteroid impacts based on new knowledge of their composition.

"The science that we will obtain from these particles over the next few years will be invaluable," said Paul Abell of the NASA Johnson Space Center in Houston, Texas, who is a member of the Hayabusa Joint Science Team.

"After all the hard work and the many years of patiently waiting, we now can say that we have returned samples from an asteroid to the Earth for the very first time," he says.

After analysing some 1500 particles using scanning electron microscopes, JAXA says that nearly all the material was extraterrestrial and originated in Itokawa. The presence of elements and minerals in the dust – including olivine and plagioclase – are similar to what is seen in primitive meteorites and do not correspond to the make-up of any rock found on Earth's surface, JAXA reports. One mineral identified in the dust, troilite (an iron sulphide), is not present on the Earth's surface.

Over the next few years, the particles will be analysed further to see if they have retained minerals from the early solar system, unlike meteorites whose composition may have been altered by the high pressures and temperatures they encounter as they crash to Earth.

Casey Kazan via


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