UK scientists sift superfine stardust (Forwarded)

Royal Astronomical Society
London, U.K.

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Robert Massey
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AND
Anita Heward
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CONTACT:

Dr John Bridges
Space Research Centre
Dept. of Physics & Astronomy
University of Leicester
University Road
Leicester
LE1 7RH
UK
Tel: +44 (0) 116 252 2007
Fax: +44 (0) 116 252 2464

From 16-18th April, Dr Bridges can be contacted via the NAM press office
(see top of release for details).

PRESS INFORMATION NOTE: RAS PN 07/23 (NAM19)

EMBARGOED FOR 00:01 BST, WEDNESDAY, 18 APRIL 2007

UK SCIENTISTS SIFT SUPERFINE STARDUST

UK scientists are preparing to analyse miniscule impact craters collected
by NASA's Stardust mission as it flew through interstellar dust streams.
These craters contain the residues of the dust particles that are the
seeds of our own Solar System.

A UK consortium of researchers from the University of Leicester, Natural
History Museum, Kent University, Glasgow University and Open University
have been studying the cometary samples which were delivered a few weeks
after the samples were returned to Earth. The interstellar dust particles
are about ten nanometres across (one hundred thousandth of a millimetre)
and they are even smaller than many of the particles that Stardust
collected when it flew through the coma of Comet Wild 2.

In a presentation at the Royal Astronomical Society's National Astronomy
Meeting in Preston on 18th April, Dr John Bridges from the University of
Leicester will describe how techniques developed to analyse material from
the comet's tail will be used to study the interstellar particles. A
focussed beam of electrically charged particles will be used to extract
the residue of the dust from the craters. Once the material is no longer
shielded by the crater walls, it can be examined using a transmission
electron microscope.

"The interstellar dust particles collected by Stardust are so tiny that
they pose huge analytical challenges," said Dr Bridges. "Having spent the
time perfecting our techniques and analysing Comet Wild 2, we are very
excited by the prospect of these samples. Our analysis of samples from the
comet's tail revealed that its composition was more complex than we'd
thought and indicated an unexpected mixing of refractory and volatile
material in the early Solar System. The interstellar particles will take
us one step farther back and allow us to look at the composition of the
dust cloud from which the Solar System formed."

The Stardust mission spent 4 months collecting interstellar dust during
its 2.88 million mile journey to Comet Wild-2 and back to Earth. The
return capsule, containing the dust and samples from the comet's tail,
landed in the desert in Utah in January 2006. Since then, samples have
been distributed to selected researchers around the world.

FURTHER INFORMATION

The Stardust Mission

Stardust, a project under NASA's Discovery Program of low-cost, highly
focused science missions, was built by Lockheed Martin Space Systems,
Denver, Colorado, and is managed by the Jet Propulsion Laboratory,
Pasadena, Calif., for NASA's Office of Space Science, Washington, D.C.
JPL is a division of the California Institute of Technology in Pasadena.
The mission's Principal Investigator is Dr. Donald Brownlee of the
University of Washington in Seattle, WA. UK involvement is funded by the
Science and Technology Facilities Council.

More information on the Stardust mission is available at
http://stardust.jpl.nasa.gov/home/index.html

NOTES FOR EDITORS

Royal Astronomical Society's National Astronomy Meeting

The RAS National Astronomy Meeting is the UK's premier meeting for the
astronomy, solar system and space science communities. The RAS-NAM 2007 is
hosted by the University of Central Lancashire and is joined by the UK
Solar Physics and Spring MIST meetings. It is sponsored by the Royal
Astronomical Society, the UK Science and Technology Facilities Council and
the University of Central Lancashire.

IMAGES

An image of a residue-bearing impact crater from a Stardust foil can be
found at
http://www.ras.org.uk//index.php?opt...k=view&id=1179