[meteorite-list] Carnegie Scientists Fine-Tuning Methods for Stardust Analysis

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri Mar 24 10:39:15 2006
Message-ID: <200603231759.k2NHxbn15002_at_zagami.jpl.nasa.gov>

Public release date: 22-Mar-2006

Contact: Larry R. Nittler
lrn_at_dtm.ciw.edu
202-478-8460
Carnegie Institution

Carnegie scientists fine-tuning methods for Stardust analysis

On Sunday, January 15, NASA's Stardust mission landed safely with the
first solid comet fragments ever brought back to Earth. Members of the
mission's Preliminary Examination Team, including several from the
Carnegie Institution's Geophysical Laboratory and Department of
Terrestrial Magnetism, are among the first to analyze these precious
samples. The researchers are refining methods to zero in on organic
molecules--the ingredients of life--contained in the grains captured
from the coma of comet Wild-2.

The team is already generating preliminary data. For the latest news on
Stardust, as well as other studies on interstellar dust particles and
meteorites, see a series of talks and posters at the NASA Astrobiology
Science Conference (AbSciCon) 2006 at the Ronald Reagan Building in
Washington, D.C. March 26-30. See http://abscicon2006.arc.nasa.gov/ for
details.

Scientists believe comets like Wild-2 are the oldest solid bodies in the
solar system. Yet until now, no one has seen a piece of a comet up
close. Researchers expect to retrieve less than one thousandth of an
ounce of material from Stardust's collection grid, but this tiny puff of
dust might yield scientific gold: by comparing the structure and
chemistry of Stardust grains to interstellar dust and rare meteorites
rich in organic material, researchers hope to fill in some significant
holes in what we know about the evolution and history of our solar system.

"It is likely that some of the carbon in our bodies was originally bound
up in comets and delivered to the early Earth through impacts,"
explained Marc Fries of Carnegie's Geophysical Laboratory, a member of
the Preliminary Examination Team. "So when we say that 'we are stardust'
we are literally talking about the type of material that Stardust has
returned to our laboratories for analysis."

Carnegie's researchers are studying their first Stardust sample with a
brand new, $2.8 million NanoSIMS ion probe. This instrument can reveal
the chemical makeup of a sample by vaporizing tiny target areas with a
stream of ions, allowing an accurate count of the atoms emitted; the
NanoSIMS is an ideal tool for analyzing minuscule Stardust grains
because it has greater sensitivity than previous ion probes.

The team also plans to study the physical and chemical details of
Stardust grains using two different spectroscopic techniques. First, by
analyzing laser light reflected from a sample, Raman spectroscopy can
reveal both the structure of minerals and the forms of carbon present.
Second, a unique soft X-ray microscope at Lawrence Berkeley National
Laboratory's Advanced Light Source facility in California enables a
technique called XANES spectroscopy, which can help characterize the
carbon, nitrogen, and oxygen species in organic matter. Since the
carbon-containing materials from Wild-2 are likely to be little changed
since the birth of the solar system, these analyses are especially
important.

Carnegie researchers from the Geophysical Laboratory and the Department
of Terrestrial Magnetism will discuss the analysis of interstellar
matter, including early isotopic and spectroscopic results from
Stardust, in several talks and posters at AbSciCon 2006.

###

Talk and poster schedule subject to change. See
http://abscicon2006.arc.nasa.gov/agenda.php for the latest information.

1Henner Busemann et al., "Comparative Isotope and Micro-Raman Analyses
of Meteoritic Organic Matter and Interplanetary Dust Particles"
Wednesday, March 29, 2006, 10:45am
Reagan Center, Horizon A&B conference room, Session 22: Extraterrestrial
Prebiotic Chemistry II

2Hikaru Yabuta et al., "Extracting Building Blocks of Insoluble Organic
Matter in Meteorites by CuO-NaOH Degradation Technique:
Search of Biomolecule Precursors"
Wednesday, March 29, 2006, 11:05am
Reagan Center, Horizon A&B conference room, Session 22: Extraterrestrial
Prebiotic Chemistry II

3George Cody et al., "Extraterrestrial Organics and the Chemical History
They Reveal"
Poster displayed throughout the conference. Poster session Monday night,
March 27, 2006, 6-8pm
Reagan Center, Atrium Hall

4Larry Nittler et al., "Microscale Isotopic Heterogeneity in
Extraterrestrial Carbon"
Poster displayed throughout the conference. Poster session Monday night,
March 27, 2006, 6-8pm
Reagan Center, Atrium Hall

5Conel Alexander et al., "Spectroscopic Studies of Meteoritic Organic
Matter"
Poster displayed throughout the conference. Poster session Monday night,
March 27, 2006, 6-8pm
Reagan Center, Atrium Hall

NASA provided funds in support of this work through the Stardust
Participating Scientist Program. NASA's Sample Return Laboratory
Instrument and Data Analysis Program (SRLIDAP) funded both the Raman
instrument and a portion of the cost of the NanoSIMS ion probe. NASA
also provided partial support for work at the Advanced Light Source, a
facility funded by the US Department of Energy.

The Carnegie Institution of Washington has been a pioneering force in
basic scientific research since 1902. It is a private, nonprofit
organization with six research departments throughout the U.S. Carnegie
scientists are leaders in plant biology, developmental biology,
astronomy, materials science, global ecology, and Earth and planetary
science. See www.carnegieinstitution.org .

This work is supported by the NASA Astrobiology Institute (NAI). The
NAI, founded in 1998, is a partnership between NASA, 16 major U.S. teams
and six international consortia. NAI's goal is to promote, conduct, and
lead integrated multidisciplinary astrobiology research and to train a
new generation of astrobiology researchers. For more information about
the NAI on the Internet, visit: http://nai.nasa.gov/
 
Received on Thu 23 Mar 2006 12:59:37 PM PST