Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Counting atoms that aren’t there, in stars that no longer exist

30.01.2004


Argonne researchers use specialized instrument



Researchers at the U.S. Department of Energy’s Argonne National Laboratory have reached for the stars – and seen what’s inside.

Argonne scientists, in collaboration with colleagues at the University of Chicago, Washington University and the Universita di Torino in Italy, examined stardust from a meteorite and found remnants of now-extinct technetium atoms made in stars long ago.


The stardust grains are tiny bits of stars that lived and died before the solar system formed. Each grain is many times smaller than the width of a human hair, and carries a chemical record of nuclear reactions in its parent star.

Famed scientist P.W. Merrill fifty years ago observed the signature of live technetium - an element that has no stable isotopes - in the starlight from certain types of stars, thereby proving the then-controversial theory that stars make atoms via a process called nucleosynthesis. The researchers’ discovery that their stardust grains once harbored live technetium brings the science of nucleosynthesis full circle.

"Finding traces of technetium decay products in stardust provides a very precise confirmation of the theories of how atoms are made inside stars," said Michael Savina, Argonne scientist and the lead author on the research, which is published today in Science. "The fact that we can both predict and measure very tiny effects in the chemistry of these grains gives us a lot of confidence in our models of how stars work."

Authors on the report, in addition to Savina, are Michael Pellin and C. Emil Tripa of Argonne, Andrew M. Davis and Roy S. Lewis of the University of Chicago, Sachiko Amari of Washington University in St. Louis, and Roberto Gallino of Universita di Torino in Italy. Funding was provided by the U.S. Department of Energy Office of Science, the University of Chicago, NASA, and the Italian FIRB Progetto Origine Astrofisica degli Elementi Pesanti Oltre il Ferro.

The work was made possible by a specialized instrument at Argonne called CHARISMA, the only instrument of its type in the world. "CHARISMA is designed to analyze very tiny samples – the kind where you can’t afford to waste atoms, because there are so few of them to work with," Savina said.

CHARISMA is presently being upgraded, with funding from the Department of Energy Office of Science and from NASA, in anticipation of samples from the Genesis mission to collect samples of the solar wind – single atoms and electrically charged particles from the sun – which scientists believe hasn’t changed since the sun was born.

The research group at Argonne will be among the scientists to analyze the samples in an effort to better understand how the planets formed. Current measurements of the sun’s composition are not precise enough to answer key questions about events in the early solar system. The researchers are also preparing to analyze samples from the Stardust mission, which recently captured dust grains from a comet’s tail and will bring them back to Earth in 2006.


The nation’s first national laboratory, Argonne National Laboratory conducts basic and applied scientific research across a wide spectrum of disciplines, ranging from high-energy physics to climatology and biotechnology. Argonne has worked with more than 600 companies and numerous federal agencies and other organizations to help advance America’s scientific leadership and prepare the nation for the future. The University of Chicago operates Argonne as part of the U.S. Department of Energy’s national laboratory system.

Catherine Foster | EurekAlert!
Further information:
http://www.anl.gov/

More articles from Physics and Astronomy:

nachricht NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center

nachricht Pluto's hydrocarbon haze keeps dwarf planet colder than expected
16.11.2017 | University of California - Santa Cruz

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>