Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Supernova Shrapnel Found in Meteorite

10.09.2010
Scientists have identified the microscopic shrapnel of a nearby star that exploded just before or during the birth of the solar system 4.5 billion years ago.

Faint traces of the supernova, found in a meteorite, account for the mysterious variations in the chemical fingerprint of chromium found from one planet and meteorite to another. University of Chicago cosmochemist Nicolas Dauphas and eight co-authors report their finding in the late Sept. 10, 2010 issue of the Astrophysical Journal.

Scientists formerly believed that chromium 54 and other elements and their isotopic variations became evenly spread throughout the cloud of gas and dust that collapsed to form the solar system. “It was a very well-mixed soup,” said Bradley Meyer, a professor of astronomy and astrophysics at Clemson University who was not a co-author of the study. “But it looks like some of the ingredients got in there and didn’t get completely homogenized, and that’s a pretty interesting result.”

Scientists have known for four decades that a supernova probably occurred approximately 4.5 billion years ago, possibly triggering the birth of the sun. Their evidence: traces of aluminum 26 and iron 60, two short-lived isotopes found in meteorites but not on Earth.

These isotopes could have come from a type II supernova, caused by the core-collapse of a massive star. “It seems likely that at least one massive star contributed material to the solar system or what was going to become the solar system shortly before its birth,” Meyer said.

Researchers have already extracted many type II supernova grains from meteorites, but never from a type IA supernova. The latter type involves the explosion of a small but extremely dense white-dwarf star in a binary system, one in which two stars orbit each other. It should now be possible to determine which type of supernova contributed the chromium 54 to the Orgueil meteorite.

“The test will be to measure calcium 48,” Dauphas said. “You can make it in very large quantities in type Ia, but it’s very difficult to produce in type II.” So if the grains are highly enriched in calcium 48, they no doubt came from a type Ia supernova.

Cosmochemists have sought the carrier of chromium 54 for the last 20 years but only recently have instrumentation advances made it possible to find it. Dauphas’s own quest began in 2002, when he began the painstaking meteorite sample-preparation process for the analysis he was finally able to complete only last year.

Dauphas and his associates spent three weeks searching for chromium 54-enriched nanoparticles with an ion probe at the California Institute of Technology. “Time is very precious on those instruments and getting three weeks of instrument time is not that easy,” he said.

The researchers found a hint of an excess of the chromium-54 isotope in their first session, but as luck would have it, they had to search 1,500 microscopic grains of the Orgueil and Murchison meteorites before finding just one with definitely high levels.

The grain measured less than 100 nanometers in diameter—1,000 times smaller than the diameter of a human hair. “This is smaller than all the other kinds of presolar grains that have been documented before, except for nanodiamonds that have been found here at the University of Chicago,” Dauphas said.

The findings suggest that a supernova sprayed a mass of finely grained particles into the cloud of gas and dust that gave birth to the solar system 4.5 billion years ago. Dynamical processes in the early solar system then sorted these grains by size. These size-sorting processes led the grains to become disproportionally incorporated into the meteorites and planets newly forming around the sun.

“It’s remarkable that you can look at an isotope like chromium 54 and potentially find out a whole lot about what happened in the very first period of the solar system’s formation,” Meyer said.

Citation: “Neutron-rich chromium isotope anomalies in supernova nanoparticles,” Sept. 10, 2010, Astrophysical Journal, by Nicolas Dauphas, Laurent Remusat, James Chen, Mathieu Roskosz, Dimitri Papanastassiou, Julien Stodolna, Yunbin Guan, Chi Ma, and John Eiler.

Funding: National Aeronautics and Space Administration and National Science Foundation.

Steve Koppes | Newswise Science News
Further information:
http://www.uchicago.edu

Further reports about: Astrophysical Shrapnel Supernova gas and dust massive star meteorite solar system

More articles from Physics and Astronomy:

nachricht Astronomers find unexpected, dust-obscured star formation in distant galaxy
24.03.2017 | University of Massachusetts at Amherst

nachricht Gravitational wave kicks monster black hole out of galactic core
24.03.2017 | NASA/Goddard Space Flight Center

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: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>