Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New meteorite suggests that asteroid surfaces more complex than previously thought

21.12.2012
Scientists around the world work together on speedy space rock analysis

Meteorites that had fallen from an asteroid impact that lit up the skies over California and Nevada in April are showing scientists just how complex an asteroid surface can be.


These are some of the 77 fragments of the Sutter’s Mill meteorite fall that were collected in April 2012.

Credit: NASA/E. James

A new study published in Science this week by an international team of researchers describes the speedy recovery of the meteorites and reports that this space rock is an unusual example from a rare group known as carbonaceous chondrites, which contain some of the oldest material in the solar system.

The study of these meteorites and others like them could hold answers to unsolved mysteries about the origin of life on Earth as they contain molecules such as water and amino acids.

"We found that this meteorite is a 'breccia,' a mixture of different rocks that accumulated at the surface of a larger asteroid, and those surfaces can be more diverse than we thought before," said co-author Denton Ebel, chair of the Division of Physical Sciences at the American Museum of Natural History.

About eight months ago, several Doppler weather radars detected a hail of rocks following a fireball traveling at a record-breaking 28.6 kilometers per second (about 64,000 miles per hour) over the Sierra Nevada in northern California. An immediate search-and-recover mission, led by NASA Ames Research Center, the SETI Institute, and the University of California, Davis, resulted in the retrieval of 77 meteorites. The fragments, which were in pristine shape despite entering the atmosphere at a speed twice as fast as a typical meteorite fall, were collectively called the Sutter's Mill meteorite after the nearby historical site that started the California Gold Rush.

"From the loud sonic boom, we quickly realized that this was an asteroid several meters in size, the biggest object to hit over land since the impact of asteroid 2008 TC3 in the north of Sudan in 2008," said lead author and meteor astronomer Peter Jenniskens of NASA Ames and SETI. "That asteroid proved to be a mixed bag of different types of meteorites, and we realized it would be very interesting to find out how diverse the Sutter's Mill meteorites were."

Several fragments were sent to laboratories around the world for simultaneous analysis of the meteorite's mineralogy and structure. The Sutter's Mill meteorite was classified as a CM chondrite, C standing for carbonaceous—high in carbon content—and M standing for the group's type specimen, the Mighei meteorite that fell in Ukraine in the late 1800s.

Ebel received five Sutter's Mill meteorites to study using x-ray computed tomography (CT), an imaging technique that takes pictures of the inside of a specimen without destroying it. The Museum's scanner takes more than 1,000 x-ray images of the object as it rotates inside of the machine. The data collected from these x-rays are then converted by computers to form a 3-D image of the specimen's interior, one slice at a time, to understand the components of the meteorite.

"In the same way that medical tomography, called CAT scanning, is used to image the interior of the human body, CT scanning in a research laboratory allows us to obtain images of the interiors of solid objects, but with a much higher resolution," Ebel said. "This is a fundamentally important tool not just for looking at rocks but for curating them and figuring out whether anything interesting is inside."

CT scans at the Museum, and at the University of California, Davis in an effort led by cosmochemist Qing-Zhu Yin, revealed that no two Sutter's Mill meteorites are the same. The meteorites contained angular pieces of different composition and density. They showed diversity on millimeter scale.

"This was the first time that a CM chondrite was found to be clearly a breccia," Yin said. "The rocky fragments came together following impacts on the parent asteroid, which implies that this meteorite originated from near its surface."

Analyses performed using different techniques at other institutions were in agreement: the mineralogy and other geochemical features of these fragments are unexpectedly diverse and complex. This suggests that the surface of the asteroid that spawned the CM chondrites, their "parent body," is more complex than previously thought.

"This meteorite is special because it records many collisional processes and mixing that we, oddly, don't see very often," Ebel said. "Maybe the real question is 'why don't we see more of this?' It could be that most of the samples we've worked with in the past didn't hold up very well as they entered the atmosphere. Or that we're just seeing a small segment of what's really out there because we don't have meteorite records of what fell to the Earth thousands or millions of years ago. We still have a lot of work to do to figure out what's really going on in the asteroid belt."

Kendra Snyder | EurekAlert!
Further information:
http://www.amnh.org

More articles from Earth Sciences:

nachricht A Volcanic Binge And Its Frosty Hangover
21.02.2019 | Universität Heidelberg

nachricht Researchers get to the bottom of fairy circles
21.02.2019 | Georg-August-Universität Göttingen

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: (Re)solving the jet/cocoon riddle of a gravitational wave event

An international research team including astronomers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has combined radio telescopes from five continents to prove the existence of a narrow stream of material, a so-called jet, emerging from the only gravitational wave event involving two neutron stars observed so far. With its high sensitivity and excellent performance, the 100-m radio telescope in Effelsberg played an important role in the observations.

In August 2017, two neutron stars were observed colliding, producing gravitational waves that were detected by the American LIGO and European Virgo detectors....

Im Focus: Light from a roll – hybrid OLED creates innovative and functional luminous surfaces

Up to now, OLEDs have been used exclusively as a novel lighting technology for use in luminaires and lamps. However, flexible organic technology can offer much more: as an active lighting surface, it can be combined with a wide variety of materials, not just to modify but to revolutionize the functionality and design of countless existing products. To exemplify this, the Fraunhofer FEP together with the company EMDE development of light GmbH will be presenting hybrid flexible OLEDs integrated into textile designs within the EU-funded project PI-SCALE for the first time at LOPEC (March 19-21, 2019 in Munich, Germany) as examples of some of the many possible applications.

The Fraunhofer FEP, a provider of research and development services in the field of organic electronics, has long been involved in the development of...

Im Focus: Regensburg physicists watch electron transfer in a single molecule

For the first time, an international team of scientists based in Regensburg, Germany, has recorded the orbitals of single molecules in different charge states in a novel type of microscopy. The research findings are published under the title “Mapping orbital changes upon electron transfer with tunneling microscopy on insulators” in the prestigious journal “Nature”.

The building blocks of matter surrounding us are atoms and molecules. The properties of that matter, however, are often not set by these building blocks...

Im Focus: University of Konstanz gains new insights into the recent development of the human immune system

Scientists at the University of Konstanz identify fierce competition between the human immune system and bacterial pathogens

Cell biologists from the University of Konstanz shed light on a recent evolutionary process in the human immune system and publish their findings in the...

Im Focus: Transformation through Light

Laser physicists have taken snapshots of carbon molecules C₆₀ showing how they transform in intense infrared light

When carbon molecules C₆₀ are exposed to an intense infrared light, they change their ball-like structure to a more elongated version. This has now been...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Global Legal Hackathon at HAW Hamburg

11.02.2019 | Event News

The world of quantum chemistry meets in Heidelberg

30.01.2019 | Event News

Our digital society in 2040

16.01.2019 | Event News

 
Latest News

JILA researchers make coldest quantum gas of molecules

22.02.2019 | Physics and Astronomy

Understanding high efficiency of deep ultraviolet LEDs

22.02.2019 | Materials Sciences

Russian scientists show changes in the erythrocyte nanostructure under stress

22.02.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>