Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Dirty space and supernovae

03.03.2008
Interstellar space may be strewn with tiny whiskers of carbon, dimming the light of far-away objects. This discovery by scientists at the Carnegie Institution may have implications for the “dark energy” hypothesis, proposed a decade ago in part to explain the unexpected dimness of certain stellar explosions called Type1a supernovae.

Type1a supernovae are among the brightest objects in the universe. Astronomers use them as “standard candles” to gauge cosmological distances: brighter-appearing supernovae are closer, dimmer ones are farther away. In the late 1990s some astronomers noticed that some seemed too dim—too far away—to be explained by conventional theories of the universe’s expansion. This led to the hypothesis that the expansion was accelerating, pushed along by an unknown form of energy — dark energy.

In the current study, published in the February 29 issue of Science, Andrew Steele and Marc Fries of the Carnegie Institution’s Geophysical Laboratory report the discovery of an unusual new form of carbon in minerals within meteorites dating from the formation of the solar system. These “graphite whiskers” were likely produced from carbon-rich gas at high temperatures and were found within features called calcium-aluminum inclusions, which at around 4.5 billion years old are the oldest known solids in our solar system.

“During this time when the sun was young, the solar wind was very strong,” says Fries. “So graphite whiskers formed near the sun could have been blown into interstellar space. The same thing may have happened around other young stars as well.”

Graphite whiskers might also be produced and dispersed into space by supernovae explosions.

A thin interstellar haze of graphite whiskers spewed from stars and supernovae would affect how different wavelengths of light pass through space. It has been postulated that wavelengths in the near infrared would be particularly affected. It is the dimming of light from Type 1a supernovae at these wavelengths that first led researchers to think that the universe’s expansion was accelerating and that therefore a hitherto unknown force “dark energy”must exist. However, since the 1970s it has been postulated that graphite or other whisker-like materials could explain the observations. The presence of graphite whiskers in space has never been confirmed until this study.

With the discovery of graphite whiskers in the meteorite, researchers can test their properties against the cosmological models and astronomical observations.

“If graphite whiskers in space are absorbing supernovae’s light,” says Steele, “then this could affect measurements of the rate of the universe’s expansion. While we cannot comment further on the effects of whiskers on the dark energy hypothesis it is important to study the characteristics of this form of carbon carefully so we can understand its impact on dark energy models. We’ll then feed this data forward to the upcoming NASA and ESA (European Space Agency) missions that will look for the effects of dark energy.”

Andrew Steele | EurekAlert!
Further information:
http://www.ciw.edu/

More articles from Physics and Astronomy:

nachricht From rocks in Colorado, evidence of a 'chaotic solar system'
23.02.2017 | University of Wisconsin-Madison

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

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: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>