Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

University of Georgia researchers show component of mothballs is present in deep-space clouds

04.09.2009
Interstellar clouds, drifting through the unimaginable vastness of space, may be the stuff dreams are made of. But it turns out there's an unexpectedly strange component in those clouds, and it's not dreams but—mothballs?

Well, not exactly, but researchers from the University of Georgia have just shown for the first time that one component of clouds emitting unusual infrared light know as the Unidentified Infrared Bands (UIRs) is a gaseous version of naphthalene, the chief component of mothballs back on Earth. The UIRs have been seen by astronomers for more than 30 years, but no one has ever identified what specific molecules cause these patterns.

The discovery that a special kind of naphthalene with a single extra proton is out in space is important to those studying interstellar regions for many reasons. One of the most important is that the UIRs are associated with interstellar dust, and understanding the components of that dust could give clues to the origin of these mysterious voyagers. The new information may also provide insights into stellar lifecycles.

The research, led by Michael Duncan, Regents Professor of Chemistry at UGA, was just published in the Astrophysical Journal. The department of chemistry is part of UGA's Franklin College of Arts and Sciences. Co-authors on the paper were Allen Ricks, a doctoral student in Duncan's lab and Gary Douberly, formerly a postdoctoral associate in Duncan's lab and now an assistant professor in the department of chemistry at UGA.

The work was supported by the National Science Foundation.

"This came about because we found a way in our lab to make protonated naphthalene ions," said Duncan, "and that allowed us to examine its infrared spectrum. It turned out to be a near-perfect match for one of the main features in the UIRs."

That naphthalene is part of the UIRs is not totally unexpected, as it is composed of only hydrogen and carbon. Hydrogen composes by far the largest part of interstellar clouds, and carbon is another abundant element there. (This is known because scientists can measure their "light signals" or spectra and compare them to such spectra that can be generated in labs.) Still, it opens an entirely new area of study for astrophysicists and chemists who continue to understand the composition of space and the origins of the Universe.

Most people know naphthalene in its earthly crystalline form as C10H8, meaning it has 10 molecules of carbon and eight of hydrogen. The spectrum of this form of naphthalene does not match the UIRs. Duncan and his colleagues, however, had reason to believe that adding an extra proton to naphthalene (from the abundant hydrogen in space), which latches on in an unlikely space collision to give it the formula C10H9 +, might cause just the kind of change in its spectrum to match the UIR pattern.

To see if the component out there in space is protonated naphthalene, they had to first create it in the lab, under conditions near Absolute Zero and then zap it with a laser, turning it into a gas, whose infrared spectrum could then be analyzed. The bad news is that "infrared" refers to radiation whose wavelength is longer than that of visible light and so can't be seen by the naked eye. The good news is that the sophisticated machines in Duncan's lab can both "see" infrared spectrum, and identify what molecule produced it, allowing the distinctive spectrum of protonated naphthalene to be measure for the first time.

It turned out that when Duncan and his team did all this, the spectrum from their laboratory-created protonated naphthalene was almost identical to the spectrum seen in one part of the UIR.

What does it all mean? First, other scientists had found that interstellar dust is responsible for the production of molecular hydrogen from its atoms, which is the principal component of interstellar clouds. Other chemical processes taking place on the surface of dust grains are believed to form many molecules found on Earth, perhaps including the amino acids and peptides essential as the building blocks of life. And it is in these clouds that new stars form, so understanding how naphthalene fits into the equation (so to speak) of all this could provide insights into how stars and planetary systems form.

The new research also helps confirm earlier predictions that molecules called polycyclic aromatic hydrocarbons (PAHs) are the main source of the UIRs, since protonated naphthalene is a PAH.

"Protonated naphthalene itself does not explain all the UIR spectra," said Duncan, "but the characteristics of its spectrum suggest that a distribution of larger protonated PAHs could do this. The same spectral changes caused by the addition of protons to these larger systems would likely explain all the UIR patterns, thus ending one of the oldest mysteries in astronomy." Duncan and his group are now working to make and study these larger protonated PAHs.

Duncan's success in simulating the conditions of deep space in the lab and capturing that elusive proton could also have a payoff in studying other components of stellar clouds too.

Philiip Lee Williams | EurekAlert!
Further information:
http://www.uga.edu

More articles from Physics and Astronomy:

nachricht What happens when we heat the atomic lattice of a magnet all of a sudden?
18.07.2018 | Forschungsverbund Berlin

nachricht Subaru Telescope helps pinpoint origin of ultra-high energy neutrino
16.07.2018 | National Institutes of Natural Sciences

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: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>