Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A jet of molecular hydrogen arising from a forming high-mass star

07.03.2007
A team of European astronomers offer new evidence that high-mass stars could form in a similar way to low-mass stars, that is, from accretion of gas and dust through a disk surrounding the forming star.

Their article, published in Astronomy & Astrophysics, reports the discovery of a jet of molecular hydrogen arising from a forming high-mass star located in the Omega nebula (M17). This detection confirms the hypothesis based on their earlier discovery that this forming high-mass star is surrounded by a large accretion disk.

While astronomers now understand the overall process of low-mass star formation very well, the formation process of massive stars is still very much under debate. Recent astronomical observations suggest that high-mass stars [1] could form through accretion processes, just like low-mass stars do. For instance, in 2004, European astronomers discovered a large accretion disk that probably surrounds a forming high-mass star, in the star-forming region M17, also known as the Omega nebula and located at a distance of about 7000 light years [2].

Looking again at M17 with the new spectrograph SINFONI [3] at the ESO-VLT, the same European group [4] report discovering a jet of molecular hydrogen (H2) that apparently arises from the forming high-mass star. The picture below illustrates this discovery, which is being published in Astronomy & Astrophysics.

The ejection of material through a jet or an outflow is always linked to accretion of gas and dust, either onto the circumstellar disk or onto the central protostar. The detection of the H2 jet thus provides evidence that ongoing accretion processes occur in the M17 disk. The team also estimates the mass outflow and mass accretion rates, which suggest that a star of high mass is forming within the M17 disk. This is an additional clue that high-mass stars form in a similar way to lower mass stars.

[1]A high-mass star is a star of more than 8 times the solar mass.

[2] For information about this earlier discovery, see the ESO press release and the article published in the ESO Messenger.

[3] SINFONI (for "Spectrograph for INtegral Field Observation in the Near-Infrared") is one of the most recent instruments installed at the ESO-VLT. Associated to an adaptive optics module, it provides very high-angular resolution spectra and images. Technical details and first results can be found on the ESO web site.

[4] The team includes D.E.A. Nürnberger (ESO), R. Chini (Ruhr-Universität Bochum, Germany), F. Eisenhauer (MPE, Garching, Germany), M. Kissler-Patig, A. Modigliani, R. Siebenmorgen, M.F. Sterzik, T. Szeifert (ESO). Full article available at: http://www.aanda.org/index.php?option=com_content&task=view&id=218&Itemid=42&lang=en

Jennifer Martin | alfa
Further information:
http://www.obspm.fr
http://www.aanda.org/index.php?option=com_content&task=view&id=218&Itemid=42&lang=en

More articles from Physics and Astronomy:

nachricht Computer model predicts how fracturing metallic glass releases energy at the atomic level
20.07.2018 | American Institute of Physics

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

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: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

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....

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

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

Computer model predicts how fracturing metallic glass releases energy at the atomic level

20.07.2018 | Physics and Astronomy

Relax, just break it

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>