National Radio Astronomy Observatory - 26 May 2010
Discovery provides new information about structure, chemical composition of hour home Galaxy
Astronomers studying the Milky Way have discovered a large number of previously-unknown regions where massive stars are being formed. Their discovery provides important new information about the structure of our home Galaxy and promises to yield new clues about the chemical composition of the Galaxy.
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The star-forming regions the astronomers sought, called H II regions, are sites where hydrogen atoms are ionized, or stripped of their electrons, by the intense radiation of the massive, young stars. To find these regions hidden from visible-light detection by the Milky Way's gas and dust, the researchers used infrared and radio telescopes.
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Further analysis allowed the astronomers to determine the locations of the H II regions. They found concentrations of the regions at the end of the Galaxy's central bar and in its spiral arms. Their analysis also showed that 25 of the regions are farther from the Galaxy's center than the Sun.