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Astronomers Rule Out Starburst Galaxies as Contributing to the Far-Ultraviolet Background


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Astronomers using the Hopkins Ultraviolet Telescope (HUT), flown aboard the Shuttle ASTRO-2 mission, have been able to exclude one explanation for the mysterious far ultraviolet background radiation that existed when the universe was young. They find that starburst galaxies -- galaxies forming new stars at an extremely high rate -- were largely opaque to the UV radiation from hot newborn stars embedded within them. Contrary to earlier ideas, this means that starburst galaxies did not contribute significantly to heating, or ionizing, the early universe.

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      Downloads
      Right click any image to save it or open a larger version in a new tab/window via the browser’s popup menu.
      View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
      View/Download the research results from the Astrophysical Journal .
      Media Contacts
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      Details
      Last Updated Aug 26, 2024 Editor Stephen Sabia Contact Laura Betz laura.e.betz@nasa.gov Related Terms
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      Downloads
      Right click any image to save it or open a larger version in a new tab/window via the browser’s popup menu.
      View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
      Media Contacts
      Laura Betz – laura.e.betz@nasa.gov, Rob Gutro – rob.gutro@nasa.gov
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
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