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Astronomers have assembled the first definitive detection of a background infrared glow across the sky produced by dust warmed by all the stars that have existed since the beginning of time. For scientists, the discovery of this "fossil radiation" is akin to turning out all the lights in a bedroom only to find the walls, floor, and ceiling aglow with an eerie luminescence.

The telltale infrared radiation puts a limit on the total amount of energy released by all the stars in the universe. Astronomers say this will greatly improve development of models explaining how stars and galaxies were born and evolved after the Big Bang. These three pictures are maps of the full sky as seen in infrared light. The top picture represents the brightness of the full sky as seen in infrared light. The middle picture is a view of the sky after the foreground glow of the solar system dust has been extracted. After the infrared light from our solar system and galaxy has been removed, what remains is a uniform, cosmic, infrared background.

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      Media Contact:
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      202-358-2546
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      NASA Headquarters, Washington
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      Details
      Last Updated Aug 25, 2025 Related Terms
      Astrophysics Exoplanet Atmosphere Exoplanets Galaxies, Stars, & Black Holes Galaxies, Stars, & Black Holes Research Goddard Space Flight Center Kepler / K2 Stars TESS (Transiting Exoplanet Survey Satellite) The Universe View the full article
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      Details
      Last Updated Jul 17, 2025 Editor Lonnie Shekhtman Contact Lonnie Shekhtman lonnie.shekhtman@nasa.gov Location NASA Goddard Space Flight Center Related Terms
      Planetary Science Planets The Solar System Uranus View the full article
    • By European Space Agency
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