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A tilted gray ring of dust surrounds a star that looks like a bright yellow circle. Smaller distant stars dot the darkness of space.
NASA/JPL-Caltech

This Oct. 4, 2017, illustration shows a hypothetical uneven ring of dust orbiting KIC 8462852, also known as Boyajian’s Star or Tabby’s Star. The star has experienced unusual dips in brightness over a matter of days, as well as much subtler but longer-term dimming trends. Scientists proposed several explanations for this unexpected behavior, ranging from Tabby’s Star swallowing a planet to alien “megastructures” harvesting the star’s energy. However, a study using NASA’s Spitzer and Swift missions as well as the Belgian AstroLAB IRIS observatory suggests that the cause of the dimming over long periods is likely an uneven dust cloud moving around the star.

Learn more about this enigmatic star, named after Tabetha Boyajian, the Yale University postdoc who discovered it with the help of citizen scientists.

Image credit: NASA/JPL-Caltech

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      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 Letters.
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      Last Updated Jan 13, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
      Astrophysics Binary Stars Goddard Space Flight Center James Webb Space Telescope (JWST) Nebulae Science & Research Stars The Milky Way The Universe View the full article
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