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New Survey Finds that Single Burst of Star Formation Created Milky Way’s Central Bulge


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Like most spiral galaxies, the Milky Way has a roughly spherical collection of stars at its center called the bulge. How the bulge formed has been a long-standing mystery, with many studies suggesting that it built up over time through multiple bursts of star formation.

New research finds that the majority of stars in our galaxy’s central bulge formed in a single burst of star formation more than 10 billion years ago. To reach this conclusion, astronomers surveyed millions of stars across 200 square degrees of sky—an area equivalent to 1,000 full Moons. The resulting wealth of data is expected to fuel many more scientific inquiries.

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      News Media Contact
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      Chandra X-ray Center
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      617-496-7998
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      Corinne Beckinger
      Marshall Space Flight Center, Huntsville, Alabama
      256-544-0034
      corinne.m.beckinger@nasa.gov
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