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A three-dimensional map of the Milky Way using classical Cepheid variable stars

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 نشر من قبل Dorota Skowron
 تاريخ النشر 2018
  مجال البحث فيزياء
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The Milky Way is a barred spiral galaxy, with physical properties inferred from various tracers informed by the extrapolation of structures seen in other galaxies. However, the distances of these tracers are measured indirectly and are model-dependent. We constructed a map of the Milky Way in three-dimensions based on the positions and distances of thousands of classical Cepheid variable stars. This map shows the structure of our Galaxys young stellar population, and allows us to constrain the warped shape of the Milky Ways disk. A simple model of star formation in the spiral arms reproduces the observed distribution of Cepheids.



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