Each day we feature a different image or photograph of our fascinating universe, along with a brief explanation written by a professional astronomer. The distance to the swirling grand design spiral M100 is causing quite a stir among astronomers. Many believe that the Hubble Space Telescope 's recent distance measurement to this galaxy accurately calibrates the expansion rate of the universe . Others believe this distance measurement is misleading. Scientific debate over the value of Hubble's constant has been ongoing since it was first measured by Edwin Hubble in 1929.
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