The Hubble Constant

  title={The Hubble Constant},
  author={Wendy L. Freedman and Barry F. Madore},
  journal={Annual Review of Astronomy and Astrophysics},
Considerable progress has been made in determining the Hubble constant over the past two decades. We discuss the cosmological context and importance of an accurate measurement of the Hubble constant, focusing on six high-precision distance-determination methods: Cepheids, tip of the red giant branch, maser galaxies, surface brightness fluctuations, the Tully-Fisher relation, and Type Ia supernovae. We discuss in detail known systematic errors in the measurement of galaxy distances and how to… 
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The cosmic distance scale and H0: Past, present, and future
  • W. Freedman
  • Physics
    Proceedings of the International Astronomical Union
  • 2012
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