Edwin Powell Hubble (1889-1953)

Hubble's law is the name for the observation in physical cosmology that:

  1. Objects observed in deep space - extragalactic space, 10 megaparsecs (Mpc) or more - are found to have a red shift, interpreted as a relative velocity away from Earth;
  2. This Doppler shift-measured velocity, of various galaxies receding from the Earth, is approximately proportional to their distance from the Earth for galaxies up to a few hundred megaparsecs away.[1][2]

Hubble's law is considered the first observational basis for the expansion of the universe and today serves as a form of evidence for the birth of the universe at a singularity.[3][4] The motion of astronomical objects due solely to this expansion is known as the Hubble flow.[5]

See alsoEdit


  1. Riess, A. (September 1998). "Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant". The Astronomical Journal 116 (3): 1009–1038. doi:10.1086/300499. Bibcode1998AJ....116.1009R. 
  2. Perlmutter, S. (June 1999). "Measurements of Omega and Lambda from 42 High-Redshift Supernovae". The Astrophysical Journal 517 (2): 565–586. doi:10.1086/307221. Bibcode1999ApJ...517..565P. 
  3. Overbye, Dennis (20 February 2017). "Cosmos Controversy: The Universe Is Expanding, but How Fast?". New York Times. Retrieved 21 February 2017. 
  4. Coles, P., ed (2001). Routledge Critical Dictionary of the New Cosmology. Routledge. p. 202. ISBN 0-203-16457-1. 
  5. "Hubble Flow". The Swinburne Astronomy Online Encyclopedia of Astronomy. Swinburne University of Technology. Retrieved 2013-05-14.