HUBBLESLAW
Hubble's law
Hubble's law is the name for the observation in physical cosmology that: objects observed in deep space are found to have a Doppler shift interpretable as relative velocity away from the Earth; and that 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.The above text is a snippet from Wikipedia: Hubble's law
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