Earth & Space Science · 1929
A Relation Between Distance and Radial Velocity Among Extra-Galactic Nebulae
Edwin Hubble
Overview
Hubble showed that distant galaxies are receding from us at speeds proportional to their distance — the first observational evidence that the universe is expanding. The proportionality is now called Hubble's law.
Established cosmic expansion, the cornerstone of modern cosmology.
Key findings
Methods
Distances to galaxies were estimated from Cepheid variable stars and other indicators, then compared with their redshift-derived radial velocities to reveal a linear relationship.
Keywords
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