Discovery · 1929 CE
The Expansion of the Universe
History of Astronomy
Overview
Using Cepheid distances and galaxy redshifts, Edwin Hubble showed in 1929 that galaxies recede faster the farther away they are — the universe is expanding, as Lemaître had derived two years earlier.
Why it matters
The observational foundation of modern cosmology and the Big Bang.
Credit
Objects & facilities
Bearing on theory
Knowledge connections
- Discovered byEdwin Hubble
- Predicted byGeorges Lemaître
- Part ofModern Astronomy
- Related toAndromeda Galaxy
- Related toThe Milky Way
- Discovered atMount Wilson Observatory
- ConfirmedThe Big Bang
- Related toThe Big Bang
- Related toThe Expansion of the Universe
- Related toThe Hubble–Lemaître Law
Sources & references
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.
- BritannicaEncyclopaedia Britannica
General reference for the history of astronomy, biographies, and cultural context.