The cosmic microwave background is a faint glow of microwave radiation that fills the whole sky and is the oldest light that can be observed, released about 380,000 years after the Big Bang when the universe cooled enough for atoms to form. It was found by accident in 1964 by Arno Penzias and Robert Wilson, two radio astronomers at Bell Laboratories in New Jersey, who were trying to remove persistent noise from a sensitive horn antenna. A team at Princeton led by Robert Dicke had been preparing to search for the radiation, which had been predicted by theorists. The discovery was strong evidence for the Big Bang model over rival steady-state theories, and Penzias and Wilson shared the 1978 Nobel Prize in Physics. Satellites such as COBE, WMAP and Planck have since measured its temperature, about 2.7 kelvin, and its tiny variations.
Before and after
- 19 February 1964Birth of Jennifer Doudna
- 25 February 1964Muhammad Ali beats Sonny Liston
- 9 March 1964Birth of Juliette Binoche
- 7 April 1964Birth of Russell Crowe
- 20 May 1964Cosmic microwave background
- 27 May 1964Death of Jawaharlal Nehru
- 27 May 1964Colombian conflict
- 1 June 1964Establishment of Shiretoko National Park
- 15 June 1964Founding of Group of 77
More in Science & technology
- 25 April 1953Watson and Crick publish the structure of DNA
- 14 February 1961Discovery of lawrencium
- 20 November 1985Creation of Microsoft Windows
- 1996Discovery of copernicium
- August 2003Discovery of moscovium
- 2006Discovery of nihonium
The era
This moment belongs to the Contemporary world (1945 CE to today), the world since 1945. You can also browse everything in the 20th century.