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Light bending by the Sun
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Eddington's 1919 eclipse confirmed general relativity.
Starlight grazing the Sun bends by 1.75″, twice Newton's prediction. Eddington's 1919 eclipse observations supported Einstein.
Measured with radio telescopes to 0.01%.
Basis of gravitational lensing.
In more detail
General relativity predicts that light is bent by the gravity of massive objects. The bending of starlight near the Sun was confirmed during the 1919 solar eclipse.
Real-world uses
- Gravitational lensing uses this effect to study distant galaxies.
- The 1919 measurement helped establish general relativity.
- Astronomers observed the bending of starlight near the Sun during the 1919 eclipse, which confirmed general relativity.
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Frequently asked questions
How much does the Sun bend light?
About 1.75 arcseconds for light grazing the Sun's surface.
Who led the 1919 test?
Arthur Eddington led expeditions to test the prediction.
Why was the 1919 eclipse important?
It was the first test that gave clear support to general relativity over Newtonian gravity, and it made Einstein famous.
Related topics in Relativity
Hawking radiation · Gravitational waves detection · Frame dragging · Cosmological redshift · Wormholes