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Orbital precession
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Mercury's orbit precesses faster than Newton predicts, explained by general relativity.
Mercury's perihelion advances by 574″/century; Newtonian effects of other planets explain 531″, and general relativity adds the missing 43″.
This was an early test of general relativity.
Extra effects come from curved space.
In more detail
Orbital precession is the slow rotation of an orbit's elliptical shape. In Mercury's case, general relativity explains the extra precession that Newtonian gravity cannot.
Real-world uses
- Mercury's perihelion precession was a key test of general relativity.
- Binary pulsars show orbital precession that confirms relativity.
- Tests of general relativity measure the extra precession of Mercury's orbit, a result Newton's theory cannot explain.
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Frequently asked questions
How much does Mercury's orbit precess?
About 43 arcseconds per century beyond Newtonian predictions.
Why was it important?
It was one of the first successful tests of general relativity.
How much extra precession is there for Mercury?
About 43 arcseconds per century, which general relativity predicts exactly.
Related topics in Gravitation & Orbits
Gravitational self-energy · Inertial vs gravitational mass · Equivalence principle · Galaxy and cosmic structure · Space elevators and tethers · Gravity on other planets