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Astronomy

Testing General Relativity Through the Precession of Mercury's Orbit

Quick fact

Before Einstein, astronomers had measured that Mercury's orbit precesses by 574 arcseconds per century, but Newtonian physics could only explain about 531 arcseconds of that. Einstein's general relativity elegantly accounted for the missing 43 arcseconds.

Why this is interesting

You've probably heard that Einstein's theory changed everything, but how do you actually test a theory of gravity? It turns out a tiny wobble in Mercury's orbit helped prove him right.

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Testing General Relativity Through the Precession of Mercury's Orbit

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