When was Uranus discovered?
Short answer: March 13, 1781
Long answer: Although the planet Uranus had been seen many times throughout history, it was assumed to be a faint star. it was not until 1781 that it was recognized as a planet.
The discovery of Uranus came by accident. British astronomer Sir William Herschel on March 13, 1781 was conducting a "survey of stars" which basically means making a map of them. He noticed a very faint object—just barely visible to the naked eye—that move differently to the surrounding stars. Initially he thought it was a comet but he later realized that it was the first new planet discovered since prehistoric times.
William Herschel’s enormous 40-foot (12-meter) telescope. Herschel made this himself between 1785 and 1789. For half a century it stood as the largest telescope in the world.
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