II.

Discovery of Uranus

Sir William Herschel, a German-born British musician and astronomer, discovered the planet in 1781 with a telescope he built himself. Herschel accidentally discovered the new planet while measuring shifts in the positions of stars in the constellation Gemini. He observed that Uranus is a moving object, so he first reported his discovery to the British Royal Society as a comet. However, people had observed and plotted Uranus on star charts dating back to 1690 (believing it was a star). Uranus is so faint that people did not consider it important enough to include among the stars outlining the familiar constellations. Astronomers used these earlier observations to identify the object as a planet and to establish its orbit. Herschel originally named the planet Georgium Sidus (Star of George) in honor of King George III of Great Britain. Later, astronomers named the planet after Uranus, a figure who embodied the heavens and was the father of Saturn and the grandfather of Jupiter in Greek and Roman mythology.