TIMELINES: What European astronomer discovered Uranus on March 13, 1781?

March 13, 2012 Updated: September 29, 2015

Tuesday, Mar. 13, 2012


March 13, 1781, astronomer William Hershel discovers Uranus. With the use of a telescope, the German-born Englishman is able to distinguish Uranus—the seventh planet from the Sun in our galaxy—as a planet rather than a star, as astronomers previously thought. Uranus is a gas giant planet similar to Jupiter and Saturn composed primarily of hydrogen, helium, and methane. Hershel decides to name his discovery Georgium Sidus, or the Georgian Planet, in honor of the King George III who is so taken with Hershel that Hershel is given a salary and residence near Windsor and is named his majesty’s own astronomer. Later, the planet becomes generally known as Uranus, proposed by German astronomer Johann Bode to conform to classical mythology-derived names of the other known planets in our galaxy.


Today, the William Hershel Telescope (WHT) located at the Observatorio del Roque de los Muchachos on the island of La Palma in the Canary Islands, is the second largest telescope in Europe and was the third largest in the world at the time of its construction in 1987. WHT is a 165-inch (4.20-meter) optical/near-infrared reflecting telescope. Modern astronomers used the telescope to discover the first evidence for a supermassive black hole at the center of the Milky Way, and to observe a gamma-ray burst.