October 24, 1851
William Lassell discovers the moons Umbriel and Ariel (moon) orbiting Uranus.
Umbriel named after a character in Alexander Pope's poem The Rape of the Lock. Ariel named for a sky spirit in Alexander Pope's The Rape of the Lock and Shakespeare's The Tempest.
Rings of Uranus
March 10, 1977Astronomers discover rings around Uranus.
The planet Uranus has a system of rings intermediate in complexity between the more extensive set around Saturn and the simpler systems around Jupiter and Neptune. The rings of Uranus were discovered on March 10, 1977, by James L. Elliot, Edward W. Dunham, and Douglas J. Mink. More than 200 years ago, William Herschel also reported observing rings (in 1789); some modern astronomers are skeptical that he could have actually seen them, as they are very dark and faint – others are not.
March 13, 1781
William Herschel discovers Uranus.
Size comparison of Earth and Uranus
Uranus is the seventh planet from the Sun. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. It is named after the ancient Greek deity of the sky Uranus, the father of Cronus (Saturn) and grandfather of Zeus (Jupiter). Though it is visible to the naked eye like the five classical planets, it was never recognized as a planet by ancient observers because of its dimness and slow orbit. Sir William Herschel announced its discovery on March 13, 1781, expanding the known boundaries of the Solar System for the first time in modern history. Uranus was also the first planet discovered with a telescope.