In this edition of Treasures of the RAS, Librarian Jenny Higham introduces the notebooks of William Herschel, describing his discovery of Uranus in 1781.
Herschel recorded his observations of a new planet in his working notebook of March 1781: "a curious either nebulous star or perhaps a comet", near the star Pollux.
Later observations demonstrated that this was the first new planet discovered since prehistoric times.
Herschel attempted to name the planet 'Georgium sidus' (George's star) after King George III. Although this brought him great favour with the King, the name was unpopular outside Britain. Later agreement called the planet 'Uranus'.