Color enhanced illustration of a telescope, the largest of its time, built by German-British astronomer Sir Frederick William Herschel (1738-1822). He discovered the planet Uranus in 1781, resulting in his appointment as private astronomer to King George III of England. He financed the construction of a 50 cm telescope with which he discovered two moons of Uranus (Titania and Oberon) and two of Saturn (Mimas and Enceladus). In 1783 he discovered the intrinsic motion of the sun through space.