15 November

1738: On 15 November 1738, Sir William Herschel was born.

Herschel was a German-born British astronomer. In 1773, he made and began using his first telescope. With it he began a project that would continue for the rest of his life: that of systematically studying the sky. Through this study he discovered the planet Uranus, many new nebulae, clusters of stars and binary stars.

Herschel hypothesised that nebulae are composed of stars, developed a theory of stellar evolution and was the first person to correctly describe the form of our galaxy, the Milky Way. He discovered the Saturnian satellites Mimas and Enceladus and the Uranian satellites Titania and Oberon.