Herschel's nebulae observations. Page of written observations of nebulae made on 3 and 15-17 April 1786 by the Anglo-German astronomer William Herschel (1738-1822). Herschel, who built his own telescopes from 1773, made his first notes on 1 March 1774. This started a distinguished astronomical career which included the discovery of the planet Uranus. These are his 'swweps' observations, where he swept the entire sky checking for nebulae missed in earlier observations. Eventually, these nebulae would be recognised as entire galaxies.