This Day in History: 11 May 1871
On 11 May 1871 astronomer, Sir John Frederick William Herschel, died. Herschel began to take a serious interest in astronomy from about 1816. Herschel's father was the famous astronomer Frederick William Herschel, the discoverer of the planet Uranus.From 1816 Herschel began a collaboration with James South and re-observed the many double stars discovered during his father's survey of the northern sky from 1783-1803. With his father he cast, ground and polished a new 460 mm speculum mirror with a focal length of some 6 m and by 1820 had used it to construct one of the most powerful telescopes in use at the time. During the years 1825-1833 John used this instrument to repeat his father's survey of the northern hemisphere, confirming and adding to the nebulae and double stars. This work made him as prominent in astronomical circles as his father (who died in 1822) had been.In 1833 he decided to extend his comprehensive astronomical survey of double stars and nebulae to the southern hemisphere, using his own telescope. He chose the Cape of Good Hope as a base because of its relative accessibility and the presence there of the Royal Observatory, from which he could expect professional assistance. To read a full biography and details of Herschel's discoveries click here.Source: 1. S2A3 biographical database of southern African science, s2a3.up.ac.za/bio/Main.php, as on Tuesday 06 May 2008.