About William Parsons, 3rd Earl of Rosse
William Parsons, 3rd Earl of Rosse, was an English engineer and astronomer. He built several giant telescopes. His 72-inch telescope, built in 1845 and colloquially known as the "Leviathan of Parsonstown", was the world's largest telescope, in terms of aperture size, until the early 20th century. From April 1807 until February 1841, he was styled as Baron Oxmantown. Lord Rosse performed astronomical studies and discovered the spiral nature of some nebulae, today known to be spiral galaxies. Richard Clere Parsons (21 February 1851 – 26 January 1923), apparently known for developing railways in South America. Sir Charles Algernon Parsons (13 June 1854 – 11 February 1931), known for inventing the steam turbine.
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