William Parsons, 3rd Earl of Rosse
William Parsons, 3rd Earl of Rosse, was an Irish astronomer, naturalist, and engineer. He was president of the Royal Society (UK), the most important association of naturalists in the world in the nineteenth century. 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.
William, 3rd Earl of Rosse
Drawing of the Whirlpool Galaxy by Rosse in 1845
Lord Rosse
The largest telescope of the 19th century, the Leviathan of Parsonstown.
Leviathan of Parsonstown, or Rosse six-foot telescope, is a historic reflecting telescope of 72 inches (1.83 m) aperture, which was the largest telescope in the world from 1845 until the construction of the 100-inch (2.5 m) Hooker Telescope in California in 1917. The Rosse six-foot telescope was built by William Parsons, 3rd Earl of Rosse on his estate, Birr Castle, at Parsonstown in Ireland.
Victorian picture of the "Leviathan of Parsonstown"
A 1:24 model of the telescope made by Parsons in 1844-45.
Reconstructed telescope seen from a distance
The Irish low-frequency array (I-LOFAR) radio telescope in the castle grounds.