William Edward Wilson, Irish astronomer, is born at Greenisland, County Antrim, on July 19, 1851. He is the only son of John and Frances Wilson of Daramona House, Streete, County Westmeath, and is privately educated.
Wilson becomes interested in astronomy and travels to Oran in 1870 to photograph the solar eclipse. In 1871 he acquires a reflecting telescope of 12 inches (30.5 cm) aperture and sets it up in a dome in the gardens of Daramona House. He uses it to experiment on the photography of the moon with wet plates and also begins to study solar radiation using thermopiles. In 1881, he replaces the original telescope with a Grubb reflector of 24 inches (61 cm) aperture and a new dome and mounting that has an electrically controlled clock drive. The new telescope is mounted in a two-story tower attached to the house with an attached physical laboratory, darkroom and machine shop.
Wilson’s main research effort, in partnership with P.L. Gray, is to determine the temperature of the sun using a “differential radio-micrometer” of the sort developed by C.V. Boys in 1889, which combines a bolometer and galvanometer into one instrument. The result of their measurements is an effective temperature of about 8000 °C for the sun which, after correction to deal with absorption in the earth’s atmosphere, give a value of 6590 °C, compared to the modern value of 6075 °C.
Some of Wilson’s other astronomical projects include observations on the transit of Venus, determination of stellar motion, observations of sunspots and a trip to Spain to photograph a solar eclipse. He takes a great many excellent photographs of celestial bodies such as nebulae. His astronomical findings are published in a series of memoirs such as Experimental Observations on the Effective Temperature of the Sun.
Wilson is elected a fellow of the Royal Astronomical Society in 1875 and a Fellow of the Royal Society in 1896. He receives an honorary doctorate (D.Sc.) from the University of Dublin in June 1901. He serves as High Sheriff of Westmeath for 1894.
Wilson dies on March 6, 1908 at Daramona at the relatively young age of 56, and is buried in the family plot in Steete churchyard. He had married Caroline Ada in 1886, the daughter of Capt. R.C. Granville, and they have a son and two daughters. His son donates his telescope to the University of London, where it is used for research and teaching, finally becoming a feature in Liverpool museum.