TWO long-overlooked Scottish astronomers whose achievements helped establish Scotland’s reputation in stargazing are to be recognised by having blue plaques unveiled in their honour.
Thomas James Henderson, (1798-1844) the first Astronomer Royal for Scotland, won the 1830s version of the “space race” by becoming the first scientist to measure the distance to a star.
Thomas David Anderson (1853-1932), a wealthy amateur astronomer, discovered two novae (exploding stars).
They will be commemorated by the Institute of Physics in Scotland (Iops) on 8 October.
Both astronomers lived in Edinburgh during significant parts of their career and the plaques will be placed at their former homes at 1 Hillside Crescent and 21 East Claremont Street, respectively. Born in Dundee, Henderson trained as lawyer before pursuing astronomy and mathematics. After a stint of working at the Royal Observatory at the Cape of Good Hope in South Africa, he was forced to return to Scotland due to ill-health.
Henderson analysed calculations he had made in South Africa to measure the distance to Alpha Centauri, the major component of the nearest star system to Earth. Doubts about the accuracy of his instruments delayed him publishing his results and consequently he is jointly credited with the discovery with German mathematician Friedrich Wilhelm Bessel.
Henderson worked at the City Observatory on Calton Hill and is buried in Greyfriars Kirkyard in the city.
Anderson, who was born in Edinburgh, studied theology but abandoned plans for the ministry to pursue astronomy full time. His most significant achievements were discovering the novas Aurigae 1892 and Persei 1901.
Professor John Brown, the tenth Astronomer Royal for Scotland, who will be unveiling both plaques at the ceremony, said: “Very few astronomers are honoured by the Institute of Physics so this will be an incredibly important day. Thomas Henderson made one of the biggest breakthroughs in astronomy at the time, but he was a canny Scot and delayed publishing his results. It is widely acknowledged Henderson was first to do the calculations.”
Regarding the plaques’ unveiling, National officer for Iops Alison McLure said: “It is really to highlight how strong astronomy has been in Scotland and also its vibrancy today. Henderson was the first Astronomer Royal for Scotland but a number of discoveries were made by amateur astronomers too, such as Thomas David Anderson. Science was done in a different way in the past with some of the best work done by amateurs.”
Iops has four blue plaques in Scotland: Lewis Fry Richardson (1881-1953); CTR Wilson, Nobel Laureate (1869-1959); Lord Kelvin (1824-1907); and Prof Sir George Paget Thomson, Nobel Laureate (1892-1975).