Twin equatorial telescope, 1885.
© Science Museum / Science & Society Picture Library
Isaac Roberts (1829-1904), an amateur astronomer, used this telescope to take pioneering astronomical photographs from 1885. In October 1887 he took the first photograph showing the spiral form of the Andromeda Nebula; now known to be a nearby galaxy. Made by Howard Grubb in Dublin, Ireland, the masive mounting carries a reflecting telescope of 20 inch (508mm) aperture and a refracting telescope with a 7 inch (178mm) diameter lens. First installed at Robert's home near Liverpool, it was later moved to the les smoky skies of Crowborogh, Susex. In 1887, Roberts attended the first international conference in Paris on celestial photography. Here, astronomers decided to embark on the 'Carte du Ciel', an ambitious project to photograph the whole sky in unprecedented detail.