Mar 21, 2019
Photograph of star-field centred on the star Gamma Cassiopeia taken on 17 January 1890 with an exposure of 90 minutes. Dr Isaac Roberts, an amateur astronomer and pioneer astrophotography, took this image using a 20 inch aperture reflecting telescope. Made by Howard Grubb of Dublin, the telescope was first installed at his home near Liverpool, but later in 1890 he moved it to the less smoky skies of Crowborough, Sussex. In 1887, Roberts was invited to attend 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.