Abstract

Resolving Nebulae – Life in Sight! While in the second half of the 19th century astrospectroscopy and ‐photography had contoured new objects of investigation like nebulae, the debate among astronomers about extraterrestrial life intensified. Images did not only play a key role in uprising popular astronomical magazines at that time, they also served as arguments or even as evidence in controversial debates about the nature of nebulae or of planets' surfaces. These debates were not restricted to academic astronomers, on the contrary, amateurs and popularisers were among the most active disputants. Photos and images published in popular magazines were more intensively retouched or manipulated than when they were used in academic communication about astronomy. But the practices of interpretation and speculation, based on drawings and images, stemmed from academic communities. Far reaching conclusions relying on unclear features of astronomical pictures, like in the case of Martian canals, have not only been criticised by other academics. History shows that the ability to scrutinise imaginations about evidence of life in space or about the forming of the solar system was due more to tacitly knowing how images were produced than to having an encyclopaedic recall in astronomy.