Unwrapping the Visual Discovery of Spiral Nebulae

Join visual observer Steve Gottlieb for an intriguing talk onUnwrapping the Visual Discovery of Spiral Nebulae.  This is the story of William Parsons' (Lord Rosse) first visual observations of M51 with his massive 72-inch speculum reflector in the spring of 1845 and the subsequent discovery of spiral structure in dozens of "nebulae".  Gottlieb will discuss how our pre-conceived notions and knowledge of the nature of the objects we view in the telescope affect our visual perception at the eyepiece. Beautiful eyepiece sketches of several spirals by Rosse and other mid-19th century observers will be presented.