The history of astronomy is littered with misunderstandings, misconceptions and downright frauds. Tony Robert’s review of some of these made for an entertaining evening. Tony began with the plausible near-discovery of Vulcan – Mercury’s planetary sister. He went on to explore Herschel’s on-off “non-discovery” of Uranus’ rings. He touched on Galileo’s confusion of Saturn’s ring system with a pair of moons and how it was understandable with the very crude telescopes at his disposal.
The great “Moon Hoax” of 1835 was a successful fraud which exploited the fact that Sir John Herschel was observing in South Africa – weeks, if not months away from direct communication – to invent a whole civilisation on the moon that he was alleged to have discovered. Tony expanded on that deception to demonstrate how a desperate need to believe we were not alone in the universe led to Lowell’s Martian canals, and fantastic calculations of the population of the solar system, based on surface areas.
Tony’s diversions were at least as instructive – he explored how the designers of larger and larger telescopes tried to deal with optical anomalies; the use of aircraft to try to get telescopes into at least the upper atmosphere; how Kirchoff and Bunsens’ use of spectroscopy confounded received wisdom that we would never know what stars were made of; and the influence of Great Exhibitions on the competitive development of gigantic telescopes.