This book tells the story of the Mt Stromlo Observatory in Canberra which began life as a government department, later becoming an optical munitions factory producing gun sights and telescopes during the Second World War, before changing its focus to astrophysics – the new astronomy. In the ensuing years programs were introduced to push the Observatory in new directions at the international frontiers of astronomy. The astronomers built new, better and larger telescopes to unravel the secrets of the universe. There were controversies, exciting new discoveries and new explanations of phenomena that had been discovered.