The year 2009 was declared to be the International Year of Astronomy and Cape Breton was part of the celebrations. The first observatory for viewing the planets and stars in Canada was built here in 1750. The astronomer Marquis de Chabert was commissioned to go to North America to correct the maps of the coasts of Cape Breton, Nova Scotia and Newfoundland. Chabert had to determine the longitude of Louisbourg and other locations in Cape Breton but he also recorded observations on the stars and the moon, as well as the tides and the climate. Within two years of his return to France, the French Royal Academy published Chabert’s book documenting his findings in Cape Breton. Chabert had led a well-financed and sophisticated scientific delegation to Cape Breton. Besides stellar observations throughout the island, he had constructed a timber built astronomical observatory that had windows, doors, locks and board siding. His instruments included eight telescopes. Six were refracting telescopes with focal lengths between 3 and 18 feet. There was also a Gregorian reflecting telescope with a focal length of 3 feet as well as a telescope for measuring angles. The observatory also had a seconds clock, terrestrial globes, maps of the stars and an octant. Ken Donovan’s presentation, based on extensive publication, discusses astronomy, navigation and map making in 18th century Cape Breton.