The Dominion Observatory was an astronomical observatory in Ottawa, Canada that operated from 1902 to 1970. The Observatory was also an institution within the Canadian Federal Government. The observatory grew out of the Department of the Interior's need for the precise coordinates and timekeeping that at that time could only come from an observatory. For several years they had used a small observatory on the Ottawa River for this purpose. In 1902, it was decided that Canada needed a larger national observatory similar to the Royal Greenwich Observatory in Britain.