The society is devoted to the promotion and advancement of knowledge of the universe through research and education, and its membership is open to people with a professional involvement in astronomy and related sciences.
Canadians also held leadership positions and attended meetings of the American Astronomical Society (AAS).
Canada was also an early member of the International Astronomical Union, with activities coordinated through the Dominion Observatory.
In the 1960s, university programmes in science expanded rapidly and astronomy groups and departments appeared across Canada.
CASCA was founded in May 1971 by a committee of the Canadian government's National Research Council and Helen Sawyer Hogg was elected as the first president.