Great Canadian Flag Debate on December 15, 1964. It resulted in the adoption of the "Maple Leaf" as the Canadian national flag. The flag was inaugurated on February 15, 1965, and since 1996, February 15 has been commemorated as National Flag of Canada Day. For much of its post-Confederation history, Canada used both the Royal Union Flag (Union Jack) as its national flag, and the Canadian Red Ensign as a popularly recognized and distinctive Canadian flag. The first Canadian Red Ensigns were used in Prime Minister Sir John A. Macdonald's time. The Governor General at the time of Macdonald's death, Lord Stanley, wrote to
Great Debate (astronomy) format of the great debate has been used subsequently to argue the nature of fundamental questions in astronomy. In honor of the first "Great Debate", the Smithsonian has hosted four more events. Great Debate (astronomy) The Great Debate, also called the Shapley–Curtis Debate, was held on 26 April 1920 at the Smithsonian Museum of Natural History, between the astronomers Harlow Shapley and Heber Curtis. It concerned the nature of so-called spiral nebulae and the size of the universe; Shapley believed that distant nebulae were relatively small and lay within the outskirts of Earth's home galaxy, while Curtis held that they