Celebrate science at David Dunlap Observatory

Celebrate more than 90 years of science and outreach conducted at the Richmond Hill David Dunlap Observatory (RHDDO), one of Canada’s National Historic Sites and home of the largest telescope in Canada.

Numerous important studies have taken place at the RHDDO. Hear a presentation that explains in simple language how important discoveries, including Tom Bolton’s discovery of Cygnus X-1 – the first known black hole – were made. Historical records and artifacts involved in the discoveries will be on display. Viewing through the 74-inch telescope will be provided, weather permitting.

Participants under 16 years of age must be accompanied by an adult. Wear/take appropriate supplies for being outdoors and arrive 15 minutes before the program begins to be signed in. The event takes place Saturday, May 30 from 9 to 11 p.m., rain or shine. The RHDDO is located at 123 Hillsview Dr. Register here.

The property was the site of a 19^th-century farmstead owned by Alexander Marsh. When the observatory in downtown Toronto could no longer function due to light pollution, the University of Toronto identified the farmstead as being suitable for a new astronomical facility. As a result, Jessie Donalda Dunlap purchased the property and donated it to the University as a memorial to her husband, David Alexander Dunlap, who was an avid astronomer.

The University constructed the Observatory, which was at the forefront of Canadian astronomical research from 1935 to 2007. In June 2008, the University sold the property to Corsica Developments Inc. In 2012, Corsica transferred about half of the property to Richmond Hill for public park use and cultural heritage protection. In 2018, Richmond Hill opened the RHDDO to the community for astronomy programs and summer camps.