Editing David Dunlap Observatory (section)

===Shifting locations===
[[File:Photo Dunlap Observatory 1948 - Touring Club Italiano 07 0250.jpg|thumb|David Dunlap Observatory in 1948]]
With the rapid growth of university funding in the 1960s more offices were being built in the downtown campus, and with the opening of the McLennan Labs more and more of the department moved into the new facilities. The Administration Building at the DDO headquartered the Astronomy Department until the 1960s, although the weekly department meetings continued to be held there until 1978. The main library was shifted downtown in 1983. The Cooke Refractor, now almost unused, was later donated to the [[Canada Science and Technology Museum]] in 1984.{{sfn|Fernie|2000}}

The main reflector at the DDO remained a major instrument into the 1960s, but in the end even the "remote" location Chant had selected was being encroached on by [[urban sprawl]]. Although some consideration was given to moving the telescope to a new site, in the end it was decided the funds would be better spent on a smaller instrument in a much better location. This led to the building of a {{convert|60|cm|in|adj=on}} instrument at [[Las Campanas Observatory|Las Campanas]] in Chile in 1971, creating the [[University of Toronto Southern Observatory]] (UTSO). It was at this location that University of Toronto telescope operator [[Ian Shelton]] discovered [[Supernova 1987A]], the first supernova visible to the naked eye in more than 350 years.<ref name="iauc">{{cite web | url = http://www.cbat.eps.harvard.edu/iauc/04300/04316.html | title = IAUC4316: 1987A, N. Cen. 1986 | date = 24 February 1987}}</ref> The UTSO was closed in 1997 to re-allocate funds to a share of the [[Gemini Observatory]], and the {{convert|60|cm|in|adj=on}} telescope was moved to [[Leoncito Astronomical Complex|El Leoncito]] in Argentina, where the university has a 25% share in observation time.{{sfn|Fernie|2000}} While University operations continued at the DDO, international observers used about 50% of observing time there.