It had, for its time, a state-of-the-art electro-mechanical Zeiss planetarium projector that was used to project regular themed shows about the stars, planets, and cosmology for visitors.

The lower levels of the planetarium contained a gallery called the "Astrocentre" that featured space-related exhibits, related artifacts on the history of astronomy and was also home of the world's first commercial Stellarium[1] Starting in 1978, there was a decline in attendance that lasted for four years while major construction was being undertaken at its sibling institution, the adjacent Royal Ontario Museum.

[6] Proposals for building a planetarium in Toronto date back to 1944, but serious planning only started in 1962, thanks to a bequest made by a former member of the Royal Astronomical Society of Canada (RASC).

In November 1964 Canadian businessman Colonel Samuel McLaughlin announced plans for donating money directly towards establishing a planetarium in Toronto.

Colonel McLaughlin unveiled a model of the building at his 94th birthday celebration, which was held in his honour at the museum in September of that year.

[2] In addition to what was built, the original plans also called for a multi-story parking garage, a 550-seat conventional movie theatre, and a direct underground link to the Museum subway stop.

It was a Universal Projection Planetarium type 23/6, made by Kombinat VEB Carl Zeiss in Jena, in what was then East Germany.

[11] The planetarium projector was a 13-foot (4.0 m)-long dumbbell-shaped object, with 29-inch (740 mm)-diameter spheres attached at each end representing the night sky for the northern and southern hemispheres.

[15] When plans were drawn up for a major expansion of the adjacent Royal Ontario Museum in the mid-1970s, it was initially assumed that the planetarium, then still a comparatively new facility, would be left untouched.

As a result, a theatre entrance, sound studio, workshop, passenger elevator and a third of the existing gallery area of the planetarium had to go.

Significant changes to the planetarium were made during this time, including the addition of a new spiral staircase that led straight to the Theatre of the Stars, an adjacent elevator for the elderly and disabled, and a larger gallery space on the second floor.

[10] Some of the automated "star shows" that appeared in this time interval include: "Planets, Stars, and Galaxies", a general show about our knowledge of astronomy at the time; "Mars, the Journey Begins", the story of the exploration of Mars (from prehistory to the then-present), and possible future plans for terraforming Mars; "Beyond the 4th Dimension", which explored, in layman's terms, the 4 dimensions of General Relativity, the Big Bang and inflation, and the new (at the time) theories of physics that postulated that space has up to 11 dimensions; some of these shows featured creative and novel sound tracks composed by composer-in-residence Mychael Danna.

The Astrocentre also featured the world's first commercial Stellarium, a slowly rotating display containing a 3D representation of almost a thousand stars in our immediate stellar neighbourhood.

[17][18] The decision came as a surprise to many, as attendance had rebounded in recent years, and the planetarium was one of few in North America at the time that was turning a profit.

The original Zeiss-Jena projector was bought as a museum piece by York University for the sum of $1, subsequently dismantled, and placed into storage.

On March 5, 1998, an initial three-year agreement was signed that brought the Children's Own Museum to the second floor of the planetarium, where the Astrocentre used to be.

Later in 2002, a traveling exhibit of costumes, props and models used in the making of Peter Jackson's Lord of the Rings trilogy ran for four weeks at the planetarium.

It was to include the Jewish Museum of Canada, a Faculty of Music performance hall, research centres and History department academic space.

[27] In January 2016, the university announced it would proceed with construction of what is now to be called the Centre for Civilizations and Cultures, without the participation of the Jewish Museum of Canada because the UJA "needed to focus on more pressing funding priorities."

She reports to her father, who is on his deathbed in a Toronto hospital, that she enjoyed the show but found the planetarium to be "a slightly phony temple" to the stars.

[29] In the opening chapter of Robert J. Sawyer's 2000 science fiction novel Calculating God, an alien spaceship lands directly in front of the McLaughlin Planetarium, prior to going on a tour of the exhibits in the Royal Ontario Museum.