The Planetarium of Cortina, opened in December 2009, has been named after to Alessandro Dimai, great amateur astronomer, science popularizer, supernovae dicoverer, who in the last 30 years had completely dedicated himself to the study, research and dissemination of astronomy. The dedication ceremony took place on Saturday May 11, 2019. Alessandro presented to the public the structure inaugurated on December 12, 2009.

In the Planetarium are shown the motions of the sky, the Sun, the Moon and planets, constellations, deep sky objects and simulations of past and future astronomical events. Spectacular "full-dome" movies of the Solar System and  black holes are projected also and, for children, a trip with the Space Shuttle is simulated.

The Planetarium "Alessandro Dimai", with a diameter of 8.4 meters and a capacity of 60 people, is big enough for Cortina and its tourists.