The Brussels Planetarium (French: Planétarium de Bruxelles; Dutch: Planetarium van Brussel) of the Royal Observatory of Belgium is a planetarium located on the Heysel/Heizel Plateau in Laeken (northern part of the City of Brussels).

It was established during the Brussels International Exposition of 1935 as the Alberteum and is now part of the institutions of the Belgian Federal Science Policy Office (BELSPO).

The planetarium has an international scientific reputation, and is one of the largest in Europe, with its dome of 23 metres (75 ft) in diameter,[1] on which the Sun, the Moon, the planets, the Milky Way and more than 8,500 stars can be projected.

[2] In April 2021, the planetarium opened its newly renovated dome, equipped with eight state-of-the-art Barco projectors.

The projectors were installed by RSA Cosmos, who also provided the latest version of its powerful astronomical software, SkyExplorer 2021.