First of all some information abut the Planetarium:
- official website which is available only in italian as far as I can see
- wikipedia italian and english (unfortunately the english version is a bit poor in content at the time of writing)
So, what's a planetarium? It's a building with an hemispheric ceiling on which a powerful and sophisticated projector projects some shiny dots.
Those dots show the position and the movements of stars in the sky during the night and the day and during the seasons. Inside the room there are quite comfortable and robust wooden made spinning chairs for the visitors attending the show.
The planetarium in Milano also shows, at the bottom of the hemispherical ceiling, a proportionate skyline of Milano as it was seen in 1930. The skyline provides to the visitor some useful points of reference.