Inaugurated on the 20th May 1965, with the purpose of promoting interest in astronomy and scientific technology, the Portuguese people, who knew the world by looking at the stars, can contemplate the most faithful representation of the cosmos, with about 9000 visible stars of the two celestial hemispheres, the Milky Way and other galaxies.Milky Way and other galaxies. Besides the Planetarium Auditorium, the Planetarium also has a Gallery with several thematic exhibitions, an Observatory under renovation and a specific Library with more than 1000 titles.