The Observatory is not only multiple by its sites, it is also multiple by the fields of study which are developed there. Theorists, observers and instrumentalists use there mathematical, physical and chemical tools, digital simulations and experiments of laboratory to develop researches which cover almost all the fields of astronomy and astrophysics.

Astronomy played an unquestionable part in the history of humanity. What would have been the economic development without the ocean navigation which allowed the location of stars? And doesn't the development of the ideas have much to do with the questioning of the Earth as the center of the Universe, which largely contributed to fissure the immutability of many dogmas?

But science evolves and the society becomes more and more complex, and the relationship between these two entities changes together with history. The universe has become a true laboratory which is not only used to test different unverifiable physical laws, but also makes it possible to discover new laws. On the technological level, the astronomers are users of techniques resulting from other fields and for this reason have their place in economy. But they also contribute, because of their own requirements, to develop techniques which in their turn will be useful elsewhere. Astronomy is not only a "pure" science: it prepares the future and unavoidable conquest of the solar system (at the 21st century?). On a more practical level, it contributes to the knowledge of the astronomical factors of evolution of the climate and to the monitoring still stammering of possible dangers of cosmic origin.