Founded in 1667, the Paris Observatory-PSL is a major player in astronomy and astrophysics research. For nearly 360 years, it has contributed to our understanding of the Universe and to the development of related sciences and technologies.
With 750 researchers, faculty members, engineers, and staff spread across three campuses— Paris, Meudon, and Nançay, the institution conducts research at the intersection of theory, observation, and instrumentation.
Its activities span the entire spectrum of contemporary astrophysics: from the Solar System to distant galaxies, including extreme phenomena, fundamental physics, and the metrology of time and space.
In particular, the Observatory produces the French legal time and the ephemerides of Solar System bodies, and develops instruments for major ground-based and space-based facilities. It is a founding member of PSL University.
The year 2026 marks a double anniversary: the 150th anniversary of the founding of the Observatory in Meudon, established in 1876 at the initiative of Jules Janssen (1824–1907), and the 100th anniversary of its affiliation with the Paris Observatory, formalized in 1926.