Universiteit Leiden

nl en

Leiden Observatory

About us

Leiden Observatory is the astronomical institute of the Faculty of Science of Leiden University.

It is established in 1633, and is the oldest university observatory in operation today, with a very rich tradition. Leiden Observatory carries out world class research in the formation of structures in the universe and the origin and evolution of galaxies, the detection and characterization of exoplanets, and the formation of stars and planetary systems. The institute consists of about 35 faculty and adjunct faculty, 50 postdoctoral researchers, 50 MSc and 80 PhD students, and 30 support staff. We offer an excellent educational programme at the Bachelor’s and Master’s levels and a renowned PhD programme. Within the Faculty of Science, the institute closely collaborates with the Leiden Institute of Physics, the Mathematical Institute and the Leiden Institute of Advanced Computer Science.

World class

Our ambitious research programme focuses on observations using the world’s most powerful ground-based and space telescopes, on theoretical astrophysical and astrochemical modeling, on large scale simulations, and on laboratory experiments that mimic space conditions. Our world-class astronomical research is supported by the development of key technologies for ground-breaking astronomical discoveries and translates into an excellent educational programme at the Bachelor’s and Master’s levels. Our PhD programme delivers scientists that that find employment in astronomy, industry and society worldwide. Through our work, we also seek to engage the public with the wonders of the universe and share the scientific, technological, cultural and educational aspects of astronomy with society.


Physics of the Universe

Research at Leiden Observatory is organised in two broad themes: Galaxies and the structures in which they are embedded [LINK to 6] and Exoplanets and the formation of stars and planets [LINK to 7]. Our research covers the fundamental physics of the origin and evolution of the large scale structures and galaxies in the universe as well as the origin of stars and their planetary systems. Questions we study include: what is the true nature of dark matter and dark energy, and is Earth the only habitable planet in our universe?



The founding of Leiden Observatory goes back to 1633 when an observing platform was constructed on the Academy Building to house Snell’s quadrant. This makes Leiden Observatory the oldest university astronomy department in operation today. In 1860 a state-of-the-art observatory building was constructed on the recently decomissioned ramparts of the city of Leiden. Here, astronomical research blossomed. In the early twentieth century, major progress in physics was taking place in Leiden with the work of Lorentz, Kamerlingh Onnes, Zeeman, Ehrenfest and Einstein. In these same years, Leiden Observatory was led by famous astronomers like de Sitter, Herzsprung, and Oort. Major discoveries of this period include the Einstein-de Sitter solution to General Relativity, the Herzspung-Russell Diagram, the rotation of the Milky Way by Oort, and the prediction of the 21-cm Hydrogen line by van de Hulst. In 1928 the third General Assembly of the International Astronical Union was held in Leiden, and in 1962 the European Southern Observatory convention was signed at the same Academy Building where Leiden Observatory originated. Four Leiden professors (Blaauw, Woltjer, van der Laan, and de Zeeuw) served as Director General of ESO. In 1974 Leiden Observatory moved to the Huygens Laboratory located in the Leiden Bio Science Park. Today, Leiden Observatory is housed in the Huygens Laboratory and the adjacent Oort building. [Read more on the history of Leiden Observatory]


Leiden Observatory offers students a three-year BSc programme and various two-year MSc programmes. The programmes are closely linked to our research programme and students can benefit from our scientific strengths. [Read more].



Leiden Observatory’s accomplishments in astronomy and astrophysics are reflected in a wide range of awards and prizes received by its faculty members, research staff and students. In recent years this included the Albert Einstein World Award of Science for Ewine van Dishoeck; the Academische Jaarprijs 2012 for the iSPEX project; several Spinoza prizes and Royal Academy of Sciences professorships; Advanced grants from the European Research Council; and international postdoctoral prize fellowships such as Hubble fellowships and EU Marie Curie fellowships.