The design for the METIS instrument for the Extremely Large Telescope (ELT) is final. The European Southern Observatory (ESO) has given the green light for production of all parts of the instrument. It is the first ELT instrument, designed and to be built under Dutch leadership, to formally pass the…

The development of space resource activities is happening now. In the absence of a clear framework to govern these activities, there is a need to examine the concepts that are being discussed in order to ensure that they meet existing treaty obligations regarding on-orbit operations and space resource…

Promotor: S.M. Verduyn Lunel, Co-promotor: O.W. van Gaans

Are you thinking about studying Air and Space Law ? Learn more and watch the videos.

After 25 years, this December will finally see the launch of the long-awaited James Webb space telescope (JWST). Leiden astronomers are watching with great excitement: not only were they involved in the construction of important instruments on board, but the telescope will also reveal many new secrets…

Within the Vision on Teaching and Learning, one of the 8 ambitions is Activating Teaching and Learning. With the support of the Vice-Deans and Vice-Rector, Hester Bijl, the Saltswat project is working on accelerating this ambition. What is the purpose of this site? Being effective…

When a physical system possesses symmetries, these are often accompanied by a representation of the symmetry group on a Hilbert space. Group representations on Hilbert spaces have been extensively studied.

Leiden University is developing new short stay living space for foreign guests and employees. De Kloksteeg is currently the last of four projects that has been renovated by the Leiden University Real Estate directorate since 2017. The Service Centre International Staff (SCIS) is responsible for rental…

Bas Verberk defended his thesis on 6 September 2016

After a period of maintenance, the 'Photographer' telescope is available once again for visits at the Old Observatory.

After a period of maintenance, the 'Photographer' telescope is available once again for visits at the Old Observatory.

These podcast episodes were written for the Green Office’s Spring Podcast competition and miniseries 'Beyond the Safe Space', on the theme: the Planetary Boundaries, which took place between the months of March-May 2023.

Developing new medicines is one of modern science's most significant hurdles, a process marked by high costs, long timelines, and frequent failures of promising candidates.

This thesis examines silicon pore optics (SPO), a technology that exploits silicon wafers from the semiconductor industry to create extremely high quality X-ray optics, by studying its manufacturing process, applications, and prospects.

Meet the newest Full Professor at the Leiden Observatory: Joe Hennawi. All the way from Santa Barbara, California, Hennawi will strengthen the astronomy institute. In Leiden, he will use his recent ERC Advanced Grant to study how supermassive black holes come into existence.

Promotor: Prof.dr. T.H.W. Bäck

The sequence-dependence of biomolecular interactions involving nucleic acids and proteins is essential for numerous processes inside the cell. Insights into the underlying molecular mechanisms have been obtained using various biochemical and biophysical methods on two different levels — bulk and sin…

Astronomical observations of cold regions in the universe show a rich inventory of ices. Part of these ices may end up on planets like our own, but in that journey they will be exposed to considerable amounts of radiation.

Polycyclic aromatic hydrocarbons (PAHs) are the most abundant class of organic compounds in space. The PAH field evolves from the constant interaction between experimentalists, theorists, modellers and observers. While laboratory research and quantum chemical calculations together set up the molecular…

On 27 May, Dimitra Stefoudi defended the thesis 'Legal and policy aspects of space big data: legal implications of the use of large amounts of space data – regulatory solutions and policy recommendations'. The doctoral research was supervised by Steven Truxal and Bart Custers.

Earth and outer space have become increasingly intertwined environmentally, politically, and philosophically, as satellite constellations multiply, lunar activities expand, and aspirations for Mars and beyond gain momentum.

The strangest things come out at night. This is the motto of the Leiden Museum Night due to take place on 28 May. Leiden University is once again playing a key part.

Promotor: S.M. Verduyn Lunel, Co-promotores: M.F.E. de Jeu, B. de Pagter

The International Institute of Air and Space Law (IIASL) offers PhD candidates the possibility to enroll in the IIASL PhD Track.

In this thesis we study the moduli space of genus g curves, and the differential forms that occur naturally on this moduli space.

The Old Observatory in Leiden has reclaimed its most important telescope. Since the 1960s, the Meridian Circle (also known as a transit telescope) had been housed in the Boerhaave Museum. After more than sixty years, the telescope is finally back in its original location. Now, the public can enjoy it…

Since the disaster in Japan, professors, staff and students of the department of Japanese Language and Culture at Leiden University have regularly been contacted by the media asking for their opinion about the events taking place there. Ivo Smits and Kasia Cwiertka, Professors of Japanese, give their…

Of the 29 students who are still in Japan, the remaining four students in Tokyo have been advised to leave the area affected by the disaster.

This book focuses on transnationalism as a key concept to evaluate how Europe responds to cross-border security challenges.

The Standard Model (SM) of particle physics fails to explain several observed phenomena and is incomplete. In order to resolve this problem, one may extend the SM by adding new particles.

This volume investigates how urban growth and prosperity transformed the cities of the Roman Mediterranean in the last centuries BCE and the first centuries CE, integrating debates about Roman urban space with discourse on Roman urban history.

President Akio Yuki and his delegation were welcomed to Leiden by Vice-Rector Prof. Rietje van Dam-Mieras, Prof. Ivo Smits, Prof. Kasia Cwiertka and Dr Rogier Busser on Friday 13 May 2011.

On Monday 9 May Mercury will pass between the Earth and the Sun. This rare event can be followed in the Leiden Observatory. The Observatory's new solar telescope produces a very clear image and offers a unique opportunity to observe Mercury at the highest magnification possible in the Netherlands.

Port cities develop at the intersection of international trade and commerce and at the interface between sea and land. What does the future of port cities look like with urbanization, sea level rise, new migrant flows and the disappearance of old industries? This is addressed in the minor (Re)Imagining…

The Netherlands Ministry of Defense and Ministry of Security and Justice have requested the Centre for Terrorism and Counterterrorism to complete a research project on cyber governance from a policy perspective. The results of this project will contribute to the deliverables of the fourth International…

Nichiran kankei-shi o yomitoku [Revisiting the History of Dutch-Japanese Relations] is a new, two-volume Japanese publication with a chapter written by Wulan Remmelink. Both volumes offer a new look on the historical relations between Japan and The Netherlands during the Edo period by examining various…

The subject of this thesis, ‘Approach to Markov Operators on Spaces of Measures by Means of Equicontinuity’, combines an analytical and probabilistic approach to Markov operators.

Astronomers at Leiden University have discovered the first planets using a new instrument: the planet hunter MASCARA. This instrument, developed at Leiden Observatory, looks specifically for planet transitions around the brightest stars in the sky, which surprisingly enough have so far have hardly been…

This NWO-funded VICI project (2025-2030) led by Prof.dr. Petra M. Sijpesteijn examines the place-making processes in the early Islamic Empire.

Until the 1990s, the only known planets were those in our Solar System. Three decades later, several thousand exoplanets have been discovered orbiting stars other than the Sun, and substantial efforts have been made to explore these strange new worlds through spectroscopic analyses of their atmosphe…

Dividing Worlds: Tsunamis, Seawalls, and Ontological Politics in Northeast Japan

For the first time in over half a century, one of oldest telescopes at the Leiden Observatory is getting a major improvement.

Friday 25 April 2025 | Leiden University Institute of Security and Global Affairs – The Hague

The Leiden astronomer Huib van Langevelde) has been selected as the new director of the Event Horizon Telescope (EHT). The EHT is a collaboration involving about 350 scientists from 18 countries. It combines the ALMA array in Chile with sub-millimeter telescopes around the world and published the first…

For the first time more than half century, one of oldest telescopes at Leiden Observatory is getting a major improvement.

An unprecedented space telescope, an astrolab that makes space ice and molecules that may lead to the origin of life… The Ice Age project has all the prerequisites to become a very fascinating research project – if it is not one already. Leiden astronomers Melissa McClure, Harold Linnartz and Will Rocha…