The Leiden Ranking – Open Edition is completely transparent. The ranking compiled by the CWTS uses open data and publishes the algorithms that are used.

Are magnetic fields older than the first light? And how did they influence the development of our universe right after the Big Bang? Cosmologists from Leiden, Groningen, and Utrecht are now collaborating to investigate this.

How should we address our colonial heritage? And how digital and accessible are our collections? Outgoing State Secretary Fleur Gräper spoke with researchers and heritage specialists about this on 25 January.

In a speech on Keti Koti the Dutch king, Willem-Alexander, apologised on behalf of the royal family for the Netherlands’ historical role in slavery. What is the significance of this?

What hidden nature is there in our cities and how can we use such organisms? This is what the HiddenBiodiversity project will be exploring over the next four years. The project’s kick-off meeting was held at the Hortus botanicus on Monday 26 September.

Joop Schaye, Professor of The formation of galaxies, has been elected as a member of the Royal Netherlands Academy of Arts and Sciences (KNAW). He will be officially inaugurated on 29 September.

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…

Four researchers from Leiden University have been awarded prestigious Vici grants the Dutch Research Council (NWO) has announced. The honoured applications are from researchers at the Faculty of Social and Behavioural Sciences, Leiden Observatory, the LUMC and the Faculty of Archaeology.

How do you combine the growth of wind energy with the protection of vulnerable seabirds? With her master’s thesis on this delicate balance, Sofie Hajer won the 2025 Unilever Research Prize. Her work provides new insights into how ecology and policy can strengthen each other.

The Dutch Research Council (NWO) has awarded Vidi grants to Leiden researchers.

Space for open dialogue on historical slavery was created at the Keti Koti Table at Museum De Lakenhal, organised by Leiden University and the Municipality of Leiden. There, just metres away from 17th-century paintings, Leideners shared a ritual meal and spoke about the effects of slavery and our colonial…

The Netherlands returned 478 artefacts to Indonesia and Sri Lanka this week, on the advice of a Dutch committee. Rightly so, says Leiden professor Pieter ter Keurs from the Museums, Collections and Society interdisciplinary research programme. ‘But do make it clear why you are returning something.’

An international team of researchers led by astronomers from Leiden University (the Netherlands) has produced the first sharp radio maps of the universe at low frequencies. Thanks to a new calibration technique, they bypassed the disturbances of the Earth's ionosphere. They used the new method to study…

It’s starting to become a real Dies Natalis tradition: on 8 February professors from Leiden University teach a class at primary schools in the region. This introduces children to academia and teaches them more about conducting research. ‘Had you expected me to be a woman?’

Did you get a taste for recording local wildlife with Expeditie Stadsnatuur? Join the higher education BioBlitz and help us discover what is growing, crawling and fluttering on our campuses.

No less than four Leiden research teams have been awarded a grant by NWO. On 27 July NWO honoured 21 applications in the Open Competition ENW-XL. NWO awards the grants to consortia in the exact and natural sciences who are doing unconnected fundamental research that is 'driven by curiosity'.

For the first time, we’re seeing what Euclid sees. The telescope’s initial observations have provided a wealth of new information about our universe. But according to cosmologist Alessandra Silvestri, this is just the beginning. The research helps us gain a deeper understanding of the past, present,…

How do galaxies form? That is what astronomer Mariska Kriek will be researching in the coming years. She received an NWO Vici grant of 1.5 million euros to study galaxies in the early universe. ‘This research uses new and unprecedented observations from the James Webb Space Telescope (JWST). These allow…

For the first time, astronomers have observed in three dimensions that gas from spiral galaxies is blown upwards and downwards at high speed, far out of the galaxy. They thereby confirm the theory of galaxy evolution: that star-forming galaxies create intergalactic gas flows by discharging gas along…

Five projects with researchers from Leiden University have received a grant from the Dutch Research Council (NWO) to build or upgrade existing research facilities.

As of 12 Januari 2026, the FSW faculty building is called Agora. This name was chosen by the FSW community. In ancient Greece, the agora was the heart of the city: a place for meeting, dialogue and the exchange of ideas. This is exactly how we see our faculty building: an open space where knowledge,…

PhD defence

Alumni event

She stands out for the moderate tone she takes in discussions on Dutch talk shows. Without judgement you can have an open conversation, criminal lawyer Natacha Harlequin learned in her student days in Leiden. ‘What I personally think of the alleged act doesn’t matter so much.’

No more lectures and exams for the Radio Astronomy course taught by Michiel Brentjens. The corona crisis is a moment of reflection that has changed his whole way of teaching. Instead of being in front of the class, he lets his students build a radio telescope with paint cans.

Learn how to use Maileon’s editor and how to follow the editorial guidelines.

Racism and discrimination come in many different shapes and forms – in the Netherlands too. Verbal attacks, stereotypes and violence: some people are confronted with these on a daily basis. A group that is often not included in research and the debate on racism is people of Asian descent. The Diversity…

Marlon Titre (1982) studied at Royal Conservatoire The Hague, did his PhD and studied at Leiden University, earned several other qualifications and is now, among others, Director of Filmhuis The Hague. Who is this multi-talent?

April is the month of showers and tulip fields but did you know that it is also Global Citizen Science Month? And the future of our Leiden citizen science community looks rosy, says coordinator Margaret Gold. She is happy to come and tell you all about this − and to exchange knowledge and ideas. ‘See…

Simulations of galaxy formation provide much more information about galaxies than a telescope. Simulations have been improving significantly in recent years. Astronomer Evgenii Chaikin made such a significant contribution to this field that he graduated with honours on February 27th.

Leiden researchers from different disciplines look together at complex social problems. What happens when they join forces with artists? The results could be seen on Tuesday 11 June during a unique exhibition. Take a look for yourself:

Infecting each other with viruses and bacteria while protecting yourself with medicines and vaccinations. Sounds like a fun evening, right? Master students Life Science & Technology Rafael Jezior and Dennis de Beeld certainly think so. Together, they developed ImmunoWars: an exciting card game based…

From research on stellar winds to sign language: an impressive seven researchers from Leiden University will receive a prestigious Vici grant from the Dutch Research Council (NWO).

It is a familiar phenomenon: you ask the assistant on your phone to call your mother, but it calls a friend instead. Tom Kouwenhoven, PhD student in the SAILS programme, investigates how humans and Artificial Intelligence (AI) can better communicate with each other, so that these kinds of situations…

Not only dark matter, but also ordinary matter and dark energy are tracked in the largest ever cosmological computer simulation ever. In the FLAMINGO simulations, you can see virtual galaxies and clusters of galaxies emerging over the course of billions of years. This is no easy task: with more than…

Pope Francis has appointed astronomer Ewine van Dishoeck to the Pontifical Academy of Sciences. She joins an illustrious list of Nobel Prize winners, such as Ernest Rutherford, Max Planck, Niels Bohr and Erwin Schrödinger. What is her view on this? An interview with our professor of Molecular astrop…

A true shower of awards for students from the Faculty of Science during the annual KHMW Young Talent Awards ceremony. On Monday, 25 November, no less than nine first-year students received a prize for the best academic results in their first year. In addition, there were graduation prizes for master’s…

More than 700 visitors got to know the Science Faculty during the Leiden Science Family Day. People of all ages could enjoy fascinating experiments, tours, interesting lectures, spectacular nitrogen shows and various workshops. It was an informative day with many (future) scientists, amazement and,…

Martina Huber, Jacqueline Labra Munoz research Alzheimer's disease. They study ferritine, iron storage in the brain. An inbalance of iron could play a role in this form of dementia.

Almost everywhere in the world where the post exists, the beadle is a ‘master of ceremonies’ who only makes his appearance on special occasions. In Leiden the beadle does much more. He is indispensable at dissertation defences and orations. He directs ceremonies and is a master at calming nerves.

Jasper Knoester is the dean of the Faculty of Science. How is he doing, what exactly does he do and what does his day look like? In each newsletter, Jasper gives an insight into his life.

Do you also love a city where nature can bloom, crawl and flutter freely and exuberantly? And do you fancy a challenge out in the fresh air? If so, grab your mobile and take part in the BioBlitz 'Higher Education is Flourishing' from 22 May.

Researchers need to work in specialized environments when they work with dangerous bacteria and viruses. These microbes spread easily, so only in labs with a high biosafety levels they can be studied. Unfortunately, to look at the microbes properly, expensive microscopes are needed that are not always…

Confetti, stilt walkers and the new Einstein Fountain. On Monday, 2 September, the Gorlaeus Building of the Faculty of Science was festively opened. Together with Constantijn van Oranje, our students cut the ribbon. Dean Jasper Knoester: ‘The building is ready, now it is up to our students and researchers…

Due to its success, the Leiden2022 Q&A has been extended and is looking for even more thought-provoking, interesting or unusual questions.

Astronomers have used data from the European Gaia Space Telescope to discover 55 high-speed stars launched from the young star cluster R136 in the Large Magellanic Cloud, a satellite galaxy of the Milky Way. This increases tenfold the number of known “runaway stars” in this region. The team of astronomers,…

Workshops, tours, talks, music, an AI photobooth, interviews, a special poem and the launch of the LUF Children’s Fund. Alumni celebrated their alma mater’s 450th birthday in style on Saturday at the massively oversubscribed Dies Natalis Festival.

Jasper Knoester is the dean of the Faculty of Science. How is he doing, what exactly does he do and what does his day look like? In each newsletter, Jasper gives an insight into his life.

A single tiny molecule that can destroy flu, corona, HIV and Zika viruses? Yes, it really does exist. Biophysicist Niek van Hilten, who will receive his doctorate on 14 September, contributed to this discovery.