‘What if we switch off all the lights one evening? That idea crossed my mind from time to time. And when I mentioned it to a taxi driver one day, he said: “Oh, you mean: lights out, stars on!” That’s not completely true, of course, because the stars are always on, but his phrase summed up the idea n…

Fish populations in lakes and rivers have declined in recent decades. This is probably due to light and noise pollution. The Horizon Europe grant enables ecologist Hans Slabbekoorn to investigate this and improve the situation for migrating fish. In order to do so, a seven-metre-long swimming tunnel…

Nausea, neurologic pain and hair loss: some of the severe side effects of chemotherapy. Not necessary, biochemist Liyan Zhang showed. Together with Leiden biologists and others, she achieved great results with a drug that is only active in combination with light. Zhang will defend her PhD on 4 July.

Petr Steindl works on quantum dots in microcavities for his PhD research. He manipulates single-photons to create complex structures of light. Applications could include quantum communication and gates for quantum computers.

A suitcase covered with stickers from various universities, containing a quantum light source. Since April 2024, this suitcase has been visiting scientists in Europe researching single photons: the smallest possible quantity of light. The suitcase, also called ‘Q-torch’, travels from lab to lab like…

New archaeological research into grave goods and skeletal material from the oldest grave field in the Netherlands shows that male-female roles 7,000 words ago were less traditional than was thought. The research was conducted by a multidisciplinary team of researchers led by Archol, the National Museum…

In 2011, the Udhruh Archaeological Project was launched, bringing together teams of Jordanian and Dutch archaeologists to investigate the region and reconstruct ancient water harvesting techniques in the extremely arid landscape of Udhruh. Access to fresh water remains one of the most pressing global…

Hoping to learn something about the human brain, Leiden researchers are creating a setup to shoot single photons, particles of light, into someone’s eye. ‘The eye is a passageway to the brain.’

Writing with Light Magazine. Issue no.1 is now available for download as a open access pdf/interactive edition or purchase as limited-run print edition. The magazine builds on our prior work with the journals Cultural Anthropology and Visual Anthropology Review and the editorial collective consists…

Packages of DNA strands containing silver, measuring just two or three nanometres in size. Leiden physicists Donny de Bruin and Dirk Bouwmeester create these packages, which can enter living cells on their own. They then activate the silver with light, causing the cells to break down. This could, in…

Ecologist Sebastiaan Grosscurt became a successful wildlife journalist after graduating. But he decided to focus on science instead. He started his PhD research this year on the cumulative effect of light and noise pollution on animal behaviour.

On 25 September, lights throughout Leiden will be turned off for the Seeing Stars event. What makes the urban night so special? We asked university lecturer Sara Brandellero, who researches cities, night and migration.

For the first time, an international group of astronomers have seen the heat glow of two ice giant planets colliding. They could also observe the resultant dust cloud move in front of the parent star several years later. Led by Leiden astronomer Matthew Kenworthy, they monitored the star's brightness…

Archaeologist Bjørn Peare Barthold suspected farmers in a doctorless 19th century Dutch village may have been self-medicating to manage pain and disease. By examining the skeletons' dental calculus this hypothesis could be tested. Science Magazine interviewed him about this new technique.

'Education has always been something I am very interested in,' says the passionate Michiel Hogerheijde. He was already chairman of the astronomy programme committee and has been teaching for many years. Since 1 October, he is also the new Programme Director of the astronomy bachelor. 'I really enjoy…

December 2020 saw the crowning publication of the Landscapes of Survival project by Professor Peter Akkermans. Its main topic is human habitation in marginal environments like the deserts of the Arabian Peninsula. ‘The people living here built their own society, and they would not have viewed it as…

After many years of preparations, CERN has approved a groundbreaking new experiment: the Search for Hidden Particles (SHiP). Physicist Alexey Boyarsky was involved from the start. ‘We know there is physics that’s missing and we aim to find it.’

Leiden physicists Alexandre Morin and Samadarshi Maity study self-organisation and flocking phenomena. They shed light on flocking, which helps to understand how it is possible that birds in a flock don't collide. With plastic microbeads, they create an experimental setup and they developed a mathematical…

Over the past few months, Urban Studies students have been helping to think about the realisation of the Humanities Campus. To test their knowledge in practice, the future urban specialists gave advice on several different aspects, including thermal energy storage and the new central campus building…

Piercing through the skull with an ice pick, administering electric shocks without an anaesthetic, or applying leeches to the uterus: these may seem like medieval methods of torture, but they are in fact therapies used in medicine. Willem van der Does writes about all of them in his new book. ‘Physicians…

PhD student and research journalist Sebastiaan Grosscurt won a Tegel in May. In the data category, Grosscurt and his colleagues won the prestigious Dutch journalism award. 'For me, ecological research and journalism are two ways of achieving the same thing.'

After months of preparation, the moment of truth had arrived: would the skies above Leiden clear for the promised glitzy planet-and-star show? The people of Leiden turned out in their hundreds to go star-hunting on 25 September. They became more aware than ever of the effects of light pollution.

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Since 24 March, the Kamerlingh Onnes Building of the Faculty of Law has been full of hundreds of colourful jellyfish. When the light falls in through the skylight, passing students imagine themselves in a magical underwater landscape for a moment. But behind that enchanting sight is a serious message:…

Symposium

Turkish politics was shaken by the arrest of Istanbul mayor Ekrem İmamoğlu, along with dozens of others from the main opposition party.

This FLO event is focusing on the overlap between all 4 programs (Psychology, Educational sciences, Political Sciences end Cultural anthropology) and aims to shed more light on what defines and unites us as Social Scientists. Where is the overlap in what we do, wo who are and what we strive for? The…

What will happen if the lights in a large part of the city are switched off? How many stars can you see without all that light pollution? This is what researchers, artists and the residents of Leiden are going to investigate during Seeing Stars Leiden on 25 September. ‘Leiden is the ideal place for…

While investigating 16 years of images of young stars from a retired astronomical camera, Leiden master's student Sam de Regt discovered that two of those stars were still enveloped in birth clouds. Never before has anyone captured these two stars in so much detail. He publishes his data-cleaning method…

A suitcase as a messenger of quantum science. That is the idea behind QuanTour, a project connecting researchers from 12 European universities. In December, the suitcase landed in Leiden. A month later, it is time to pass the baton to Copenhagen. But what happened to it in Leiden?

James Webb life’s building blocks

Smart drug carriers, uneven cosmic expansion, and solar energy storage in molecules. These are the topics of three newly awarded NWO-XS grants to researchers at the Faculty of Science.

It was not light, but its absence that caught Stephanie Noach's attention a few years ago. With her research on darkness in art, she aims to show how darkness can question and sometimes even undermine colonial imagery.

Leiden artist Jos Agasi gets to create the artwork for the atrium of the new Gorlaeus Building. His work was chosen from several entries and will be a real eye-catcher in the building. The artist has a fascination for light and uses it to create works of art with all kinds of materials, objects and…

Researchers using NASA’s James Webb Space Telescope may have detected atmospheric gases surrounding 55 Cancri e, a hot rocky exoplanet 41 light-years from Earth. This is the best evidence to date for the existence of any rocky planet atmosphere outside our solar system.

For over a year now, the James Webb Telescope has been sending stunning images that exceed astronomers’ expectations. The photos are fascinating to see, but what exactly are we looking at? Assistant professor Melissa McClure explains.