You can make some astounding images using just a box with a hole. Inspired by the celebration of Leiden as the European City of Science, Professor Matthew Kenworthy left several pinhole cameras across the Observatory over the course of 2021. This is how the simplest devices may uncover the greatest…

To understand the universe as a whole, simulations on a cosmic scale are required. An international team of astrophysicists, led by Leiden University, is today making one of the largest cosmological datasets ever available for free. It comprises more than 2.5 petabytes of simulation data.

ASTRON en de Universiteit Leiden beginnen samen een nieuwe leerstoel over sterrenkunde en AI. Bijzonder hoogleraar Joeri van Leeuwen gaat deze positie vullen.

They are among the rarest and most extremely luminous stars in our universe: yellow hypergiants. Their spectacular eruptions have intrigued astronomers for decades, and now an international team led by Leiden’s emeritus professor Arnout van Genderen has gained new insights into the mechanisms behind…

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.

Not everything that comes close to a black hole is swallowed by it. Black holes can also hurl material away, and that chance turns out to be considerably bigger than previously thought. Martijn Oei's accidental discovery and his subsequent research on it earned him a cum laude promotion on 12 Decemb…

Astronomer Joseph Callingham and his team have observed for the first time a clear signal from a giant burst from a star outside our solar system. This would have a devastating impact on any unfortunate planet orbiting the star.

The British astronomer and mathematician Edmond Halley was not, after all, the first to understand the cycle of the comet that now bears his name. This is shown by research conducted by, among others, Professor Simon Portegies Zwart. It was the monk Eilmer of Malmesbury who, as early as the 11th century,…

Elena Maria Rossi is fascinated by black holes. Her appointment as a professor was a long-held wish, partly because there are so few female professors in her field. ‘My appointment is also a milestone for the Leiden Observatory.’

How do atoms and molecules end up forming planets? That's what astrochemist Julia Santos studied during her PhD. She discovered the dominant process behind the formation of methanol in space – a finding that surprised the entire field.

Astronomers led by Leiden PhD candidate Richelle van Capelleveen have, for the first time, discovered an exoplanet that has carved a bright gap in the protoplanetary disc around its star. This rare observation provides new insights into how young planets shape their surroundings.

Astronomers led by Simon Portegies Zwart used simulations to reconstruct how three stars were ejected from the star cluster R136, 60,000 years ago. The analysis reveals that five stars were involved in the event in the Tarantula Nebula.

‘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…

How do you detect life on a planet light years away? During her PhD research, astronomer Willeke Mulder worked on an instrument to detect such signals – culminating in an experiment from a hot air balloon.

Leiden scientists lead COLIBRE, a groundbreaking set of cosmological simulations. By including key missing physics, cold gas and cosmic dust, they offer the most realistic picture yet of how galaxies formed and evolved since the dawn of time.

The first full-colour images of the cosmos from ESA's space telescope Euclid were presented today. Never before has a telescope been able to take such crystal-clear astronomical images of such a large part of the sky and so far into the deep universe. The five images illustrate Euclid's full potential;…

The supermassive black hole at the center of the Circinus galaxy is being fed with gas by two spiral arms. This is what PhD candidate Wout Goesaert discovered. But only a small percentage disappears into the black hole, the rest is ejected.

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…

Space telescope Euclid is capable of unravelling the secrets of the universe. That is what the images published by ESA today show, according to astronomers working with the telescope's data. The images exceed all expectations. Scientists within the Euclid consortium, including astronomers Henk Hoekstra…

Galaxies in the early universe contain more dust and hidden star formation than previously thought. That's what Ivana van Leeuwen concludes in her PhD research, where she combines data from various telescopes to create a more complete picture.

Research into depression in children, Leiden alumni in the Dutch House of Representatives and an exceptional achievement by one of our students: what do this topics have in common? They are among our most read stories of 2021.

The 'deepest and sharpest' image of the Universe to date: the first photos from the new James Webb space telescope yesterday mesmerised astronomers and the public alike. Leiden Professor of Molecular Astrophysics, Ewine van Dishoeck, spoke to various media outlets about the first images, which include…

Henk Hoekstra and Alessandra Silvestri work on the astronomy and theoretical physics in the Euclid mission. These Dutch researchers are part of the mission.

How do molecules originate and evolve in space? And how does that ultimately determine the chemical composition of planets and their atmospheres? The Dutch Astrochemistry Network (DANIII) receives 1.6 million euros from NWO to find out. A large group of Leiden astronomers and chemists is contributing:…