The solar system was formed approximately 4.56 billion years ago. Despite the numerous theories that have been developed over the years, the formation and evolution of the solar system still remain unclear.

A team of Leiden astronomers has managed to calculate the first 100 million years of the history of the Oort cloud in its entirety. Until now, only parts of the history had been studied separately. The cloud, with roughly 100 billion comet-like objects, forms an enormous shell at the edge of our solar…

This thesis is largely an experimental study on the formation of solid-state simple and complex organic molecules in the H2O-rich and CO-rich ice phases of dense interstellar clouds and dark cores.

Supervisor: S.F. Portegies Zwart Co-Supervisor: A.G.A. Brown

This thesis concerns the relation bettween the good reduction of Shimura varieties and the associated loop groups.

Promotores: S.J. Edixhoven, F. Andreatta

Stars like the sun are born in large molecular clouds existing from gas and dust. During the formation process, the chemical composition of the material can be altered drastically by the changing physical conditions.

Large areas of space are filled by molecular clouds that consist of gas and dust grains that are the remnants of dead stars. When these clouds start collapsing, the decreasing temperature and increasing density cause gas particles to start accreting onto dust grain surfaces.

An international team led by Leiden astronomers has discovered diverse ices in the darkest, coldest regions of a molecular cloud. To do so, they used the James Webb Space Telescope. This discovery allows astronomers to examine the simple icy molecules that will be incorporated into future exoplanets,…

PhD defence

He discovered how to determine the rotation and centre of our Milky Way, predicted where comets come from and laid the groundwork for radio astronomy: Leiden Professor of Astronomy Jan Hendrik Oort (1900 – 1992). Piet van der Kruit, whose PhD supervisor was Oort himself, has written a biography about…

This thesis takes steps toward understanding the interaction between gas-phase and solid-state molecules in star- and planet-forming regions.

From the Big Bang to superconductivity. Many ground-breaking discoveries have been made in Leiden University’s long history.

The cloud is of increasing importance in our daily lives. It is thus crucial that they work properly and are reliable. Alex Uta, assistant professor at LIACS, received a Veni grant to investigate the reproducibility of experiments in the cloud.

The success of Dutch radio astronomy in the last century was largely due to Leiden astronomer Jan Hendrik Oort. He made astute use of circumstances in the post-war period. Historian Astrid Elbers' research focuses on this golden period.

The Old Observatory has a rich history. On this page you will find a short version of the history that took place in the observatory.

The quantum computer is on its way, but is society ready for it? Quantum computers have a reputation of being difficult to grasp because of their complexity. This limits society’s ability to envision future applications creating a gap between society and quantum computers. A consortium of 14 knowledge…

In September 2021, ACPA PhD Candidate Gabriel Paiuk will premiere a new work titled Sound Theory (The Clouds) as part of the 2021 Gaudeamus Muziekweek Festival. The performance will take place on September 10th, 20:30 at the De Helling (Utrecht, NL).

Promotores: F.H. van Lunteren, F.P. Israel

If there is life outside our galaxy, how could we find it? In his Oort Lecture, James Kasting talks about his search for simple life on other planets. Kasting was in the Netherlands for two weeks, because he was invited as the Oort Professor 2018.

The project has been done in the Quantum Matter & Optics group under the supervision of Prof.dr.ir. Tjerk Oosterkamp.The title of the presentation is:

Het project heeft plaats gevonden onder begeleiding van Prof.dr.ir.Tjerk Oosterkamp. De titel van de presentatie is:

The project has been done in the Quantum Matter and Optics group under the supervision of Prof.dr.ir. T.H. Oosterkamp and Dr.ir. S.J. van der Molen . The title of the presentation is: ''Friction of ice skating.

The project has been done under the supervision of Dr. Diego Garlaschelli and Dr. Frank Takes. The title of the presentation is: ''Complex Network Analysis of Darknet Black Market Forum Structure.

The project has been done in the Quantum Matter Optics group under the supervision of Dr.ir. Sense Jan van der Molen. The title of the presentation is: ''A Technique for Studying Surface Profiles of Two-Dimensional Materials in LEEM.

The project has been done in the Cosine group under the supervision of Prof. Dr. Martin van Exter and MSc Marta Brusasca.The title of the presentation is: ''Calibration of the condifood DemoDevice.

Professor Ewine van Dishoeck, together with an international team of colleagues, has written an overview of everything we know about water in interstellar clouds thanks to the Herschel space observatory. The article, published in the journal Astronomy & Astrophysics, summarizes existing knowledge and…

The winner of the highest scientific distinction in mathematics, an explanation for wine tears and much more mathematical theory and application. From 8 to 12 July, 550 mathematicians will meet in the center of Leiden to discuss differential equations.

The first Leiden Science Family Day on Saturday 6 October was a great success. During the ‘Weekend of Science’ more than 700 visitors, including 350 children, visited the Faculty of Science. With a program full of experiments, lectures, guided tours and demonstrations, visitors were given a glimpse…

Alumni event

Whether finding signals of dark matter or discovering hydrogen in the vicinity of exoplanets, Leiden astronomers are world players in their field, and they are part of a long tradition: Leiden was the first university in the world to have its own observatory.

From children’s inability to identify animals to a big protest at the opening of the academic year: below are some of our most popular articles of 2019.

Alumni event

The yearly Oortlezing, in the memory of the famous Dutch astronomer, is organized by the Stichting Het Jan Hendrik Oort Fonds and Leiden Observatory. This public lecture is always about a current astronomical topic and is meant for a broad audience that is interested in astronomy. The public lecture…

We strive to address the challenge of constructing a modeling language to write software which can take advantage of recent hardware developments (multicore, cloud) without compromising in its abstraction levels.

The origin and evolution of galaxies are closely tied to the cyclic feedback processes between stars and the interstellar medium (ISM).

General

Leiden Observatory provides a dynamic, international environment for work and study. Established in 1633, the institute has a very rich tradition. The famous Old Leiden Observatory is the oldest operating university observatory in the world. At Leiden Observatory we carry out world class research and…

The colloquia Ehrenfestii take place about once every month. This lecture series has been running since 1912.

In design optimization problems, engineers typically handcraft design representations based on personal expertise, which leaves a fingerprint of the user experience in the optimization data. Thus, learning this notion of experience as transferrable design features has potential to improve the performance…

Arts and culture, Concert

Promotor: J. Schaye

We simulate interstellar clouds with special plasma expansions and chemical reactions on icy dust grains to be measured in ultra-high vacuum setups. This provides the data necessary to guide and interpret astronomical observations and to model reaction networks in space. [Harold Linnartz]

Promotores: Prof.dr. S.J. Edixhoven, Prof.dr. E. Ullmo (University Paris-Sud)

PhD defence