The Old Observatory houses four historical telescopes. On this page you can learn more about them.

Our current research focusses on the exploration of the Universe using the neutrino. This neutral, almost massless and only weakly interacting particle can open a window to the distant Universe and also dense regions from which photons cannot escape.

A new way to decipher the light from distant worlds could give us unmistakable evidence of extraterrestrial photosynthesis, and maybe alien plants, finds astronomy author Colin Stuart in the New Scientist. In his article, he describes the work of the group led by Leiden astronomer Rob van Holstein.…

Leiden scientists will be working on the development of a camera for the European Extremely Large Telescope that is currently under construction. On 28 September the Netherlands Research School for Astronomy signed an agreement with the European Southern Observatory.

After nearly 70 years, the Leiden Observatory has a new telescope. A crowdfunding action in March brought in the 20,000 euros required to build a solar telescope. On 19 September Rector Magnificus Carel Stolker officiated at the opening.

An international team of astronomers including Leiden scientists publishes the image of a young star with a surrounding dust disk that is still being fed from its surroundings. The phenomenon around the star SU Aur may explain why so many exoplanets are not neatly aligned with their star. The European…

An international team of astronomers from Leiden Observatory and others, has for the first time mapped a piece of the dark, cosmic web. The research strengthens the hypothesis that the young universe consisted of huge numbers of small groups of newly formed stars. The astronomers publish their findings…

Director General of ESO, Tim de Zeeuw received President of the Republic of Chile, Michelle Bachelet Jeria for a ceremony marking the first stone of ESO’s Extremely Large Telescope (ELT).

An international team led by Leiden astronomers has, after years of searching and defying the boundaries of a telescope, for the first time directly captured polarised light from an exoplanet. From this light they can deduct that a disk of dust and gas orbits the exoplanet. In this disk moons are possibly…

Promotor: J.N. Kok, Co-promotor: M.S. Lew

An international team led by Leiden astronomers has taken the first-ever image of a young, Sun-like star accompanied by two giant exoplanets. The researchers used The European Southern Observatory’s Very Large Telescope for this, known as ESO’s VLT. Images of systems with multiple exoplanets are extremely…

In 2015, Jorryt Matthee thought he discovered an extremely distant galaxy called CR7, which lacked elements heavier than helium. Three years later, he shows with measurements using the ALMA telescope that the galaxy does have carbon after all, and even in normal concentrations. The American Astronomical…

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.

Promotores: Prof.dr. M. Franx, Prof.dr. M. Kriek (Univ. of California at Berkeley)

Deep observations made with the MUSE spectrograph on ESO’s Very Large Telescope have uncovered vast cosmic reservoirs of atomic hydrogen surrounding distant galaxies. The exquisite sensitivity of MUSE allowed for direct observations of dim clouds of hydrogen glowing with Lyman-alpha emission in the…

The formation and evolution of galaxies is fundamentally driven by the formation of new stars out of cold gas.

New results from the Kilo-Degree Survey (KiDS) show that the Universe is almost 10 percent more homogeneous than previously thought. The new KiDS map was created using the partly Dutch OmegaCAM on ESO's VLT Survey Telescope on Cerro Paranal in Northern Chile. An international team of astronomers from,…

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.

Astronomer Jos de Boer has received the Chesneau Prize in Nice for his research into so-called protoplanetary disks. The prize is awarded to the best astronomical dissertation in the field of high angular resolution. 'I consider it a good opportunity to talk about my research.'

This thesis investigates how galaxies form and what diversifies the evolutionary histories of galaxies.

Promotores: F.H.J. Redig, W.T.F. den Hollander

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.

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…

Promotor: S.M. Verduyn Lunel

On Friday evening 17 September, Leiden astronomer Joe Callingham can be seen in a new series on Discovery channel. Killers of the Cosmos is about different deadly dangers lurking in the depths of space. Asteroids, cosmic debris, electromagnetic weapons… The show takes a film-noir approach to these threats,…

Astronomers from, among others, SRON and Leiden Observatory have discovered long-sought intergalactic gas with ESA’s space telescope XMM-Newton. This gas is one of the pieces of the puzzle to map the total amount of ‘normal’ matter in the universe. The research will be published in Nature on 21 June…

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.

With each discovery that is made, the universe reveals a fraction of its secrets: the most distant galaxies and quasars, the atmosphere of exoplanets, evidence of dark matter, complex molecules in space. This is what fills the days and nights of the researchers from the Leiden Observatory and their…

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

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…

The Netherlands Organisation for Scientific Research NWO allocates nearly € 19.5 million to a Dutch cluster that contributes to the development of an X-ray camera and spectrograph for the new European space telescope Athena. Leiden Observatory is one of the members of the cluster.

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.

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

For thousands of years bloodlines have been held as virtually unassailable credentials for leadership, with supreme political power perceived as a family affair across the globe and throughout history. At the heart of royal dynasties, kings were inflated to superhuman proportions, yet their status came…

How do stars and galaxies form? What is dark matter? To answer these and other questions, we need increasingly large telescopes. And to build these, we need international partnerships. A series on the impact of collaboration.

KM3NeT is selected as one of the ten top research facilities in NWO’s National Roadmap for Large-scale Research Infrastructure. Leiden physicist Dorothea Samtleben is the deputy program leader of Nikhef’s KM3NeT group.

Everyone wherever they are in the world can follow free online academic courses offered by Leiden University.

Promotor: W.Th.F. den Hollander Co-Promotor: F.M. Spieksma

By effectively integrating word-class scientific research and excellent education, you will become a professional astronomer with an internationally recognized degree.

By effectively integrating word-class scientific research and excellent education, you will become a professional astronomer with an internationally recognized degree.

By effectively integrating word-class scientific research and excellent education, you will become a professional astronomer with an internationally recognized degree.

By effectively integrating word-class scientific research and excellent business education, you will become a professional astronomer with an internationally recognized MSc degree prepared for technological business challenges.

By integrating world-class scientific research and education, you will become a professional physicist with an internationally recognized degree.