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

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.

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.

An international team of astronomers that includes researchers from Leiden has discovered the most distant galaxy yet. The galaxy, called EGS8p7, is 13.23 billion light years away from Earth and already existed when the universe was only 550 million years old.

Leiden PhD researcher Karin Öberg is one of the 17 winners of the NASA Hubble Fellowship. When she has obtained her PhD this autumn she will move to the United States for three years to conduct post-doctoral research into the role of ice in star formation.

Large telescopes can look so deep into the Universe that they can also look back billions of years in time. From 2018, the successor of the Hubble Space Telescope, the James Webb Space Telescope, will be able to see the period just after the Big Bang, when the first stars and galaxies formed. Astronomers…

Promotor: Prof.dr. M. Franx, Co-Promotor: Rychard Bouwens

Twee teams of astronomers, including from the universities of Amsterdam and Leiden, have discovered how hot gas giants are surrounded by large halos of thin helium gas, an indication that they are slowly losing their atmosphere. The helium, that was recently seen for the first time by the Hubble space…

A permanent exhibition on the place of humans in the cosmos. This is something Franx wants to use his Spinoza Prize for. ‘So much progress has been made that we are still trying to define the questions. In finding the answers we are constantly coming up against surprises.’

Astronomy PhD candidate Emiel Por has been selected by NASA as one of the 24 Hubble fellows in 2020. He will be conducting research at the American Space Telescope Science Institute in the fall within the programme 'Are we alone?'.

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.

Promotores: Prof.dr. M. Franx & Prof.dr. P.G. van Dokkum (Yale University)

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

Exactly a century ago, astronomers observed the first two diffuse interstellar bands (DIBs) in space. A DIB manifests itself as a colour of light that is missing in the radiation from stars behind an interstellar cloud. Although about 500 DIBs are yet discovered, they remained inexplicable until recently.…

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.

Emiel Por is our Leiden Observatory's nominee for the C.J. Kok Jury Award 2020.

Former PhD student Cameron Mackie will been awarded not one, but two dissertation prizes for his thesis on the aromatic universe. His work could provide us with a virtual sniff of space. ‘These molecules in space likely smell like a big charcoal grill!’

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.

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

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.

How can you see something that’s invisible? Well, with Euclid! This future ESA telescope will map the structure of the Universe and teach us more about invisible dark matter and dark energy. Scientific coordinator of Euclid and Leiden astronomer Henk Hoekstra explains how this works.

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…

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.

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

How big is the universe? How do stars form and evolve? And does life exist elsewhere in the Universe? These main questions in astronomy are the themes of the new exhibition Above & Beyond, which was created in honour of the hundredth anniversary of the International Astronomical Union (IAU). The exhibition…

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).

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.

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

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.

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

This thesis describes the Multi-site All-Sky CAmeRA (MASCARA), which consists of two small robotic telescope designed to detect exoplanets around the brightest stars in the sky.

Rychard Bouwens from the Leiden Observatory is the first scientist in the Netherlands to be assigned a Large Programme on the state-of-the-art ALMA telescope in Chile. With his team, he wants to use the unique capabilities of the billion-euro facility to investigate the build-up of massive galaxies…

Bernhard Brandl, the new Leiden Professor of Infrared Astronomy, is developing instruments for the world’s largest telescopes. These telescopes can be used to observe objects in space that are more than 13 billion years old. Brandl will deliver his inaugural lecture on 26 September.

Astronomers led by Pieter van Dokkum have discovered a galaxy that barely contains any dark matter, which actually proves that dark matter does indeed exist. The research results will be published this week in Nature.

Astronomers at ASTRON and Leiden University have used the LOFAR radio telescope to discover a 'brown dwarf' – a faint object more massive than Jupiter, but significantly less massive than the Sun. The discovery of the object dubbed Elegast, opens up a new path that uses radio telescopes to discover…

Astrophysicist Ewine van Dishoeck has been awarded an honorary doctorate from the University of Geneva. She received the award on 11 October during the Dies academicus of the Swiss university, which, like Leiden University, is part of the European research university federation LERU.

Astronomer Ignas Snellen studies exoplanets using telescope observations. But how is that possible when all the big telescopes are more or less at a standstill? Luckily, he has contact from home with a robot telescope in Mexico and his WIFI is finally working well.

When stars are born, large clouds of gas and dust form that are known as circumstellar discs. Research by PhD candidate Francisca Concha-Ramírez shows that strong radiation from neighbouring stars soon evaporates the dust in these discs, which can prevent planet formation at an early stage. PhD defence…