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…

Rottgering

Media all around the world reported about it: the most detailed images yet seen of galaxies, shot by radio telescope LOFAR. The international team behind these amazing results were led by Leah Morabito at Durham University and included three talented Leiden astronomers.

This paper critically compares seven widely used risk assessment tools for violent extremism, including the VERA-2R, the ERG 22+, the SQAT, the IR46, the RRAP, the Radar, and the VAF.

Hot astrophysical plasma is ubiquitous in the Universe, from comets in our Solar system to the largest scale structures -- the cosmic web filaments. These hot plasmas, with the temperature of a few millions of degrees, are often observed in the X-ray wavelength range.

In this thesis, we present new laboratory data of interstellar dust analogues.

Over a seven year period an international team of scientists has mapped more than a quarter of the northern sky using the Low Frequency Array (LOFAR), a pan-European radio telescope. From Leiden, Astronomer Timothy Shimwell and Huub Röttgering, among others, are involved. It reveals an astonishingly…

When galaxies collide, do the black holes at their centre form a supersized black hole? This is what we think happens, but it's not as simple as that, according to Simon Portegies Zwart. Zwart, computer scientist and astronomer, has been awarded a VICI grant to research this phenomenon.

PhD Defence

A galaxy is already incredibly large, but it can get even bigger. Astronomer Reinout van Weeren investigates clusters of galaxies, one of the largest structures in the universe. For his research into the origins and evolution of these clusters, he obtained an ERC Starting Grant of 1.5 million euros.…

A team of Leiden astronomers used the latest set of data from ESA’s Gaia mission to look for high-velocity stars being kicked out of the Milky Way, but were surprised to find stars instead sprinting inwards – perhaps from another galaxy.

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.

An international team of astronomers, including Leiden's Maciej Bilicki, has discovered an enormous supercluster of galaxies. The supercluster had previously been overlooked because it was obscured by our own Milky Way. The researchers are publishing their findings in the Monthly Notices of the Royal…

In 2018, astronomer Jorryt Matthee won the C.J. Kok Jury Prize for the best dissertation of the Faculty of Science. He succeeded in finding a number of rare galaxies from the early Universe. One of them received the same initials as football player Cristiano Ronaldo: CR7.

Promotor: H.J.A. Rottgering, Co-Promotor: R.J. van Weeren

Dwarf satellite galaxies in the Milky Way perform different dances than researchers initially expected. Marius Cautun from Durham University received a Marie Curie grant to unravel the mysteries of this orbital dance. October 1st 2018 he will start his research at the Leiden Observatory.

A team of astronomers of Leiden University and the University of Texas (Austin, United States) has discovered a new way to map distant galaxies. They did so by observing the fingerprint of oxygen in a distant galaxy, something that is usually not possible from Earth. The researchers will publish their…

Promotor: K. Kuijken, Co-Promotor: H. Hoekstra

Promotor: K.H. Kuijken

By a stroke of luck, a team led by Dutch PhD student Martijn Oei has discovered a radio galaxy of at least 16 million lightyears long. The pair of plasma plumes is the largest structure made by a galaxy known thus far. The finding disproves some long-kept hypotheses about the growth of radio galaxie…

An international team of astronomers has published the most sensitive images of the Universe ever taken at low radio frequencies, using the International Low Frequency Array (LOFAR). ‘LOFAR is unique in its ability to make high-quality images of the sky at metre-wavelengths’, said Huub Röttgering, Leiden…

Two Leiden astronomers will receive the prestigious IAU PhD Prize. Both Jorryt Mathee and Niels Ligterink of the Leiden Observatory won a prize. Scientific director Huub Röttgering: We are proud that this year two of our PhD students receive an IAU prize for the best thesis in their field of researc…

This thesis presents pioneering work on the panchromatic emission of some of the most luminous galaxies in the early Universe: star forming galaxies and active galactic nuclei.

Astronomers want to understand the Universe, from the Big Bang to the present day, and what the future will hold. In Leiden they focus on two key questions: ‘How did stars and planets originate’ and ‘How were galaxies and black holes formed in the young Universe?’ A new generation of telescopes – just…

The largest galaxies in the Universe feed off cosmic oceans, which helps them grow. This is the presumption of an international team of scientist with two Leiden astronomers, based on observations of the ‘Spiderweb’ galaxy. The researchers published their evidence in Science on 2 December 2016.

An international team of more than 200 astronomers from 18 countries has published hundreds of thousands of unknown galaxies. The data are part of a project lead by Leiden professor of Observational cosmology Huub Röttgering. Both Dutch and international media reported extensively about the publica…

The Dutch-Japanese made DESHIMA instrument has passed its first practical tests when measuring the distances and ages of distant galaxies. The core of the instrument is a chip the size of two euro coins that measures 49 shades of far infrared light. The developers of the spectrometer publish the results…

ESA’s Gaia mission has produced the richest star catalogue to date, including high-precision measurements of nearly 1.7 billion stars and revealing previously unseen details of our home Galaxy.

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.’

Promotor: W. Jaffe, Co-promotor: K. Meisenheimer

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.

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

In astronomy, the interpration of observations and measurements plays a crucial role: we rely purely and fundamentally on the information that reaches us as observers. And 80% of all matter in the universe is undetectable directly.

Promotor: A. Achúcarro Co-promotor: A. Boyarsky

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…

Finally we know for sure that there is a black hole at the centre of our own galaxy. Today, astronomers unveiled the first ever photo of Sagittarius A*, a super-massive object at the centre of the Milky Way. This picture could only be taken thanks to the cooperation of telescopes worldwide.

Isabel van Vledder and Dieuwertje van der Vlugt, 2 astronomy students from Leiden University, have mapped the entire Milky Way galaxy in dwarf stars for the first time. This result is the most comprehensive model ever for the distribution of these stars. The findings appear in a new paper in Monthly…

What’s the fate of our sun, when in 5 billion years from now our Milky Way will clash with the Andromeda Galaxy? Leiden astronomers have been working on calculations on this collision. They recently gave a visual sneak preview on a big tech conference.

Benson van der Bij is a family member of Holland's most famous master: Rembrandt van Rijn. What does he think of this relationship? And did he know that Rembrandt was also enrolled as a student here?

On 27 November 2019, David de Boer defended his PhD dissertation 'Religious Persecution and Transnational Compassion in the Dutch Vernacular Press 1655-1745'. For his research, he analysed several hundred pamphlets, newspapers and periodicals published primarily in the seventeenth-century Netherlands,…

Promotor: Prof.dr. S. Portegies Zwart

Promotor: P. T. de Zeeuw, Co-promotor: N. Neumayer; G. van de Ven

Cosmologists have many possible models for the Universe, of which only one can be true. A new flowchart will eliminate some of them when two specific Universe features are accurately measured. Publication in Physical Review D on 7 November.