From children’s birthday parties to international ambassadors, the Old Observatory attracts a wide range of visitors. Student coordinator Sanne van Beek connects visitors and students, ensuring everyone — from five to sixty-five — learns something about the stars.

Jasper Knoester is the dean of the Faculty of Science. How is he doing? What kinds of things is he doing and what does his day look like? In each newsletter Jasper gives a peek into his life as dean.

From telescopes to science fiction: in just one semester, students with no background in physics or astronomy get to explore the universe. The first group of students started last month in the new minor Our Universe.

From lectures by Robbert Dijkgraaf to a telescope on the ocean floor: during his double bachelor’s in Physics and Astronomy, Jelle Oonk discovered that the path to big cosmic answers sometimes runs through the smallest, hardest-to-catch particles—neutrinos.

An international team of astronomers led by Violeta Gámez Rosas (Leiden University) has observed a supermassive black hole hidden in a ring of dust. This discovery fits the idea that the so-called active centers of galaxies are much more similar than observations show, because the viewing angle from…

Researchers using NASA’s James Webb Space Telescope may have detected atmospheric gases surrounding 55 Cancri e, a hot rocky exoplanet 41 light-years from Earth. This is the best evidence to date for the existence of any rocky planet atmosphere outside our solar system.

The Dutch Research Council (NWO) has awarded Vidi grants to 14 Leiden researchers. This grant of a maximum of 850,000 euros will enable them to start a new research group and develop their own line of research over the next five years.

The night side of exoplanet WASP-43b, to the surprise of astronomers, does not appear to contain methane. It is likely that extreme winds do not allow enough time for methane to form in detectable amounts. This is the conclusion of an international team of scientists, with Leiden and Amsterdam contributions,…

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.

An international team of astronomers has discovered a large reservoir of hot gas in the cluster-in-formation around the Spiderweb Galaxy. Based partly on that hot gas, the astronomers predict that the cluster-in-formation will grow into one of the largest objects in the universe. A step closer to discovering…

An international team of researchers led by astronomers from Leiden University (the Netherlands) has produced the first sharp radio maps of the universe at low frequencies. Thanks to a new calibration technique, they bypassed the disturbances of the Earth's ionosphere. They used the new method to study…

The shock wave triggered by one of the five galaxies making up the iconic Stephan’s Quintet appears to be less disruptive than previously thought, with the shock likely being cushioned by dust particles in the surrounding gas. This is according to the analysis of the first scientific observations of…

Does gravity work the same when you look at the largest scales in our universe? That’s what Leiden physicist Alessandra Silvestri will study with a 2 million euro ERC Consolidator grant. ‘We assume that it does, but we don’t actually know.’

Speculation about alien life, a new nitrogen map, AI as a thesis supervisor, groundbreaking telescopes and multi-million-euro investments to combat antimicrobial resistance – the diversity of these topics shows that our readers are just as broadly interested as our researchers. Discover the most-read…

The fact that scientists are increasingly better able to access molecular cell and tissue data also brings with it a new challenge: how can scientists find the information they need for research among the vast amount of data available?

How do you progress from an immense gas cloud somewhere in the universe to a star with planets? Research by Astronomy PhD student Martijn van Gelder sheds more light on the earliest phases of this process. He will receive his doctorate on November 24th.

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.

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.

PhD defence

Are magnetic fields older than the first light? And how did they influence the development of our universe right after the Big Bang? Cosmologists from Leiden, Groningen, and Utrecht are now collaborating to investigate this.

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…

The Dutch Research Council (NWO) is investing 197 million euros in 11 infrastructure projects that will be of great value to science and society. Leiden University and the Leiden University Medical Center (LUMC) are participating in eight of the eleven proposals.

For the first time, an international group of astronomers have seen the heat glow of two ice giant planets colliding. They could also observe the resultant dust cloud move in front of the parent star several years later. Led by Leiden astronomer Matthew Kenworthy, they monitored the star's brightness…

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.

Emeritus Professor of Molecular Astrophysics Ewine van Dishoeck has been named a Citation Laureate by Clarivate, a research analytics provider. Clarivate considers her an influential researcher of the calibre to win a Nobel Prize.

Can a robot rekindle the waning interest in Buddhism in Japan? University lecturer Peter van der Putten researches the philosophical and social questions related to artificial intelligence. He also investigates whether computers and robots can take over creativity, emotions and other human characteristics.…

The Dutch Research Council (NWO) has awarded Vidi grants to Leiden researchers.

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 have used data from the European Gaia Space Telescope to discover 55 high-speed stars launched from the young star cluster R136 in the Large Magellanic Cloud, a satellite galaxy of the Milky Way. This increases tenfold the number of known “runaway stars” in this region. The team of astronomers,…

An international team of astronomers led by Dutch scientist Martijn Oei has discovered the largest pair of jets from a black hole ever seen. The 'jumbojets' extend a combined length of 140 Milky Ways. The Leiden Observatory played a prominent role in this research. The publication will feature on the…

The European Space Agency (ESA) has published an interim data release from Gaia, the space telescope mapping out the Milky Way in 3D. The first scientific papers published today reveal half a million stars in the Omega Centauri globular cluster, nearly 400 candidate gravitational lensers and the positions…

On March 13, Dr. Erik Deul passed away at the age of 67. He leaves behind his wife Wilma, children Caroline and Wouter, and grandchildren Joris, Stach, Viggo, Archie and and a granddaughter expected later this year. Erik served as head of ICT at Leiden Observatory for 35 years, and later also at the…

PhD defence

An international team of astronomers, including astronomers from Leiden University, has found the missing link in the path taken by water through star-forming clouds and young stars to comets and planets. They did so with the help of the ALMA observatory in Chile. The researchers published their findings…

Leiden professor of molecular astrophysics and astrochemistry Ewine van Dishoeck was presented with the Niels Bohr International Gold Medal on Friday 7 October. The medal, instigated by the Danish Society of Engineers IDA, was awarded by Queen Margrethe of Denmark at a ceremony at the Carlsberg Academy…

LIACS assistant professor Ben van Werkhoven leads the development of software for optimising graphics processing units. By now, version 1.0 of 'Kernel Tuner' is just around the corner. This milestone shows that the software is ready for serious use.

A team of scientists, including Leiden Astronomer Alice Booth, has discovered silicon monosulfide molecules in the dust disk around a young star. Such molecules indicate planet formation. The team made the discovery using the ALMA telescopes. This method provides an alternative when direct observation…

Using the James Webb Space Telescope, an international team of researchers, including Leiden Professor of Molecular Astrophysics Ewine van Dishoeck, has discovered a palette of hydrocarbons in a planet-forming disc around a young, low-mass star. The results confirm that discs around very lightweight…

Lenses from Christiaan Huygens’ telescope, instruments used to demonstrate Newton’s laws, and equipment that led to the discovery of superconductivity—around 3,000 scientific instruments from the Faculty of Science at Leiden University are now officially part of the Rijksmuseum Boerhaave collection.…

A team of international researchers led by Tomas Stolker in the Netherlands has imaged a young gas giant exoplanet near a 12-million-year-old star. The planet is orbiting a star at which planet formation has finished, while the same-aged companion star still has a planet-forming disk. The researchers…

Astronomers at Leiden University have detected rare isotopes of carbon and oxygen in our neighbouring stars for the first time, providing a new window to better understand the chemical evolution of the cosmos.The results are published today in the journal Nature Astronomy.

Prof Harold Linnartz has been reappointed Director of Education of the bachelor and master programmes of Astronomy. The appointment is for a period of four years, until 1 October 2026.

Beautiful prizes, special speeches, and a reception with live music. The well-attended Leiden Science New Year's reception was a delightful way to start the year 2023. Dean Jasper Knoester opened the event after which it was announced who were chosen teacher and bachelor student of the year.

How does astronomy benefit you? The new single-episode podcast Cosmic Perspectives explores the impact of Dutch astronomy on society: from building positive international relationships to the transfer of life-changing technology.