The 'deepest and sharpest' image of the Universe to date: the first photos from the new James Webb space telescope yesterday mesmerised astronomers and the public alike. Leiden Professor of Molecular Astrophysics, Ewine van Dishoeck, spoke to various media outlets about the first images, which include…

A team of European astronomers has found a silicate-based weather system on a cloudy gas planet around the star WASP-107. It is the first time astronomers have found silicate clouds and rain. They also conclude that temperatures deeper in the atmosphere are rising rapidly. 'The presence of clouds has…

An international team of astronomers, led by Will Rocha of Leiden Observatory, using the NASA/ESA/CSA James Webb Space Telescope have discovered that the key ingredients for making potentially habitable worlds are present in early-stage protostars, where planets have not yet formed.

James Webb life’s building blocks

Lecture, Oort lecture

From the birth of the universe to the molecules in a planet's atmosphere. The first five pictures from the James Webb Space Telescope (JWST) show the enormous range in which the space telescope can operate. Ewine van Dishoeck, professor of molecular astrophysics, took a look at the first images Tuesday…

How do galaxies form? That is what astronomer Mariska Kriek will be researching in the coming years. She received an NWO Vici grant of 1.5 million euros to study galaxies in the early universe. ‘This research uses new and unprecedented observations from the James Webb Space Telescope (JWST). These allow…

A star does not just appear in the sky overnight. Its creation takes tens of thousands of years. Twenty years ago, astronomers took a picture of a star in its birth phase. The James Webb Space Telescope (JWST) could now capture that same star in much greater detail. This does not only provide beautiful…

An international team of astronomers including Leiden professor Ewine van Dishoeck has observed the benzene molecule (C6H6) in a planet-forming disk around a young star for the first time. The observations tell us more about the forming of planets in this disc, like our own Earth. The scientists publish…

An international team of astronomers led by Ardjan Sturm of the Observatory has made the first two-dimensional inventory of ice in a planet-forming disk of dust and gas surrounding a young star. The researches, including Melissa McClure, used the James Webb Space Telescope and publish their findings…

An international team led by astronomers at Leiden University has shown in laboratory experiments that sulfur can bind with ammonium under icy cosmic conditions and form a salt that sticks to dust and pebbles. The resulting sulfur salt not only helps to explain the mystery of the missing sulfur gas,…

A group of astronomers led by Leiden PhD student Sebastian Zieba has discovered using the James Webb Space Telescope (JWST) that the rocky exoplanet TRAPPIST-1 c has a thin atmosphere. Although the planet is nearly identical to Venus in size and temperature, and was expected to have a thick atmosphere,…

For over a year now, the James Webb Telescope has been sending stunning images that exceed astronomers’ expectations. The photos are fascinating to see, but what exactly are we looking at? Assistant professor Melissa McClure explains.

A team led by Leiden University in the Netherlands and the National Radio Astronomy Observatory have, for the first time, robustly detected semi-heavy water ice around a young sunlike star. In this ice, some of the ordinary hydrogen atoms have been replaced by deuterium, a heavier variant of hydroge…

How do molecules originate and evolve in space? And how does that ultimately determine the chemical composition of planets and their atmospheres? The Dutch Astrochemistry Network (DANIII) receives 1.6 million euros from NWO to find out. A large group of Leiden astronomers and chemists is contributing:…

Two teams of astronomers, including one from Leiden University, have discovered oxygen in the most distant known galaxy, JADES-GS-z14-0. This groundbreaking discovery shows that galaxies could form much faster in the early universe than was previously thought.

Protostars, data science, and the James Webb Space Telescope—Adriaan Janssen’s curiosity knows no bounds. As a double bachelor’s student in Physics and Astronomy, he has truly found his calling, underscored by his nomination for the title of Leiden Science Young Talent 2024.

The James Webb Space Telescope continues to surprise us with stunning pictures, but of what exactly? Astronomer Nienke van der Marel shows with three images how massive stars lead short but explosive lives.

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.

Could water be present in planet-forming disks before the formation of rocky planets? The James Webb Space Telescope may have found evidence for that. Webb has for the first time observed water in the inner disc around young star where at greater distance, giant planets have already formed. The research…

Large pairs of planets thought to orbit each other without a star, do not exist after all. That conclude Leiden researchers, after extensive computer modelling and simulations. What the double dots seen by the James Webb Space Telescope are, remains a mystery.

They hurtle along at over a thousand kilometres per second: the fastest stars in the Milky Way. PhD candidate Fraser Evans conducted research into these elusive hypervelocity stars and discovered that they have a lot to teach us, about black holes and supernovae, for example.

Astronomers have found complex organic ice outside the Milky Way for the first time. The discovery shows that the building blocks of life could arise early in the universe - and under a variety of conditions, said Leiden astronomer Will Rocha.

ESA’s space telescope Gaia, which maps the Milky Way, completes its active phase of scanning the sky on 15 January. Over the past decade, Gaia has made more than three trillion observations of about two billion stars and other cosmic objects. ‘Gaia is already the discovery machine of the decade,’ Leiden…

International researchers have, for the first time, pinpointed the moment when planets began to form around a star beyond the Sun. Using the ALMA telescope, in which the European Southern Observatory (ESO) is a partner, and the James Webb Space Telescope, they have observed the creation of the first…

Your space for a confidential conversation.

To look for atmospheres around planets outside our solar system is to look for extraterrestrial life. Astronomist Sebastian Zieba used data from the James Webb Space Telescope to study small rocky exoplanets but found no aliens yet. However, his findings are still very interesting for future observations.…

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,…

The two instruments of ESA's space telescope Euclid have taken their first test images. The first images indicate that the space telescope will achieve the scientific goals for which it was designed - and possibly much more. Euclid will create a 3D map of a third of the sky, allowing scientists to study…

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.

University Library, Witte Singel 27, 2311 BG, Leiden

Do you want to contribute to society and do you have affinity with space? In the LDE Space & Society Honours Programme, you will learn how the two are connected and tackle a challenge in the space sector.

Study spaces

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.

Study spaces