The Sun and all the stars in the night sky reside in the Milky Way galaxy. In the at-rest reference frame of the Galaxy, typical stars travel with velocities of about 100-200 kilometres per second.

This thesis describes the implementation and on-sky demonstration of high-resolution integral-field spectroscopy for extreme adaptive optics systems that are used to find and characterize exoplanets.

In the past decade many population studies have been performed with the Atacama Large Millimeter/submillimeter Array (ALMA) to understand the bulk properties of protoplanetary disks around young stars. These population studies mostly consisted of low mass stars, with relatively few of the disks around…

This thesis investigates the evolution and fate of gaseous exoplanets, which are continuously shaped by stellar activity across both short and long timescales.

A plasma is an ionized gas with very low electrical resistivity. As such, magnetic field lines are 'frozen in' and move with the fluid. Magnetic field lines that are linked, knotted and tangled, cannot be undone by the fluid motions.

Forming at the nodes of the Cosmic Web and growing hierarchically via mass accretion, galaxy clusters are the largest virialized halos in our universe, composed of dark matter (DM; ≥85%), ionized hot plasma in the intracluster medium (ICM; ≥10-15%), and galaxies (≥1-5%).

After years of development, the moment has finally arrived: a massive cryostat, a highly advanced freezer that keeps the sensitive components extremely cold, has arrived in Leiden from Zurich. The device is the largest component of METIS, one of the first instruments for ESO’s Extremely Large Telescope…

Minuscule elementary particles from space colliding with Earth can give us an insight into the distant objects they come from. But first, you need to know how to catch them. With a Vidi grant from NWO, researcher Sjoert van Velzen will 'hunt' for neutrinos coming from exploding black holes.

The highly successful deep-sea telescope KM3NeT can now expand both its size and scope. Using a new type of microphone for underwater use, the telescope will attempt to detect the sound produced by neutrinos as they travel through the sea. The data collected will also be of great interest to other research…

The highly successful deep-sea telescope KM3NeT can now expand both its size and scope. Using a new type of microphone for underwater use, the telescope will attempt to detect the sound produced by neutrinos as they travel through the sea. The data collected will also be of great interest to other research…

Leiden Observatory is the astronomical institute of the Faculty of Science of Leiden University.

Mathematician Robbin Bastiaansen, physicist Irene Battisti, pharmacist Fouzia Lghoul-Oulad Saïd and physics and astronomy student Maite Boden are the winners of the annual prizes of the Faculty of Science. Boden was honoured as the first Young Star, a new prize for the best bachelor’s student of the…

With his clever measuring methods Ignas Snellen – together with his team – was the first to detect carbon monoxide in the atmosphere of exoplanets. For his pioneering work the Leiden astrophysicist has been awarded the Spinoza Prize, the highest academic honour in the Netherlands. The prize of 2.5 million…

This is an Erasmus+ International Credit Mobility project of the Faculty of Science with two universities in Armenia.

At Leiden Observatory, researchers investigate the origin of stars and their planetary systems. They detect and characterize planets around other stars (exoplanets). They study how stars and planets form. And they follow molecules from interstellar clouds to nascent planet systems. This way they address…

Researchers at Leiden Observatory study the fundamental physics that creates structure in the Universe. These processes collect matter into galaxies and gas into stars. With the use of powerful telescopes and advanced calculations and computer simulations, Leiden astronomers seek to understand the origin,…

Of the 111 Spinoza Prizes that have been awarded since 1995, 28 have gone to researchers from Leiden University.

These are the proposed research projects for LEAPS 2019. Please note that not all projects will go ahead and some may still be added in the near future. Final funding decisions lie with the Faculty sponsors. And please make a note that if you are interested in an ESA project, to check if your state…

Are you interested in taking up an extra challenge during your Astronomy master’s programme? Have you thought about applying for our Summer School programme or are you interested in developing your personal leadership style?

Are you interested in taking up an extra challenge during your master’s programme? Have you thought about applying for our Summer School programme or are you interested in developing your personal leadership style?

Are you interested in taking up an extra challenge during your Astronomy master’s programme? Have you thought about applying for our Summer School programme or are you interested in developing your personal leadership style?

Are you interested in taking up an extra challenge during your Astronomy master’s programme? Have you thought about applying for our Summer School programme or are you interested in developing your personal leadership style?

Are you interested in taking up an extra challenge during your Astronomy master’s programme? Have you thought about applying for our Summer School programme or are you interested in developing your personal leadership style?

By carrying out fundamental research and providing excellent education, universities become a breeding ground for innovation and entrepreneurship.

Promotor: Jelle S. Kaastra Co-promotor: Jelle de Plaa

For centuries astronomers studied the Universe by collecting light. Nowadays, we are living in times of great technological advancements, which allow us to explore our Universe in a new way - though gravitational wave radiation.

This thesis focuses on protoplanetary disks: flattened structures of gas and dust around young stars in which planets are expected to form and grow.

In this thesis, the research focuses on the properties of dark matter and dark matter haloes and how they connect with the galaxies we can observe in the Universe.

Promotores: S.F. Portegies Zwart, E. M. Rossi

Until the 1990s, the only known planets were those in our Solar System. Three decades later, several thousand exoplanets have been discovered orbiting stars other than the Sun, and substantial efforts have been made to explore these strange new worlds through spectroscopic analyses of their atmosphe…

Outflows are crucially important for the gas budget and evolution of luminous star-forming galaxies and AGNs, with observed mass outflow rates of the same order as the star formation rate. Greater star formation and black hole growth lead to more intense feedback and outflows, resulting in self-regulated…

I have studied the hot, diffuse gas around and between galaxies. Specifically, I have used the EAGLE numerical simulations of galaxy formation to predict the properties of this gas, and I have used those properties to predict specific observables: soft X-ray absorption and emission lines.

The work presented in this thesis is based on ALMA surveys of protoplanetary disks in three star-forming regions: Lupus, OMC-2, and NGC 2024.

Promotor: J.S. Kaastra Co-promotor: E. Constantini

Stars like the sun are born in large molecular clouds existing from gas and dust. During the formation process, the chemical composition of the material can be altered drastically by the changing physical conditions.

Understanding the formation and evolution of planetary systems is one of the most fundamental challenges in astronomy. To directly image and study young exoplanets and the circumstellar disks they form from, dedicated high-contrast imaging instruments are built.

This thesis examines the link between simple molecules and the underlying structure and chemistry within protoplanetary disks - the birthplaces of planets.

This thesis discusses the physical and chemical processes than influence the composition of forming planets.

Complex Organic Molecules (COMs) have been detected in objects across different stages of stellar evolution.

Low-mass main-sequence stars like our Sun are continuous sources of outflowing hot magnetised plasma. In the case of the Sun, this is known as the solar wind, whereas for other stars they are called stellar winds.

This research focuses on the distribution of chemical elements in protoplanetary disks, the birthplaces of planets. These disks form around young stars and contain gas and dust, from which planets grow. Ice plays a crucial role in planet formation, aiding the clumping of dust particles and influencing…

This dissertation is an experimental study of laser-generated, atmospheric pressure, transient toroidal helium plasmas.

Promotor: Prof.dr. I.A.G. Snellen, C.U. Keller

This thesis focusses on the temperature structure in protoplanetary disks. The relation between structures seen in the dust and gas-phase molecules is investigated.

A dense region of a gaseous and dusty cloud collapses to form a protostar surrounded by a disk and an envelope. This thesis uses both observations and models to study physical and chemical conditions of these protostellar systems which are likely where planets start to form.

One of the key discoveries in exoplanet research over the past decade is the abundance of small planets in our Milky Way. Despite their high numbers, our understanding of their atmospheres remains limited, and it is unknown if they possess atmospheres at all.

Tracing the evolution of the molecular gas content in galaxies is critical for a complete understanding of galaxy formation and evolution, as it provides the direct fuel for star formation. Studies of high-redshift (z>1) molecular gas reservoirs, most commonly traced by carbon monoxide (CO), have seen…

A large diversity of exoplanetary systems has been found, but it is still unclear what drives this diversity.

The physical origin of the dozens of stellar-mass binaries, the mergers of which have been detected by the LIGO-Virgo-KAGRA collaboration via gravitational waves, is still unknown.

This thesis addresses the chemical processes that determine the compositions of giant planet atmospheres.