Galaxies are environments where gas coalesces, cools, and is converted into stars. However, it remains unclear the exact mechanisms through which galaxies acquire, redistribute and lose their gas.

Promotor: Prof.dr. H. J. A. Röttgering, Co-Promotor: Dr. M. Haverkorn

This thesis is an experimental study of the UV irradiation of the interstellar ice analogues, relevant for the different stages of the star and planet formation sequence.

Promotores: Prof.dr. A.G.G.M. Tielens & Prof.dr. L. Kaper (UvA)

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

A century ago, it was unclear whether the stars in the sky were clustered in groups, or widely spread in the universe.

Promotor: Prof. dr. A.G.G.M. Tielens

Promotor: Prof.dr. A.G.G.M. Tielens, Co-Promotor: J.B.R. Oonk

Organic molecules in interstellar space are important as they influence the structure of galaxies and star formations. Studying catalytic processes in space allows us to understand how molecular species are formed and chemically evolved in the interstellar medium and solar system objects.

Promotor: H.V.J. Linnartz

The

This thesis is largely an experimental study on the formation of solid-state simple and complex organic molecules in the H2O-rich and CO-rich ice phases of dense interstellar clouds and dark cores.

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.

The solar system was formed approximately 4.56 billion years ago. Despite the numerous theories that have been developed over the years, the formation and evolution of the solar system still remain unclear.

The Low Frequency Array enables studies of low-frequency carbon radio recombination lines with unprecedented sensitivity, spectral and spatial resolution.

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

In this thesis chemical and physical processes in the ice mantles on interstellar dust grains are studied.

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

Laboratory, observation and modeling work on the dissociation of polycyclic aromatic hydrocarbons in interstellar environments and the formation of new molecular species through the fragmentation process.

Promotor: Prof.dr. H.L.V. Linnartz

Polycyclic aromatic hydrocarbons (PAHs) are the most abundant class of organic compounds in space. The PAH field evolves from the constant interaction between experimentalists, theorists, modellers and observers. While laboratory research and quantum chemical calculations together set up the molecular…

Promotor: M. de Jong, Co-Promotor: Samtleben

Promotor: Prof.dr. H.V.J. Linnartz, Co-Promotores: S. Ioppolo, H.M. Cuppen

Promotor: H.J.A. Röttgering, Co-promotor: G.K. Miley

Our in-house human skin equivalents contain all stratum corneum (SC) barrier lipid classes, but have a reduced level of free fatty acids (FAs), of which a part is mono-unsaturated. These differences lead to an altered SC lipid organization and thereby a reduced barrier function compared to human skin.…

Promotor: H.J.A. Röttgering, Co-promotor: M. Haverkorn

In Film and Video Intermediality, Janna Houwen innovatively rewrites the concept of medium specificity in order to answer the questions “what is meant by video?” and “what is meant by film?”

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

Stellar feedback is a crucial ingredient in the evolution of galaxies.

This dissertation provides a detailed description of the interaction between verb semantics and the two grammatical voice categories in the Vedic Sanskrit of the Rigveda.

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

Promotor: F.P. Israel, Co-Promoter: R. Meijerink

Dust particles in space form the basis for new stars and planets. But what do these particles consist of and how do they behave? Sascha Zeegers studied this. PhD defence 1 November.

The high velocity tail of the total velocity distribution of stars provides essential insight into fundamental properties of the Galaxy.

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

We simulate interstellar clouds with special plasma expansions and chemical reactions on icy dust grains to be measured in ultra-high vacuum setups. This provides the data necessary to guide and interpret astronomical observations and to model reaction networks in space. [Harold Linnartz]

When observing star-forming galaxies, we are not only seeing stellar light, but we also see how this interacts with galactic gas and dust. This thesis contains studies of the stellar, nebular and dust properties of low mass star-forming galaxies.

Lecture, Kaiser Lente Lezing

Professor Ewine van Dishoeck, together with an international team of colleagues, has written an overview of everything we know about water in interstellar clouds thanks to the Herschel space observatory. The article, published in the journal Astronomy & Astrophysics, summarizes existing knowledge and…

A revolutionary supercomputer with energy-efficient parts that are available in the shops. Professor of Computational Astrophysics Simon Portegies Zwart has been awarded an NWO Medium Grant to build this processing giant, which will have the power of a supercomputer but requires only one percent of…

At Leiden Observatory, researchers investigate the origin of stars and their planetary systems. They detect and characterize planets around other stars, which are called exo-planets. They study how stars and planets form. And they follow molecules from interstellar clouds to nascent planet systems.…

Astronomers from Leiden University have discovered that the star wind from a newborn star in the Orion Nebula prevents more stars from forming in the immediate vicinity. They made the discovery with data from the SOFIA observatory. This was announced by co-author Xander Tielens during a press conference…

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…

This thesis is about the study of hydrocarbons via infrared spectroscopy.

Research at the THEOR group is comprised of the following research themes: