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

Promotores: Prof.dr. A.G.G.M. Tielens, Prof.dr. L.B.F.M. Waters (UvA), Prof.dr. C. Dominik (UvA)

My work focuses on a class of astronomical objects called protoplanetary disks.

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.

To study how planetary systems come into existence we study much younger systems still in formation.

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…

The zoo of detected exoplanets reveals both the uniqueness of our own Solar System and the complexity of planetary system formation, sparking fundamental questions about how planetary systems form and evolve.

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

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

Promotor: C.U. Keller, Co-Promotor: F. Snik

Many protoplanetary discs in which new planets are formed are much smaller than thought. Using the Atacama Large Millimeter/submillimeter Array (ALMA) scientists of the Leiden Observatory looked at 73 protoplanetary discs in the Lupus region.

Protoplanetary disks are the gas and dust environments where planetary systems form around young stars. Using observations from the Atacama Large Millimeter/submillimeter Array (ALMA) this thesis analyses the gaseous molecular reservoir, using multiple tracers to resolve the 3D structure of protoplanetary…

Planets are formed in disks of gas and dust around young stars.

Promotor: E. F. van Dishoeck, Co-promotor: C. Walsh

In the discs of dust and gasses around young stars, mysterious structures occur. Together with professor Ewine van Dishoeck, PhD student Paolo Cazzoletti investigate how we can explain these forms, such as rings, spirals and holes. On 12 December, he will defend his thesis.

Detecting planets during their formation stages is crucial for understanding the history and diversity of fully developed planetary systems like our own. However, observing young planets directly is challenging because they are often deeply embedded within their host protoplanetary discs, rich in gas…

To address the fundamental questions of how life on Earth emerged and how common life may be in the Universe, it is crucial to know the chemical composition of the planet-forming material.

Research using the ALMA telescope by scientists including Leiden's John Tobin and Steven Bos has produced the first images of the water snow line within a protoplanetary disc. Publication in Nature on 14 July.

What do scholars, the Netherlands Public Prosecution Service, the police, the National Rapporteur Human Trafficking, Victim Support Netherlands, and the Violent Offences Compensation Fund have in common? They all work with victims, each from their own expertise. High time to combine that knowledge,…

Promotores: Prof.dr. E.F. van Dishoeck, Prof.dr. C.P. Dullemond

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

The formation of stars and planets happens over multiple scales, which can interact. In particular, planet formation happens in the dense, complex environment of star forming regions.

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…

Lars van Doorn, research staff member at the Department of Economics at Leiden University, is shortlisted for the Daniël Heinsius Prize for the best master thesis of the Netherlands and Flanders.

Astronomy began by studying the light from the stars. These stars are born in vast clouds of gas and dust.

Starting 1 October 2022, Mirjam Sombroek-van Doorn has been appointed as Professor Law and Health.

From 13 to 16 July, Leiden will host the EuroScience Open Forum (ESOF), the largest multidisciplinary scientific conference in Europe. Lars van Doorn from Leiden Law School will give a presentation.

Researchers from the Department of Economics and the Institute of Public Administration – Olaf van Vliet and Lars van Doorn – have been awarded a grant of 430,000 euros from Instituut Gak to analyse the flexibilisation of the labour market and its implications for social policy.

This thesis takes steps toward understanding the interaction between gas-phase and solid-state molecules in star- and planet-forming regions.

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

We have conducted a full spectral line survey of the 3-13 micron region of two massive protostars, AFGL 2591 and AFGL 2136, for the first time at high spectral resolution.

The focus of this thesis is how stars like our Sun and planets like Jupiter, Saturn, and Earth are formed.

This thesis is a (biased) journey through very different topics in astrophysics: quasars and new populations of active galactic nuclei, gravitational waves from merging black holes, and protoplanetary discs around young stars.

High-angular-resolution observations of the circumstellar material have uncovered numerous and very diverse substructures in protoplanetary discs, raising the question of whether they are caused by forming planets or other mechanisms.

In the disk surrounding the young star WISPIT 2, not one but two planets are taking shape. Leiden PhD candidate Richelle van Capelleveen played a key role in this discovery, providing a rare glimpse into the early stages of planetary system formation.

Circumstellar discs are the reservoirs of gas and dust that surround young stars and have the potential to become planetary systems.

Planet formation is a surprisingly homogeneous process that does not take place gradually from inside out, but that occurs everywhere at the same time in a proto-planetary disc, as Dave Lommen has discovered. He will obtain his doctorate this week based on his research into the dust around young stars…

eLaw - Center of Law and Digital technologies from Leiden Law School, and the Vascular Surgery Department at Leiden University Medical Centre in the Netherlands, join forces to explore the use of AI for diabetes and secondary prevention of diabetic foot problems and won a prize for it.

All comets might share their place of birth, new research says. For the first time ever, astronomer Christian Eistrup applied chemical models to fourteen well-known comets, surprisingly finding a clear pattern. His publication has been accepted in the journal Astronomy & Astrophysics.

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.

This research project is funded by a subsidy from Instituut Gak.

Astronomer Jos de Boer has received the Chesneau Prize in Nice for his research into so-called protoplanetary disks. The prize is awarded to the best astronomical dissertation in the field of high angular resolution. 'I consider it a good opportunity to talk about my research.'