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 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

What is the origin of solar systems?

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.

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

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

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

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…

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

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.

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.

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.

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

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

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.

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

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.

Presenters will be expected to give a proper introduction of the project and describe their aims in a clear and concise manner. Progress and problems will be addressed to evoke a discussion. Undergraduate students are also supposed to present their work when their daily supervisor is scheduled.

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At our regular panel discussions we bring together scholars and other experts to discuss a current topic that captures the interest of the general public as well as academics.

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…

Walsh

Recently, Europe was again shaken by some attacks. This ‘Elementair Deeltje’ places terrorism in a historical perspective and gives an up-to-date overview of this form of political violence.

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.

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.'

PhD defence

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…

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…

This article aims to provide a coherent foundation for empirical studies of interpersonal discussion on risk.

Promotor: Prof.dr. E.F. van Dishoeck, Co-Promotor: M.R. Hogerheijde

A team of European astronomers under Leiden leadership has discovered that dust particles around a star already coagulate before the star is fully grown. These agglomerated dust particles are the first step in the formation of planets. The research publish their discovery in the journal of Nature As…

On 24 November 2015, Prof. Carsten Stahn participated as external expert in a special plenary session of the Assembly of States Parties on the efficiency and effectiveness of Court proceedings, chaired by the co-chairs of the Study Group on Governance of the Assembly.

This thesis describes the development and validation of new high-contrast imaging techniques, with the ultimate goal of enabling the next generation of instruments for ELT-class telescopes to directly image Earth-like extra-solar planets orbiting around nearby stars.

An international team of astronomers including Leiden scientists publishes the image of a young star with a surrounding dust disk that is still being fed from its surroundings. The phenomenon around the star SU Aur may explain why so many exoplanets are not neatly aligned with their star. The European…

Free childcare: Professor Egbert Jongen sees the potential drawbacks. The allocated budget could be used more effectively, for one thing. He discusses this issue at length with Geert de Wit in Dutch financial newspaper ‘Het Financieele Dagblad’.

From 21-22 September 2016, The INSOL Europe Academic Forum met in Cascais (Portugal). The Business Rescue in Insolvency Law project team of the European Law Institute was present with two research assistents.

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…

Always wanted to give your input on sustainability for the university's new Strategic Plan? Join LUGO's discussion session!

Rector Magnificus Carel Stolker retired on 8 February. If there was one theme running through his career, it was the links between the University and society. Before he left, Stolker spoke one last time to people from within and without the university about the societal impact of research. On topics…

With 8.9 million euros from the Danish National Research Foundation, Aarhus University and Leiden Observatory will establish the Center for Interstellar Catalysis. The centre is led by Aarhus professor Liv Hornekær and aims to find out how and when the building blocks of life formed in the Universe.…

On 13 June, Professor Christa Tobler spoke about indirect discrimination at the Vilnius Gediminas Technical University in Lithuania.

In 1968 Japan was shocked by student protests and even today, exactly fifty years later, their effects can still be felt. An interdisciplinary group of researchers recently met to discuss them at Leiden University.