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…

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

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.

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

The discovery of a planet far too large for its sun defies models about the formation of solar systems and planets. In a paper in Science, researchers, including Yamila Miguel of Leiden Observatory, report the discovery of a planet more than 13 times heavier than Earth orbiting the ultracool dwarf star…

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

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

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…

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…

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 In this ice, some of the ordinary hydrogen atoms have been replaced by deuterium, a heavier variant of hydroge…

In Germany, the United States and even in Vietnam: all over the world, the Leiden discovery of the birth of two planets was shared. Astronomer Sebastiaan Haffert and his team were able to record multiple planets in the making for the first time and published their findings in Nature Astronomy. A unique…

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.…