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School of Physics and Astronomy

Dr Sijme-Jan Paardekooper


Royal Society University Research Fellow and Senior Lecturer

Telephone: 020 7882 6575
Room Number: G. O. Jones Building, Room 503


I am a Royal Society University Research Fellow and Senior Lecturer at Queen Mary, University of London. I am interested in figuring out how planets form, both in the Solar system and beyond. My research therefore focuses on discs around young stars, which are thought to be the birthplaces of planets. I study the various physical processes involved using state-of-the-art numerical methods.

I completed my PhD at Leiden University, in the Netherlands, in 2006. This was followed by a stint at the Department of Applied Mathematics and Theoretical Physics in Cambridge, first as a research associate, then as an STFC postdoctoral fellow, and finally as a Royal Society URF. I joined Queen Mary in 2013.


Extrasolar Planets and Astrophysical Discs (SPA7009)

Over the past 25 years, roughly 3500 (!) planets have been discovered orbiting stars other than our Sun. Planets appear to be almost everywhere we look: from our nearest neighbour star, to stars invisible to the naked eye; orbits range from extremely close ('Hot Jupiters') to extremely wide (~100 Astronomical Units). The most common planet in our galactic neighbourhood may well be a planet that we do not have in the Solar System: a Super-Earth. All these surprising discoveries make us think about how this zoo of extrasolar planets was formed.

Young stars are known to be surrounded by discs of gas and dust. These are thought to be the sites of planet formation. In order to understand the formation of planets, both in the Solar System and beyond, we have to understand the dynamics of astrophysical discs. Such discs play in many astrophysical systems, such as Cataclysmic Variables, Active Galactic Nuclei, around planets (Saturn!). This makes them interesting objects of study in their own right.


Research Interests:

Extrasolar Planets

The population of planets around stars other than our Sun has thrown a lot of surprises at us: Hot Jupiters, Super-Earth, planets in close binaries, circumbinary planets, and many more types of planetary systems very much unlike our own Solar system. My research focuses on trying to understand this zoo of exoplanets by looking at how they formed: in accretion discs around young stars.

Protoplanetary discs

Discs around young stars consist of gas and, initially, tiny dust particles that can be found in the interstellar medium. These tiny dust particles will have to grow 14 orders of magnitude to become Earth-like or even giant planets. I study the important processes for growing planets and shaping planetary systems with the help of computer simulations.

Numerical hydrodynamics

Protoplanetary discs consist, at least initially, for 99% of gas. Computer simulations of protoplanetary discs therefore solve the equations of hydrodynamics. Part of my research is to try and develop new techniques for solving these equations, both on traditional CPUs and graphics cards.



This is not an exhaustive list and I would be happy to discuss other project possibilities.