Dr Joris Witstok

Astrophysicist studying the formation of the first stars, black holes and galaxies in the Universe with the largest telescopes on Earth and in space.

Cambridge

About me

I am currently a postdoctoral research fellow (DAWN Fellow) at the Cosmic Dawn Center, affiliated with the Niels Bohr Institute at the University of Copenhagen. Previously, I was part of the Cavendish Laboratory, University of Cambridge, working with Roberto Maiolino and Sandro Tacchella within the Kavli Institute for Cosmology. I completed my PhD at Sidney Sussex College, supervised by Renske Smit and Roberto Maiolino.


My research interests revolve around galaxy formation and evolution in the early Universe: how the first stars and galaxies were formed, how they for the first time synthesised elements heavier than helium, and how they subsequently brought about the Reionisation of the Universe, a major phase transition that turned the neutral Universe back to a (mostly) ionised state.

Extragalactic astronomy

Learn more about my research.

For public:
An introduction to extragalactic astronomy

What is a galaxy?

How do we learn about the first galaxies in the Universe?

For scientists:
My research

The build-up of metals and dust in the early Universe

The role of galaxies in Cosmic Reionisation

News & Media

Discovery of the most distant galaxies currently known

Finding carbon-rich dust grains in the early Universe

Contact

For pressing existential or practical questions