Pascal Oesch

Pascal Oesch is an Associate Professor at the University of Geneva and at the Cosmic DAWN Center at the University of Copenhagen. He leads an observational research group “Galaxy Build-up at Cosmic Dawn” which focuses on understanding the build-up and assembly of the very first generations of galaxies based on panchromatic observations including data from the James Webb Space Telescope. He received his PhD in 2010 from ETH Zurich, before moving as a Hubble fellow to the University of California, Santa Cruz. After a YCAA fellowship at Yale, he moved back to Switzerland in 2016.

The First Chapters of Galaxy Build-up Revealed by JWST

The first deep images with the James Webb Space Telescope (JWST) have transformed our view of the Universe. With its unparalleled imaging and spectroscopic capabilities, JWST immediately extended our cosmic horizon into uncharted territory, with galaxies confirmed to z~14 and candidates identified out to z~16, only ~250-300 Myr after the Big Bang. We are thus at the brink of finding the first galaxies that ended the cosmic Dark Ages and started the reionization of the Universe. In this talk, I will provide a short overview of some of the key breakthroughs in early galaxy build-up based on the first years of JWST data.