This Nobel Prize makes EPFL's astrophysicists proud

“The plurality of worlds has left the realm of dreams to become an object of study.” Those were the words spoken by Michel Mayor at EPFL’s 2002 Master’s degree graduation ceremony as he described the discovery that he, along with Didier Queloz, made of the first planet located outside our solar system. Mayor was at EPFL to receive the title of doctor honoris causa. Yesterday, the two astrophysicists from the University of Geneva won the Nobel Prize in Physics for that very same discovery. The award also went to a third researcher in the same field, James Peebles, from Princeton University, for his “theoretical discoveries in physical cosmology.” Jean-Paul Kneib, the director of the Laboratory of Astrophysics (LASTRO) and of EPFL’s Space Center (eSpace), explains the significance of this news.

• Why does this Nobel Prize mean so much to EPFL?

Jean-Paul Kneib: First, it’s pretty uncommon for the Nobel Prize in Physics to be awarded in the field of astrophysics. So it’s an important accolade for this discipline as a whole and a real source of motivation for students who chose this field of research. The Nobel Prize did not go just to Michel Mayor and Didier Queloz, but also to James Peebles at Princeton for his work on the physical foundations of modern cosmology. The theoretical framework that Professor Peebles developed led to modern observational cosmology, one of the main directions of research at EPFL’s Laboratory of Astrophysics. One of our primary research objectives is to precisely measure, through repeat observations, the cosmological parameters with which we can refine that theoretical model and eventually understand the nature of black matter and black energy.

• How did the discovery of the first exoplanet affect the research being done at EPFL?

First there’s the question of scientific knowledge, since this and subsequent discoveries – more than 4,000 other exoplanets have been identified so far – have given us insight into how planetary systems form and enable us to prove, or improve, the underlying models in terms of the physical, chemical and accretive processes. Next, in order to locate more exoplanets as well as smaller ones (similar in size to earth), we need increasingly precise technologies. Enormous progress has been made in this respect over the past 25 years, with the precision of radial speed measurements improving more than fiftyfold! The work done by a number of EPFL labs contributed to some of these advances.

• Can you cite some examples?

Didier Queloz worked with EPFL laboratories to develop differential delay lines for the PRIMA instrument used in the Very Large Telescope Interferometer in Chile. More recently, the Laboratory of Photonics and Quantum Measurements teamed up with the Geneva Observatory to develop highly sophisticated calibration mechanisms for the new very-high-resolution spectrographs used to detect exoplanets that are similar to earth. And the CHEOPS mission run by the University of Bern and the University of Geneva drew on the expertise of EPFL’s Space Center to design the CHEOPS satellite. Once launched on 17 December 2019, it will be used to identify and characterize more exoplanets.

• Did these discoveries influence your career or your job choices?

The focus of my research owes in large part to James Peebles. His book “Principles of Physical Cosmology” sat on my nightstand while I was writing my thesis. Since then, during my career, I was lucky enough to work and interact with Didier Queloz and Michel Mayor – two highly eminent researchers!

Video of Michel Mayor receiving the title of doctor honoris causa at EPFL’s 2002 Master’s degree graduation ceremony (starting at minute 38): https://mediaspace.epfl.ch/media/0_9tusebfu