Organized, large-scale magnetic fields are ubiquitous in the Universe. They originate from a hydromagnetic dynamo process, that is through the motions of conducting fluids in rotating systems. In this seminar, I will discuss the dynamos of the objects which I have encountered so far in my scientific career; namely that of the Sun and Earth-like exoplanets, with the Earth as a prototype for the latter. I will do so in a unified presentation allowing the similarities and differences to be showcased in parallel. An overview of the observations will first be given, followed by a brief outline of dynamo theory. Finally, the most important results of my doctoral thesis regarding the operation of the solar dynamo will be presented, followed by an introduction to my current work on inferring the possible existence of magnetic fields from the structures of rocky exoplanets, themselves deduced from measurements of mass and radii.
Local contact: Thierry FOGLIZZO
Organizer: Frédéric GALLIANO
DAp