Cosmic magnetic fields

le 8 octobre 2021, 11h à 13h, Katia Ferrière, salle Coriolis, OMP

Magnetic fields are ubiquitous in the Universe. Most celestial bodies, from planets to stars to galaxies, appear to be magnetized. Even intergalactic space could be threaded by a magnetic field.

Cosmic magnetic fields generally play an important role. They affect the structure of stars and galaxies, govern their internal turbulence, control star formation inside galaxies… They are also responsible for spectacular phenomena, such as polar aurorae, solar flares, galactic jets…

I will start by describing the observational properties of magnetic fields of planets, stars and galaxies. I will then discuss the thorny question of their origin.

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