La conférence publique Helen Sawyer Hogg

La conférence Helen Sawyer Hogg a été créée en 1985 par la Société canadienne d’astronomie avec la participation de la Société royale d’astronomie du Canada (SRAC), l’Association des planétariums du Canada et l’Institut royal canadien. Depuis, cette conférence publique, supportée conjointement par le fonds de la CASCA et par la SRAC, se tient annuellement au congrès de l’une ou de l’autre des sociétés, en alternance. Elle se veut une reconnaissance des contributions soutenues et diverses de Helen Sawyer Hogg à la prise de conscience du public de l’Univers qui nous entoure. Le choix du conférencier est arrêté par un comité composé des présidents de la CASCA et de la SRAC, ainsi que du président du comité organisateur local, hôte de la rencontre (la CASCA ou la SRAC).

La conférence Helen Sawyer Hogg 2019

Sera Markoff, University of Amsterdam.

Black holes are one of the most exotic consequences of Einstein’s General Relativity, yet they are also very common, from stellar remnants up to beasts over a billion times more massive than our sun. Contrary to their reputation as cosmic vacuum cleaners, they actually serve as engines for extremely energetic processes, converting a large fraction of the ‘fuel’ they capture into other forms that can majorly impact their surroundings. For instance, some black holes launch enormous jets of relativistic plasma, bigger than their host galaxies, that accelerate particles to energies millions of times higher than the Large Hadron Collider at CERN! Astronomers, astrophysicists and physicists all want to understand black holes, yet we have been limited by the resolution of our telescopes from actually seeing one directly. This situation has changed dramatically with the Event Horizon Telescope, an Earth-sized millimeter-wavelength array that revealed to the world what a black hole actually looks like just this past April. I will put this exciting result into context by explaining more about how black holes become such efficient, gravity-powered engines, and why they are important players for many different fields of study. Along the way I will also discuss the areas where we still have major questions, and thus the challenges for the coming years.