Active Galactic Nuclei (AGN) are not longer considered part of a small and exotic source population but are now widely accepted to play a significant role in the evolution of galaxies through cosmic time. However, even 20 years after the realization of the close link between the galaxies and the active SMBH that they host, the various mechanisms and the interconnection are not fully clear.
Two complementary approaches are followed to deepen our understanding; detailed studies of individual nearby AGN provide insight into the physics that trigger AGN activity and link it to the spatially resolved host properties, while the large samples of AGN collected from surveys, access the population properties and their impact on the evolution of their hosts with redshift and environment.
Launched successfully in July 2019 on board of the Russian-German SRG mission, the eROSITA instrument and its 7 eyes have started to map the entire sky in X-rays and will continue to do so until the end of 2023. After a short description of eROSITA and its first scientific highlights, I will focus on how eROSITA is contributing to the understanding of AGN using both approaches and what this has to do with my work.
