Present and past activity at the Milky Way center

The Milky Way is often considered the prototypical quiescent galaxy. Indeed, Sgr A*, the supermassive black hole sitting at its center, currently accretes at a very small rate of the order of 10^-8-10^-9 the Eddington limit. Concurrently, the Milky Way center is forming stars at a low rate. Nevertheless, recent results reveal that, in the past, the Milky Way center experienced very active phases. I will review the traces of the past activity in the Milky Way center and discuss the potential of eROSITA to measure the hot interstellar and circumgalactic medium.