The Complexity of the Milky Way's Cosmic Bubbles

The giant bubbles of hot gas blown out from the center of the Milky Way galaxy, known as eRosita bubbles, are far more complex than previously believed, according to a new study. The study examined the thermal and chemical properties of these features, revealing hitherto undiscovered properties in their shells. Scientists had previously assumed that galactic bubbles are heated by shocks of gas pushed out from the Milky Way, but the temperature of the gas within the bubbles is similar to the temperature of the gas outside them. The eRosita bubbles are bright not because of their temperature but instead because they are filled with extremely dense gas.